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atom.xml
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atom.xml
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<?xml version="1.0" encoding="utf-8"?>
<feed xmlns="http://www.w3.org/2005/Atom">
<title><![CDATA[Greg Eng]]></title>
<link href="http://gregeng.github.io/atom.xml" rel="self"/>
<link href="http://gregeng.github.io/"/>
<updated>2014-08-17T20:21:54-07:00</updated>
<id>http://gregeng.github.io/</id>
<author>
<name><![CDATA[Greg Eng]]></name>
<email><![CDATA[greg.eng@gmail.com]]></email>
</author>
<generator uri="http://octopress.org/">Octopress</generator>
<entry>
<title type="html"><![CDATA[Make Your Website More Accessible With These 5 Tips]]></title>
<link href="http://gregeng.github.io/blog/2014/08/17/make-your-website-more-accessible-with-these-5-tips/"/>
<updated>2014-08-17T19:59:00-07:00</updated>
<id>http://gregeng.github.io/blog/2014/08/17/make-your-website-more-accessible-with-these-5-tips</id>
<content type="html"><![CDATA[<p>Optimizing a website to adhere to web accessibility standards allows for a wider audience and user base. An accessible website should allow users who use screen readers and/or depend fully on the keyboard to use every piece of functionality on the website, in a logical manner.</p>
<p>In a recent project for work, I was tasked with creating a web accessible media display that passed AA standards. The following information and tips are things I wish I had a few weeks ago in order to help with the process. I hope it helps someone else in the future!</p>
<h1>Essentials:</h1>
<ul>
<li>Make sure everything is accessible by tab / shift+tab.</li>
<li>Err on the side of semantic html rather than forcing the use of the global tab index attribute. (In some cases, it will be unavoidable … like in certain description overlays or media lightboxes)</li>
<li>Provide a <code>title</code> to all <code><a></code> tags so that screen readers can read it.</li>
<li>Provide <code>alt</code> text to all images.</li>
<li>Use text as often as possible so that screen readers will successfully be able to provide voice over to the content. If it is not possible to use text due to specific styling concerns, make sure to be diligent about the alternate text that is associated with the image.</li>
<li>Choose colors with a high amount of contrast to make text easily readable.</li>
</ul>
<h1>5 Pro-Tips:</h1>
<ol>
1. Set up an event listener to add a class to the body of using-keyboard.
<p>This allows you to implement different :focus pseudo-class selectors when using/not using the keyboard.</p>
<figure class='code'><figcaption><span></span></figcaption><div class="highlight"><table><tr><td class="gutter"><pre class="line-numbers"><span class='line-number'>1</span>
<span class='line-number'>2</span>
<span class='line-number'>3</span>
<span class='line-number'>4</span>
<span class='line-number'>5</span>
<span class='line-number'>6</span>
<span class='line-number'>7</span>
</pre></td><td class='code'><pre><code class='js'><span class='line'><span class="nx">$</span><span class="p">(</span><span class="nb">document</span><span class="p">).</span><span class="nx">keydown</span><span class="p">(</span><span class="kd">function</span><span class="p">(</span><span class="nx">e</span><span class="p">)</span> <span class="p">{</span>
</span><span class='line'> <span class="nx">$</span><span class="p">(</span><span class="s1">'body'</span><span class="p">).</span><span class="nx">addClass</span><span class="p">(</span><span class="s1">'using-keyboard'</span><span class="p">);</span>
</span><span class='line'><span class="p">});</span>
</span><span class='line'>
</span><span class='line'><span class="nx">$</span><span class="p">(</span><span class="nb">document</span><span class="p">).</span><span class="nx">mouseup</span><span class="p">(</span><span class="kd">function</span><span class="p">(</span><span class="nx">e</span><span class="p">)</span> <span class="p">{</span>
</span><span class='line'> <span class="nx">$</span><span class="p">(</span><span class="s1">'body'</span><span class="p">).</span><span class="nx">removeClass</span><span class="p">(</span><span class="s1">'using-keyboard'</span><span class="p">);</span>
</span><span class='line'><span class="p">});</span>
</span></code></pre></td></tr></table></div></figure>
2. Write :focus and :active styles.
<figure class='code'><figcaption><span></span></figcaption><div class="highlight"><table><tr><td class="gutter"><pre class="line-numbers"><span class='line-number'>1</span>
<span class='line-number'>2</span>
<span class='line-number'>3</span>
<span class='line-number'>4</span>
<span class='line-number'>5</span>
<span class='line-number'>6</span>
<span class='line-number'>7</span>
<span class='line-number'>8</span>
<span class='line-number'>9</span>
<span class='line-number'>10</span>
<span class='line-number'>11</span>
</pre></td><td class='code'><pre><code class='css'><span class='line'><span class="o">*</span> <span class="nt">body</span><span class="nc">.using-keyboard</span><span class="nd">:focus</span> <span class="p">{</span>
</span><span class='line'> <span class="k">outline</span><span class="o">:</span> <span class="m">2px</span> <span class="k">dashed</span> <span class="nb">red</span><span class="p">;</span>
</span><span class='line'><span class="p">}</span>
</span><span class='line'>
</span><span class='line'><span class="o">*</span><span class="nd">:focus</span> <span class="p">{</span>
</span><span class='line'> <span class="k">outline</span><span class="o">:</span> <span class="m">2px</span> <span class="k">dashed</span> <span class="nb">red</span><span class="p">;</span>
</span><span class='line'><span class="p">}</span>
</span><span class='line'>
</span><span class='line'><span class="o">*</span><span class="nd">:active</span> <span class="p">{</span>
</span><span class='line'> <span class="k">outline</span><span class="o">:</span> <span class="k">none</span><span class="p">;</span>
</span><span class='line'><span class="p">}</span>
</span></code></pre></td></tr></table></div></figure>
3. Use this function to make things behind an overlay inaccessible via keyboard.
<figure class='code'><figcaption><span></span></figcaption><div class="highlight"><table><tr><td class="gutter"><pre class="line-numbers"><span class='line-number'>1</span>
<span class='line-number'>2</span>
<span class='line-number'>3</span>
</pre></td><td class='code'><pre><code class='js'><span class='line'><span class="nx">$</span><span class="p">(</span><span class="s1">'.the-last-element-you-want-to-tab'</span><span class="p">).</span><span class="nx">blur</span><span class="p">(</span><span class="kd">function</span><span class="p">(){</span>
</span><span class='line'> <span class="nx">$</span><span class="p">(</span><span class="s1">'.the-first-element-you-want-to-tab'</span><span class="p">).</span><span class="nx">focus</span><span class="p">();</span>
</span><span class='line'><span class="p">});</span>
</span></code></pre></td></tr></table></div></figure>
<p>Thank you to <a href="http://stackoverflow.com/questions/11351983/how-to-limit-tab-indexes-to-just-an-overlay-and-its-elements
" target="_blank">this post</a> on stackoverflow for helping me solve this issue.</p>
4. Force a specific tabindex keyboard interaction flow
<p>If tab indexes aren’t working properly… which can be highly likely in Internet Explorer, you can force the route you want the user flow to go with this function. Note you will need to be very specific about the global tab index property.</p>
<figure class='code'><figcaption><span></span></figcaption><div class="highlight"><table><tr><td class="gutter"><pre class="line-numbers"><span class='line-number'>1</span>
<span class='line-number'>2</span>
<span class='line-number'>3</span>
<span class='line-number'>4</span>
<span class='line-number'>5</span>
<span class='line-number'>6</span>
<span class='line-number'>7</span>
<span class='line-number'>8</span>
<span class='line-number'>9</span>
<span class='line-number'>10</span>
<span class='line-number'>11</span>
</pre></td><td class='code'><pre><code class='js'><span class='line'><span class="kd">var</span> <span class="nx">tabindex</span> <span class="o">=</span> <span class="nx">$</span><span class="p">(</span><span class="s1">'*:focus'</span><span class="p">).</span><span class="nx">attr</span><span class="p">(</span><span class="s1">'tabindex'</span><span class="p">);</span>
</span><span class='line'><span class="kd">var</span> <span class="nx">lastTabindex</span> <span class="o">=</span> <span class="mi">10</span><span class="p">;</span> <span class="c1">// make this the highest tab index number you have on the page</span>
</span><span class='line'><span class="nx">$</span><span class="p">(</span><span class="nb">document</span><span class="p">).</span><span class="nx">keyup</span><span class="p">(</span><span class="kd">function</span><span class="p">(</span><span class="nx">e</span><span class="p">)</span> <span class="p">{</span>
</span><span class='line'> <span class="k">if</span> <span class="p">(</span><span class="nx">e</span><span class="p">.</span><span class="nx">which</span> <span class="o">===</span> <span class="mi">9</span> <span class="o">&&</span> <span class="nx">tabindex</span> <span class="o">!==</span> <span class="nx">lastTabindex</span><span class="p">)</span> <span class="p">{</span>
</span><span class='line'> <span class="nx">tabindex</span> <span class="o">+=</span> <span class="mi">1</span><span class="p">;</span>
</span><span class='line'> <span class="nx">$</span><span class="p">(</span><span class="s1">'[tabindex='</span> <span class="o">+</span> <span class="nx">tabindex</span> <span class="o">+</span> <span class="s1">']'</span><span class="p">).</span><span class="nx">focus</span><span class="p">();</span>
</span><span class='line'> <span class="p">}</span> <span class="k">else</span> <span class="p">{</span>
</span><span class='line'> <span class="nx">tabindex</span> <span class="o">=</span> <span class="mi">1</span><span class="p">;</span>
</span><span class='line'> <span class="nx">$</span><span class="p">(</span><span class="s1">'[tabindex=1]'</span><span class="p">).</span><span class="nx">focus</span><span class="p">();</span>
</span><span class='line'> <span class="p">}</span>
</span><span class='line'><span class="p">});</span>
</span></code></pre></td></tr></table></div></figure>
5. Reset focus to triggering elements.
This is applicable after visiting another page, overlay, lightbox, etc.<br>
<p>An easy way to do this is to assign an id to the tag that triggers the page, overlay, or lightbox. After closing that region, reset focus to the triggering element with jQuery by focusing on the asset matching the id.</p>
</ol>
<h3>Additional Resources:</h3>
<ul>
<li><a href="http://www.w3.org/WAI/intro/accessibility.php">http://www.w3.org/WAI/intro/accessibility.php</a></li>
<li><a href="http://www.w3.org/WAI/WCAG20/quickref/Overview.php">http://www.w3.org/WAI/WCAG20/quickref/Overview.php</a></li>
<li><a href="http://www.w3.org/TR/WCAG20/">http://www.w3.org/TR/WCAG20/</a></li>
</ul>
<p>And if you were curious to interact with the final product, web accessible and all … you can check it out at:</p>
<p><a href="http://firstdayofschool.target.com" target="_blank">firstdayofschool.target.com</a></p>
]]></content>
</entry>
<entry>
<title type="html"><![CDATA[Environment Setup for Calabash Testing]]></title>
<link href="http://gregeng.github.io/blog/2014/03/10/environment-setup-for-calabash-testing/"/>
<updated>2014-03-10T21:25:00-07:00</updated>
<id>http://gregeng.github.io/blog/2014/03/10/environment-setup-for-calabash-testing</id>
<content type="html"><![CDATA[<p>In order to begin writing automated test suites with <a href="http://calaba.sh/" target="_blank">calabash</a>, you will need to set up your dev environment.</p>
<p>This is an exciting and necessary step in achieving a productive scripting work flow. So I thought I would write this guide to lower the barrier to entry and help you get up and running sooner.</p>
<p>Both <code>calabash-ios</code> and <code>calabash-android</code> were originially written as Ruby libraries. Therefore, I will be showing you how to set it up using Ruby and Mac OSX.</p>
<p>Let’s get started:<br></p>
<ol>
<li>Install <a href="http://brew.sh/" target="_blank">Homebrew</a> (The missing package manager for OS X)<br><br>
<ul>
<li>From the shell run:<br><br>
<ul>
<li><code>ruby -e "$(curl -fsSL https://raw.github.com/Homebrew/homebrew/go/install)"</code><br><br></li>
</ul>
</li>
</ul>
</li>
<li>Install <a href="https://rvm.io/" target="_blank">RVM</a> (Ruby Version Manager)<br><br>
<ul>
<li>Currently, I am using the following version: <code>ruby 2.0.0p247</code><br><br></li>
<li>In order to replicate my environment, run this from the shell:<br><br>
<ul>
<li><code>rvm install 2.0.0-p247</code></li>
<li><code>rvm --default use 2.0.0-p247</code><br><br></li>
</ul>
</li>
</ul>
</li>
<li>Install <a href="https://developer.apple.com/xcode/" target="_blank">Xcode</a>, the Command Line Tools, and iOS Simulators<br><br>
<ul>
<li>Open up the Mac App Store and search for Xcode.<br><br></li>
<li>Install Xcode from there and login using your Apple Developer login/password.<br><br></li>
<li>Once the application is installed, open it up and download the Command Line Tools and iOS Simulators.<br><br>
<ul>
<li>They should be located within Xcode Preferences –> Downloads<br><br>
<ul>
<li>If for some reason they are not available there, search for them <a href="https://daw.apple.com/cgi-bin/WebObjects/DSAuthWeb.woa/wa/login?&appIdKey=891bd3417a7776362562d2197f89480a8547b108fd934911bcbea0110d07f757&path=%2F%2Fdownloads%2Findex.action#" target="_blank">here</a>.<br><br></li>
</ul>
</li>
</ul>
</li>
</ul>
</li>
<li>Install Required <a href="http://rubygems.org/" target="_blank">Gems</a> (The Ruby Package Management System)<br><br>
<ul>
<li>From the shell run:<br><br>
<ul>
<li><code>gem install 'bundler'</code></li>
<li><code>gem install 'calabash-cucumber'</code></li>
<li><code>gem install 'calabash-android'</code></li>
<li><code>gem install 'pry'</code><br><br></li>
</ul>
</li>
</ul>
</li>
<li><p>Install the <a href="http://developer.android.com/tools/help/adb.html" target="_blank">Android Debug Bridge</a> (adb)<br></p>
<ul>
<li>Download the Android <a href="http://developer.android.com/sdk/index.html" target="_blank">SDK</a><br><br></li>
<li>Unzip the file and rename the folder to “ <em>android-sdk</em> ”<br><br></li>
<li>Nest the folder in any directory you like. I suggest <code>/Users/YOURUSERNAME/Development</code><br><br></li>
<li>Add the folder location to your <code>$PATH</code><br><br>
<ul>
<li>From the shell: <code>cd</code> then <code>open -a TextEdit .bash_profile</code><br><br></li>
<li>Add this: <code>export PATH="/Users/YOURUSERNAME/Development/android-sdk/platform-tools/":$PATH</code><br><br></li>
</ul>
</li>
<li>Open a new shell window and enter the command <code>adb</code><br><br></li>
<li>If you see a list of adb help commands, you’re all set!<br><br></li>
</ul>
</li>
<li><p>Generate an Android <a href="https://github.com/calabash/calabash-android/wiki/Running-Calabash-Android" target="_blank">debug.keystore</a><br><br></p>
<ul>
<li>If debug.keystore is missing, it be recreated in <code>ANDROID_HOME</code> with the following command:<br><br>
<code>
keytool -genkey -v -keystore ~/.android/debug.keystore -alias androiddebugkey -storepass android -keypass android -keyalg RSA -keysize 2048 -validity 10000 -dname "CN=Android Debug,O=Android,C=US"
</code><br><br></li>
</ul>
</li>
<li>Download <a href="https://cloud.genymotion.com/page/launchpad/download/" target="_blank">Genymotion</a><br><br>
<ul>
<li>This is an alternative Android emulator.<br><br></li>
</ul>
</li>
<li>Download Oracle <a href="https://www.virtualbox.org/wiki/Downloads" target="_blank">VirtualBox</a><br><br>
<ul>
<li>This works in conjunction with Genymotion to simulate Android devices.<br><br></li>
</ul>
</li>
<li>Enable the Google Playstore on <strong>all</strong> your virtual device simulators<br><br>
<ul>
<li>If you are not signed in with an account on the Google Playstore on each device, you will not be able to run calabash automated scripts in the simulator.<br><br></li>
<li>Here is an excellent <a href="http://stackoverflow.com/questions/17831990/how-do-you-install-google-frameworks-play-accounts-etc-on-a-genymotion-virtu" target="_blank">guide</a> from Stack Overflow detailing how to do this.<br><br></li>
<li>I consistently use the Galaxy Nexus 4.3 API 18 when authoring scripts locally. Of course, feel free to choose any device or version level you want.<br><br></li>
</ul>
</li>
</ol>
<p>…and that’s it!<br>
Assuming everything went well, you are now ready to begin writing calabash powered, automated test suites. Enjoy!</p>
]]></content>
</entry>
<entry>
<title type="html"><![CDATA[Hello Again]]></title>
<link href="http://gregeng.github.io/blog/2014/03/09/hello-again/"/>
<updated>2014-03-09T20:46:00-07:00</updated>
<id>http://gregeng.github.io/blog/2014/03/09/hello-again</id>
<content type="html"><![CDATA[<p>It’s been a few months since I’ve updated my blog and I apologize! But a lot has happened since then. I graduated from the <a href="http://flatironschool.com/" target="_blank">Flatiron School</a>, moved from New York to San Francisco, and started a new job.</p>
<p>For the past 2 months, I’ve been working at <a href="http://xamarin.com/" target="_blank">Xamarin</a> as a Mobile Test Automation <a href="http://xamarin.com/jobs/ofc4Xfwc" target="_blank">Intern</a>.</p>
<p>This means I get to author <em>automated</em> UI test scripts for various Android and iOS applications. These scripts then aid in ensuring the highest quality apps by testing them for functional bugs and UI mishaps across various devices in a burgeoning product called the Xamarin <a href="http://xamarin.com/test-cloud" target="_blank">Test Cloud</a>.</p>
<p>In a previous role, I was <em>manually</em> QA testing mobile applications on both platforms, so in a way …things have come full circle. It’s really exciting to apply new skills to a familiar craft.</p>
<p>In the past 8 weeks I have learned so much and I anticipate learning even more. I want to seize the opportunity to write about it. I’m looking forward to covering topics such as testing, QA, BDD, mobile, <a href="http://cukes.info/" target="_blank">cucumber</a>, and <a href="http://calaba.sh/" target="_blank">calabash</a>.</p>
<p>I’m excited to tell you all about it.<br><br>Until then!</p>
]]></content>
</entry>
<entry>
<title type="html"><![CDATA[Hide Your Keys, Hide Your Tokens ... Unless Deploying to Heroku]]></title>
<link href="http://gregeng.github.io/blog/2013/11/21/hide-your-keys/"/>
<updated>2013-11-21T09:33:00-08:00</updated>
<id>http://gregeng.github.io/blog/2013/11/21/hide-your-keys</id>
<content type="html"><![CDATA[<p>In that case, you have to do a little more than just hide them.</p>
<p>Typically, an API will require a key or authentication token before serving data downstream. It’s logical to avoid committing any of these to a public repo on GitHub, so I often found myself falling into a pattern. I would make hidden files in the assets folder of my project, then <code>.gitignore</code> each one.</p>
<p>It would result in a folder structure that might look like this:</p>
<figure class='code'><figcaption><span></span></figcaption><div class="highlight"><table><tr><td class="gutter"><pre class="line-numbers"><span class='line-number'>1</span>
<span class='line-number'>2</span>
<span class='line-number'>3</span>
<span class='line-number'>4</span>
<span class='line-number'>5</span>
<span class='line-number'>6</span>
</pre></td><td class='code'><pre><code class='bash'><span class='line'>/project
</span><span class='line'> /lib
</span><span class='line'> /assets
</span><span class='line'> .api_key
</span><span class='line'> .auth_token
</span><span class='line'> .password
</span></code></pre></td></tr></table></div></figure>
<p>Then in the class that controls all of the API calls, I would do something like this:</p>
<figure class='code'><figcaption><span></span></figcaption><div class="highlight"><table><tr><td class="gutter"><pre class="line-numbers"><span class='line-number'>1</span>
<span class='line-number'>2</span>
<span class='line-number'>3</span>
<span class='line-number'>4</span>
<span class='line-number'>5</span>
<span class='line-number'>6</span>
<span class='line-number'>7</span>
<span class='line-number'>8</span>
<span class='line-number'>9</span>
<span class='line-number'>10</span>
<span class='line-number'>11</span>
<span class='line-number'>12</span>
<span class='line-number'>13</span>
</pre></td><td class='code'><pre><code class='ruby'><span class='line'><span class="no">Class</span> <span class="no">API</span>
</span><span class='line'>
</span><span class='line'> <span class="no">API_KEY</span> <span class="o">=</span> <span class="nb">open</span><span class="p">(</span><span class="s1">'lib/assets/.api_key'</span><span class="p">)</span><span class="o">.</span><span class="n">read</span><span class="p">()</span>
</span><span class='line'> <span class="no">AUTH_TOKEN</span> <span class="o">=</span> <span class="nb">open</span><span class="p">(</span><span class="s1">'lib/assets/.auth_token'</span><span class="p">)</span><span class="o">.</span><span class="n">read</span>
</span><span class='line'> <span class="no">PASSWORD</span> <span class="o">=</span> <span class="nb">open</span><span class="p">(</span><span class="s1">'lib/assets/.password'</span><span class="p">)</span><span class="o">.</span><span class="n">read</span>
</span><span class='line'>
</span><span class='line'> <span class="k">def</span> <span class="nf">some_method</span>
</span><span class='line'> <span class="ss">:user_key</span> <span class="o">=></span> <span class="no">API_KEY</span>
</span><span class='line'> <span class="ss">:user_token</span> <span class="o">=></span> <span class="no">AUTH_TOKEN</span>
</span><span class='line'> <span class="ss">:user_password</span> <span class="o">=></span> <span class="no">PASSWORD</span>
</span><span class='line'> <span class="k">end</span>
</span><span class='line'>
</span><span class='line'><span class="k">end</span>
</span></code></pre></td></tr></table></div></figure>
<p>I set each relevant piece to a constant to be used in methods throughout the API interactions.</p>
<p>This way feels a little clunky, but it works. As long as you remember to add each hidden file to the .gitignore, it keeps the credentials safe. But as a project grows and it accumulates more authorizations, it becomes a little difficult to manage.</p>
<p>It wasn’t until my group tried to deploy an app to Heroku that we discovered the better way. Heroku makes it simple to deploy a Rails app, but as a result it lacks a lot of the bells and whistles. As a result, it is impossible to log in to the server in a shell to upload each individual hidden file described above.</p>
<p>In order to accomplish the same level of security and function, we can instead use Heroku config variables that will be read at runtime. Heroku has some great <a href="https://devcenter.heroku.com/articles/config-vars#local-setup" target="_blank">documentation</a> on this topic.</p>
<p>It’s very easy to set up from the local shell. Thanks to my teammate <a href="http://davidbella.github.io/" target="_blank">David Bella</a>, we were able to figure out what we needed to do immediately.</p>
<p>Just navigate to the root of your project directory and run the <code>heroku config:set</code> command.</p>
<p>For example:</p>
<figure class='code'><figcaption><span></span></figcaption><div class="highlight"><table><tr><td class="gutter"><pre class="line-numbers"><span class='line-number'>1</span>
<span class='line-number'>2</span>
<span class='line-number'>3</span>
</pre></td><td class='code'><pre><code class='bash'><span class='line'>heroku config:set <span class="nv">API_KEY</span><span class="o">=</span>abcefghijklmnopqrstuvwxyz
</span><span class='line'>heroku config:set <span class="nv">AUTH_TOKEN</span><span class="o">=</span>abc123doremi
</span><span class='line'>heroku config:set <span class="nv">PASSWORD</span><span class="o">=</span>p4ssw0rd
</span></code></pre></td></tr></table></div></figure>
<p>That’s all there is to it! If you want to see your setup at any point, just type <code>heroku config</code> to see an output like this:</p>
<figure class='code'><figcaption><span></span></figcaption><div class="highlight"><table><tr><td class="gutter"><pre class="line-numbers"><span class='line-number'>1</span>
<span class='line-number'>2</span>
<span class='line-number'>3</span>
</pre></td><td class='code'><pre><code class='bash'><span class='line'>API_KEY: abcefghijklmnopqrstuvwxyz
</span><span class='line'>AUTH_TOKEN: abc123doremi
</span><span class='line'>PASSWORD: p4ssw0rd
</span></code></pre></td></tr></table></div></figure>
<p>This is great for production, but how can we get the same level of organization and clarity for our development environment? My classmate <a href="http://scottluptowski.com/" target="_blank">Scott Luptowski</a> told us about the <a href="https://github.com/bkeepers/dotenv" target="_blank">dotenv</a> gem that assists with that exact problem.</p>
<p>Start by including <code>gem 'dotenv-rails'</code> in your <code>Gemfile</code> in the appropriate groups. We only use it in <code>:test</code> and <code>:development</code>. Then, make a <code>.env</code> file at the root of your project directory. In it, include the assignments for each of the keys, tokens or passwords you want to call.</p>
<p>For example:</p>
<figure class='code'><figcaption><span></span></figcaption><div class="highlight"><table><tr><td class="gutter"><pre class="line-numbers"><span class='line-number'>1</span>
<span class='line-number'>2</span>
<span class='line-number'>3</span>
</pre></td><td class='code'><pre><code class='bash'><span class='line'><span class="nv">API_KEY</span><span class="o">=</span>abcefghijklmnopqrstuvwxyz
</span><span class='line'><span class="nv">AUTH_TOKEN</span><span class="o">=</span>abc123doremi
</span><span class='line'><span class="nv">PASSWORD</span><span class="o">=</span>p4ssw0rd
</span></code></pre></td></tr></table></div></figure>
<p>Rails will be able to call these variables anywhere in the application by using this pattern: <code>ENV['API_KEY']</code>, <code>ENV['AUTH_TOKEN']</code>, <code>ENV['PASSWORD']</code>. The hard coded keys will stay out of your code and you will have one organized place to manage all the necessary information. Just remember to also add the .env file to your .gitignore. The app should now work seamlessly in both local development and production Heroku environments. A simple solution for an important problem!</p>
]]></content>
</entry>
<entry>
<title type="html"><![CDATA[I Like My Coffee Strong ... and My Params Stronger]]></title>
<link href="http://gregeng.github.io/blog/2013/11/06/i-like-my-coffee-strong-and-my-params-stronger/"/>
<updated>2013-11-06T21:16:00-08:00</updated>
<id>http://gregeng.github.io/blog/2013/11/06/i-like-my-coffee-strong-and-my-params-stronger</id>
<content type="html"><![CDATA[<p>Before understanding the need for strong params in Rails, let’s take a look at the idea of mass assignment in Ruby.</p>
<p>Mass assignment is a convenient technique rubyists can use to easily assign multiple attributes to an object at instantiation. Yanik Jayaram provides an excellent description of it in his blog <a href="http://modernlegend.github.io/blog/2013/03/16/what-is-mass-assignment/" target="_blank">post</a>. It uses elements of metaprogramming and the idea of dynamic definition which is artfully described by Emily Xie <a href="http://emilyxxie.github.io/blog/2013/11/02/defining-the-undefined-dynamic-definition-for-ruby-newcomers/" target="_blank">here</a>.</p>
<p>This pattern becomes extremely useful in Rails when dealing with user input in forms. A sign up form is a great place for this pattern.</p>
<p>Let’s take a look at an example:</p>
<div align="center">
<h2>Sign Up</h2>
<form accept-charset="UTF-8" action="/create" class="signup-form" id="user_new" method="post">
<input type="text" name="user[first_name]" placeholder="First name" value=""><br>
<input type="text" name="user[last_name]" placeholder="Last name" value=""><br>
<input type="email" name="user[email]" placeholder="Email Address" value=""><br>
<input type="password" name="user[password]" placeholder="Password"><br>
<input type="password" name="user[password_confirmation]" placeholder="Confirm Password"><br>
</form>
</div>
<p>And here is the markup used to create that form:</p>
<figure class='code'><figcaption><span></span></figcaption><div class="highlight"><table><tr><td class="gutter"><pre class="line-numbers"><span class='line-number'>1</span>
<span class='line-number'>2</span>
<span class='line-number'>3</span>
<span class='line-number'>4</span>
<span class='line-number'>5</span>
<span class='line-number'>6</span>
<span class='line-number'>7</span>
</pre></td><td class='code'><pre><code class='html'><span class='line'><span class="nt"><form</span> <span class="na">action=</span><span class="s">"/create"</span> <span class="na">method=</span><span class="s">"post"</span><span class="nt">></span>
</span><span class='line'> <span class="nt"><input</span> <span class="na">type=</span><span class="s">"text"</span> <span class="na">name=</span><span class="s">"user[first_name]"</span> <span class="na">placeholder=</span><span class="s">"First name"</span> <span class="na">value=</span><span class="s">""</span><span class="nt">></span>
</span><span class='line'> <span class="nt"><input</span> <span class="na">type=</span><span class="s">"text"</span> <span class="na">name=</span><span class="s">"user[last_name]"</span> <span class="na">placeholder=</span><span class="s">"Last name"</span> <span class="na">value=</span><span class="s">""</span><span class="nt">></span>
</span><span class='line'> <span class="nt"><input</span> <span class="na">type=</span><span class="s">"email"</span> <span class="na">name=</span><span class="s">"user[email]"</span> <span class="na">placeholder=</span><span class="s">"Email Address"</span> <span class="na">value=</span><span class="s">""</span><span class="nt">></span>
</span><span class='line'> <span class="nt"><input</span> <span class="na">type=</span><span class="s">"password"</span> <span class="na">name=</span><span class="s">"user[password]"</span> <span class="na">placeholder=</span><span class="s">"Password"</span> <span class="nt">></span>
</span><span class='line'> <span class="nt"><input</span> <span class="na">type=</span><span class="s">"password"</span> <span class="na">name=</span><span class="s">"user[password_confirmation]"</span> <span class="na">placeholder=</span><span class="s">"Confirm Password"</span> <span class="nt">></span>
</span><span class='line'><span class="nt"></form></span>
</span></code></pre></td></tr></table></div></figure>
<p>Once the user submits this form, the params hash will inlude all the input values neatly nested as key value pairs within the sub key <code>user</code> hash. Then, it would be appropriate to assume somewhere in the <code>UsersController</code>, there is a method like this:</p>
<figure class='code'><figcaption><span></span></figcaption><div class="highlight"><table><tr><td class="gutter"><pre class="line-numbers"><span class='line-number'>1</span>
<span class='line-number'>2</span>
<span class='line-number'>3</span>
<span class='line-number'>4</span>
<span class='line-number'>5</span>
<span class='line-number'>6</span>
<span class='line-number'>7</span>
<span class='line-number'>8</span>
<span class='line-number'>9</span>
<span class='line-number'>10</span>
<span class='line-number'>11</span>
</pre></td><td class='code'><pre><code class='ruby'><span class='line'><span class="no">UsersController</span>
</span><span class='line'>
</span><span class='line'> <span class="k">def</span> <span class="nf">create</span>
</span><span class='line'> <span class="vi">@user</span> <span class="o">=</span> <span class="no">User</span><span class="o">.</span><span class="n">new</span><span class="p">(</span><span class="n">params</span><span class="o">[</span><span class="ss">:user</span><span class="o">]</span><span class="p">)</span>
</span><span class='line'> <span class="k">if</span> <span class="vi">@user</span><span class="o">.</span><span class="n">save</span>
</span><span class='line'> <span class="n">redirect_to</span> <span class="vi">@user</span>
</span><span class='line'> <span class="k">else</span>
</span><span class='line'> <span class="s2">"Error!"</span>
</span><span class='line'> <span class="k">end</span>
</span><span class='line'> <span class="k">end</span>
</span><span class='line'><span class="k">end</span>
</span></code></pre></td></tr></table></div></figure>
<p>Instead of having to individually call the following methods, <code>first_name=</code>, <code>last_name=</code>, <code>email=</code>, and <code>password=</code> to set all of these input values … mass assignment lets us get it done at a higher level of abstraction.</p>
<p>But with this convenience lies a crucial vulnerability. In the form example above, we can assume that this web application is backed by a database with a <code>users</code> table that may have more columns than the form leads us to believe. Perhaps administrators also have user accounts within the application and certain permissions are allocated to them. This could be based on an <code>admin</code> column that takes a boolean value of 0 or 1.</p>
<p>Using this knowledge, we can maliciously change any one of the inputs to alter the <code>admin</code> column instead … even if this wasn’t the original intent of the form. Using Google’s Chrome browser, I can inspect the element of the form and change the email input field to reference <code>user[admin]</code> instead of <code>user[email]</code></p>
<p>That might look something like this:</p>
<div align="center">
<h2>Sign Up</h2>
<form accept-charset="UTF-8" action="/create" class="signup-form" id="user_new" method="post">
<input type="text" name="user[first_name]" placeholder="First name" value="Greg"><br>
<input type="text" name="user[last_name]" placeholder="Last name" value="Eng"><br>
<input type="email" name="user[admin]" placeholder="Email Address" value="1"><br>
<input type="password" name="user[password]" placeholder="Password" value="password"><br>
<input type="password" name="user[password_confirmation]" placeholder="Confirm Password" value="password"><br>
</form>
</div>
<figure class='code'><figcaption><span></span></figcaption><div class="highlight"><table><tr><td class="gutter"><pre class="line-numbers"><span class='line-number'>1</span>
<span class='line-number'>2</span>
<span class='line-number'>3</span>
<span class='line-number'>4</span>
<span class='line-number'>5</span>
<span class='line-number'>6</span>
<span class='line-number'>7</span>
</pre></td><td class='code'><pre><code class='html'><span class='line'><span class="nt"><form</span> <span class="na">action=</span><span class="s">"/create"</span> <span class="na">method=</span><span class="s">"post"</span><span class="nt">></span>
</span><span class='line'> <span class="nt"><input</span> <span class="na">type=</span><span class="s">"text"</span> <span class="na">name=</span><span class="s">"user[first_name]"</span> <span class="na">placeholder=</span><span class="s">"First name"</span> <span class="na">value=</span><span class="s">""</span><span class="nt">></span>
</span><span class='line'> <span class="nt"><input</span> <span class="na">type=</span><span class="s">"text"</span> <span class="na">name=</span><span class="s">"user[last_name]"</span> <span class="na">placeholder=</span><span class="s">"Last name"</span> <span class="na">value=</span><span class="s">""</span><span class="nt">></span>
</span><span class='line'> <span class="nt"><input</span> <span class="na">type=</span><span class="s">"email"</span> <span class="na">name=</span><span class="s">"user[admin]"</span> <span class="na">placeholder=</span><span class="s">"Email Address"</span> <span class="na">value=</span><span class="s">""</span><span class="nt">></span>
</span><span class='line'> <span class="nt"><input</span> <span class="na">type=</span><span class="s">"password"</span> <span class="na">name=</span><span class="s">"user[password]"</span> <span class="na">placeholder=</span><span class="s">"Password"</span> <span class="nt">></span>
</span><span class='line'> <span class="nt"><input</span> <span class="na">type=</span><span class="s">"password"</span> <span class="na">name=</span><span class="s">"user[password_confirmation]"</span> <span class="na">placeholder=</span><span class="s">"Confirm Password"</span> <span class="nt">></span>
</span><span class='line'><span class="nt"></form></span>
</span></code></pre></td></tr></table></div></figure>
<p>Now when I submit this form, the controller is going to create a record in the <code>users</code> table that is missing my email address. Instead, it will set the <code>admin</code> column to true and give me admin access rights to the application. Depending on the domain, I might be able to see and do a multitude of things I normally couldn’t otherwise. That seems not preferable.</p>
<p>Luckily part of the Rails 4.0 core is a pattern that reinforces the idea of strong params. If we were to generate a scaffold using the <code>user</code> resource detailed above, it would produce 2 methods in the controller that look like this:</p>
<figure class='code'><figcaption><span></span></figcaption><div class="highlight"><table><tr><td class="gutter"><pre class="line-numbers"><span class='line-number'>1</span>
<span class='line-number'>2</span>
<span class='line-number'>3</span>
<span class='line-number'>4</span>
<span class='line-number'>5</span>
<span class='line-number'>6</span>
<span class='line-number'>7</span>
<span class='line-number'>8</span>
<span class='line-number'>9</span>
<span class='line-number'>10</span>
<span class='line-number'>11</span>
<span class='line-number'>12</span>
<span class='line-number'>13</span>
<span class='line-number'>14</span>
<span class='line-number'>15</span>
<span class='line-number'>16</span>
<span class='line-number'>17</span>
<span class='line-number'>18</span>
<span class='line-number'>19</span>
</pre></td><td class='code'><pre><code class='ruby'><span class='line'><span class="c1"># Rails 4.0</span>
</span><span class='line'>
</span><span class='line'><span class="no">UsersController</span>
</span><span class='line'>
</span><span class='line'> <span class="k">def</span> <span class="nf">create</span>
</span><span class='line'> <span class="vi">@user</span> <span class="o">=</span> <span class="no">User</span><span class="o">.</span><span class="n">new</span><span class="p">(</span><span class="n">user_params</span><span class="p">)</span>
</span><span class='line'> <span class="k">if</span> <span class="vi">@user</span><span class="o">.</span><span class="n">save</span>
</span><span class='line'> <span class="n">redirect_to</span> <span class="vi">@user</span>
</span><span class='line'> <span class="k">else</span>
</span><span class='line'> <span class="s2">"Error!"</span>
</span><span class='line'> <span class="k">end</span>
</span><span class='line'> <span class="k">end</span>
</span><span class='line'>
</span><span class='line'> <span class="kp">private</span>
</span><span class='line'> <span class="k">def</span> <span class="nf">user_params</span>
</span><span class='line'> <span class="n">params</span><span class="o">.</span><span class="n">require</span><span class="p">(</span><span class="ss">:user</span><span class="p">)</span><span class="o">.</span><span class="n">permit</span><span class="p">(</span><span class="ss">:first_name</span><span class="p">,</span> <span class="ss">:last_name</span><span class="p">,</span> <span class="ss">:email</span><span class="p">,</span> <span class="ss">:password</span><span class="p">)</span>
</span><span class='line'> <span class="k">end</span>
</span><span class='line'> <span class="k">end</span>
</span><span class='line'><span class="k">end</span>
</span></code></pre></td></tr></table></div></figure>
<p>This pattern illustrates the idea of sanitizing the parameters before letting them get anywhere near our domain model. Instead of directly taking in the params submitted through the internet form in the <code>create</code> method, we will first call the <code>private</code> method <code>user_params</code> (named after the resource). This says it should require a sub key of <code>user</code> (resource name) and then only permit certain keys to make it through to the domain model. In effect, this creates a white list of acceptable inputs or <em>strong parameters</em>.</p>
<p>Now, the worst thing that could happen is a form that is submitted with incomplete user data. I think most would agree that is better than the former scenario.</p>
<p>The Rails scaffold comments on this pattern directly in the controller file:</p>
<blockquote><p>Never trust parameters from the scary internet, only allow the white list through.</p></blockquote>
<p>I like to imagine <a href="https://twitter.com/dhh/status/182591044108562433" target="_blank">DHH</a> himself saying this to really drive this point home.</p>
<p>So you too should enjoy your parameters and coffee the same way: <strong>strong</strong>.
Your code will be more defensive and the data will be cleaner in the long run.</p>
<br>
<h3>Additional Resources:</h3>
<p><a href = "http://edgeapi.rubyonrails.org/classes/ActionController/StrongParameters.html" target="_blank">Documentation</a><br>
<a href = "http://weblog.rubyonrails.org/2012/3/21/strong-parameters/" target="_blank"> DHH’s Blog Post</a><br>
<a href ="http://pivotallabs.com/rails-4-testing-strong-parameters/" target="_blank">Pivotal Labs on Testing Strong Params</a><br>
<a href= "https://github.com/rails/strong_parameters" target="_blank"> Strong Params Gem for Earlier Ruby Versions</a><br></p>
]]></content>
</entry>
<entry>
<title type="html"><![CDATA[Yield! In the Name of Blocks]]></title>
<link href="http://gregeng.github.io/blog/2013/10/23/yield-in-the-name-of-blocks/"/>
<updated>2013-10-23T08:38:00-07:00</updated>
<id>http://gregeng.github.io/blog/2013/10/23/yield-in-the-name-of-blocks</id>
<content type="html"><![CDATA[<p>Let’s think it <a href="http://www.metrolyrics.com/stop-in-the-name-of-love-lyrics-the-supremes.html" target="_blank">over</a>…</p>
<p>In an earlier <a href="http://gregeng.github.io/blog/2013/10/09/abstraction-and-3-iterators/" target="_blank">post</a>, I talked about a few Ruby iterators and how they abstract to become useful tools. As promised, I’m going to further break them down in order to describe the conept of <code>yield</code> in Ruby.</p>
<p>In Ruby, methods are functions that allow code to interact with all different pieces of the program. Compared to spoken languages, you can think of methods as the verbs which connect to nouns and other words to form sentences. Methods are able to receive a code <code>block</code> which unlocks limitless potential.
When defining our own methods, the magic of <code>yield</code> comes into play. If a method expects a block, it can invoke it by using <code>yield</code>.</p>
<p>For example:</p>
<figure class='code'><figcaption><span></span></figcaption><div class="highlight"><table><tr><td class="gutter"><pre class="line-numbers"><span class='line-number'>1</span>
<span class='line-number'>2</span>
<span class='line-number'>3</span>
<span class='line-number'>4</span>
<span class='line-number'>5</span>
<span class='line-number'>6</span>
<span class='line-number'>7</span>
<span class='line-number'>8</span>
<span class='line-number'>9</span>
<span class='line-number'>10</span>
<span class='line-number'>11</span>
</pre></td><td class='code'><pre><code class='ruby'><span class='line'><span class="k">class</span> <span class="nc">Weather</span>
</span><span class='line'> <span class="k">def</span> <span class="nf">initialize</span><span class="p">(</span><span class="n">type</span><span class="p">)</span>
</span><span class='line'> <span class="vi">@type</span> <span class="o">=</span> <span class="n">type</span>
</span><span class='line'> <span class="k">end</span>
</span><span class='line'>
</span><span class='line'> <span class="k">def</span> <span class="nf">forecast</span>
</span><span class='line'> <span class="k">yield</span><span class="p">(</span><span class="vi">@type</span><span class="p">)</span>
</span><span class='line'> <span class="k">end</span>
</span><span class='line'><span class="k">end</span>
</span><span class='line'>
</span><span class='line'><span class="n">today</span> <span class="o">=</span> <span class="no">Weather</span><span class="o">.</span><span class="n">new</span><span class="p">(</span><span class="s2">"hot"</span><span class="p">)</span>
</span></code></pre></td></tr></table></div></figure>
<p>Here I am defining a weather class that takes an argument at instantiation. I’ve also defined a method <code>forecast</code> that will take any block given and pass it the argument.</p>
<figure class='code'><figcaption><span></span></figcaption><div class="highlight"><table><tr><td class="gutter"><pre class="line-numbers"><span class='line-number'>1</span>
<span class='line-number'>2</span>
<span class='line-number'>3</span>
<span class='line-number'>4</span>
<span class='line-number'>5</span>
</pre></td><td class='code'><pre><code class='ruby'><span class='line'><span class="n">today</span><span class="o">.</span><span class="n">forecast</span> <span class="k">do</span> <span class="o">|</span><span class="n">type</span><span class="o">|</span>
</span><span class='line'> <span class="nb">puts</span> <span class="s2">"It's going to be </span><span class="si">#{</span><span class="n">type</span><span class="si">}</span><span class="s2">!"</span>
</span><span class='line'><span class="k">end</span>
</span><span class='line'>
</span><span class='line'><span class="c1"># => It's going to be hot!</span>
</span></code></pre></td></tr></table></div></figure>
<p>As you can see, I’ve interpolated the variable with a friendly little forecast sentence.</p>
<p>But I could just as easily use a different block to perform a different function.</p>
<figure class='code'><figcaption><span></span></figcaption><div class="highlight"><table><tr><td class="gutter"><pre class="line-numbers"><span class='line-number'>1</span>
<span class='line-number'>2</span>
<span class='line-number'>3</span>
<span class='line-number'>4</span>
<span class='line-number'>5</span>
</pre></td><td class='code'><pre><code class='ruby'><span class='line'><span class="n">today</span><span class="o">.</span><span class="n">forecast</span> <span class="k">do</span> <span class="o">|</span><span class="n">type</span><span class="o">|</span>
</span><span class='line'> <span class="nb">puts</span> <span class="s2">"It's going to be </span><span class="si">#{</span><span class="n">type</span><span class="o">.</span><span class="n">upcase</span><span class="si">}</span><span class="s2">, </span><span class="si">#{</span><span class="n">type</span><span class="o">.</span><span class="n">upcase</span><span class="si">}</span><span class="s2">, </span><span class="si">#{</span><span class="n">type</span><span class="o">.</span><span class="n">upcase</span><span class="si">}</span><span class="s2">!"</span>
</span><span class='line'><span class="k">end</span>
</span><span class='line'>
</span><span class='line'><span class="c1"># => It's going to be HOT, HOT, HOT!</span>
</span></code></pre></td></tr></table></div></figure>
<p>In this case… I am loudly saying it’s going to be <em>fairly</em> warm.</p>
<p>Building on this idea, you can see that it essentially allows any method to easily become an iterator. Here is another look at the iterators described in my previous post: <code>each</code>, <code>collect</code>, <code>select</code>.</p>
<p><code>each</code> dissected:</p>
<figure class='code'><figcaption><span></span></figcaption><div class="highlight"><table><tr><td class="gutter"><pre class="line-numbers"><span class='line-number'>1</span>
<span class='line-number'>2</span>
<span class='line-number'>3</span>
<span class='line-number'>4</span>
<span class='line-number'>5</span>
<span class='line-number'>6</span>
<span class='line-number'>7</span>
<span class='line-number'>8</span>
<span class='line-number'>9</span>
<span class='line-number'>10</span>
<span class='line-number'>11</span>
<span class='line-number'>12</span>
<span class='line-number'>13</span>
<span class='line-number'>14</span>
<span class='line-number'>15</span>
<span class='line-number'>16</span>
<span class='line-number'>17</span>
<span class='line-number'>18</span>
<span class='line-number'>19</span>
</pre></td><td class='code'><pre><code class='ruby'><span class='line'><span class="k">def</span> <span class="nf">my_each</span><span class="p">(</span><span class="n">array</span><span class="p">)</span>
</span><span class='line'> <span class="n">i</span> <span class="o">=</span> <span class="mi">0</span>
</span><span class='line'> <span class="k">while</span> <span class="n">i</span> <span class="o"><</span> <span class="n">array</span><span class="o">.</span><span class="n">length</span>
</span><span class='line'> <span class="k">yield</span><span class="p">(</span><span class="n">array</span><span class="o">[</span><span class="n">i</span><span class="o">]</span><span class="p">)</span>
</span><span class='line'> <span class="n">i</span> <span class="o">+=</span> <span class="mi">1</span>
</span><span class='line'> <span class="k">end</span>
</span><span class='line'> <span class="n">array</span>
</span><span class='line'><span class="k">end</span>
</span><span class='line'>
</span><span class='line'><span class="n">my_each</span><span class="p">(</span><span class="o">[</span><span class="mi">1</span><span class="p">,</span><span class="mi">2</span><span class="p">,</span><span class="mi">3</span><span class="p">,</span><span class="mi">4</span><span class="p">,</span><span class="mi">5</span><span class="o">]</span><span class="p">)</span> <span class="p">{</span> <span class="o">|</span><span class="n">x</span><span class="o">|</span> <span class="nb">puts</span> <span class="n">x</span> <span class="o">*</span> <span class="n">x</span> <span class="p">}</span>
</span><span class='line'>
</span><span class='line'><span class="c1"># OUTPUT:</span>
</span><span class='line'><span class="c1"># 1</span>
</span><span class='line'><span class="c1"># 4</span>
</span><span class='line'><span class="c1"># 9</span>
</span><span class='line'><span class="c1"># 16</span>
</span><span class='line'><span class="c1"># 25</span>
</span><span class='line'>
</span><span class='line'><span class="o">=></span> <span class="o">[</span><span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">,</span> <span class="mi">3</span><span class="p">,</span> <span class="mi">4</span><span class="p">,</span> <span class="mi">5</span><span class="o">]</span>
</span></code></pre></td></tr></table></div></figure>
<p><code>collect</code> dissected:</p>
<figure class='code'><figcaption><span></span></figcaption><div class="highlight"><table><tr><td class="gutter"><pre class="line-numbers"><span class='line-number'>1</span>
<span class='line-number'>2</span>
<span class='line-number'>3</span>
<span class='line-number'>4</span>
<span class='line-number'>5</span>
<span class='line-number'>6</span>
<span class='line-number'>7</span>
<span class='line-number'>8</span>
<span class='line-number'>9</span>
<span class='line-number'>10</span>
<span class='line-number'>11</span>
<span class='line-number'>12</span>
<span class='line-number'>13</span>
</pre></td><td class='code'><pre><code class='ruby'><span class='line'><span class="k">def</span> <span class="nf">my_collect</span><span class="p">(</span><span class="n">array</span><span class="p">)</span>
</span><span class='line'> <span class="n">i</span> <span class="o">=</span> <span class="mi">0</span>
</span><span class='line'> <span class="n">collect</span> <span class="o">=</span> <span class="o">[]</span>
</span><span class='line'> <span class="k">while</span> <span class="n">i</span> <span class="o"><</span> <span class="n">array</span><span class="o">.</span><span class="n">length</span>
</span><span class='line'> <span class="n">collect</span> <span class="o"><<</span> <span class="p">(</span><span class="k">yield</span><span class="p">(</span><span class="n">array</span><span class="o">[</span><span class="n">i</span><span class="o">]</span><span class="p">))</span>
</span><span class='line'> <span class="n">i</span> <span class="o">+=</span> <span class="mi">1</span>
</span><span class='line'> <span class="k">end</span>
</span><span class='line'> <span class="n">collect</span>
</span><span class='line'><span class="k">end</span>
</span><span class='line'>
</span><span class='line'><span class="n">collect_results</span> <span class="o">=</span> <span class="n">my_collect</span><span class="p">(</span><span class="o">[</span><span class="mi">1</span><span class="p">,</span><span class="mi">2</span><span class="p">,</span><span class="mi">3</span><span class="p">,</span><span class="mi">4</span><span class="p">,</span><span class="mi">5</span><span class="o">]</span><span class="p">)</span> <span class="p">{</span> <span class="o">|</span><span class="n">x</span><span class="o">|</span> <span class="n">x</span> <span class="o">*</span> <span class="n">x</span> <span class="p">}</span>
</span><span class='line'>
</span><span class='line'><span class="o">=></span> <span class="o">[</span><span class="mi">1</span><span class="p">,</span> <span class="mi">4</span><span class="p">,</span> <span class="mi">9</span><span class="p">,</span> <span class="mi">16</span><span class="p">,</span> <span class="mi">25</span><span class="o">]</span>
</span></code></pre></td></tr></table></div></figure>
<p><code>select</code> dissected:</p>
<figure class='code'><figcaption><span></span></figcaption><div class="highlight"><table><tr><td class="gutter"><pre class="line-numbers"><span class='line-number'>1</span>
<span class='line-number'>2</span>
<span class='line-number'>3</span>
<span class='line-number'>4</span>
<span class='line-number'>5</span>
<span class='line-number'>6</span>
<span class='line-number'>7</span>
<span class='line-number'>8</span>
<span class='line-number'>9</span>
<span class='line-number'>10</span>
<span class='line-number'>11</span>
<span class='line-number'>12</span>
<span class='line-number'>13</span>
<span class='line-number'>14</span>
<span class='line-number'>15</span>
</pre></td><td class='code'><pre><code class='ruby'><span class='line'><span class="k">def</span> <span class="nf">my_select</span><span class="p">(</span><span class="n">array</span><span class="p">)</span>
</span><span class='line'> <span class="n">i</span> <span class="o">=</span> <span class="mi">0</span>
</span><span class='line'> <span class="nb">select</span> <span class="o">=</span> <span class="o">[]</span>
</span><span class='line'> <span class="k">while</span> <span class="n">i</span> <span class="o"><</span> <span class="n">array</span><span class="o">.</span><span class="n">length</span>
</span><span class='line'> <span class="k">if</span> <span class="p">(</span><span class="k">yield</span><span class="p">(</span><span class="n">array</span><span class="o">[</span><span class="n">i</span><span class="o">]</span><span class="p">))</span>
</span><span class='line'> <span class="nb">select</span> <span class="o"><<</span> <span class="n">array</span><span class="o">[</span><span class="n">i</span><span class="o">]</span>
</span><span class='line'> <span class="k">end</span>
</span><span class='line'> <span class="n">i</span><span class="o">+=</span><span class="mi">1</span>
</span><span class='line'> <span class="k">end</span>
</span><span class='line'> <span class="nb">select</span>
</span><span class='line'><span class="k">end</span>
</span><span class='line'>
</span><span class='line'><span class="n">select_results</span> <span class="o">=</span> <span class="n">my_select</span><span class="p">(</span><span class="o">[</span><span class="mi">1</span><span class="p">,</span><span class="mi">2</span><span class="p">,</span><span class="mi">3</span><span class="p">,</span><span class="mi">4</span><span class="p">,</span><span class="mi">5</span><span class="o">]</span><span class="p">)</span> <span class="p">{</span> <span class="o">|</span><span class="n">x</span><span class="o">|</span> <span class="n">x</span> <span class="o">==</span> <span class="mi">3</span> <span class="p">}</span>
</span><span class='line'>
</span><span class='line'><span class="o">=></span> <span class="o">[</span><span class="mi">3</span><span class="o">]</span>
</span></code></pre></td></tr></table></div></figure>
<p>BONUS <code>none?</code> dissected:</p>
<figure class='code'><figcaption><span></span></figcaption><div class="highlight"><table><tr><td class="gutter"><pre class="line-numbers"><span class='line-number'>1</span>
<span class='line-number'>2</span>
<span class='line-number'>3</span>
<span class='line-number'>4</span>
<span class='line-number'>5</span>
<span class='line-number'>6</span>
<span class='line-number'>7</span>
<span class='line-number'>8</span>
<span class='line-number'>9</span>
<span class='line-number'>10</span>
<span class='line-number'>11</span>
<span class='line-number'>12</span>
<span class='line-number'>13</span>
<span class='line-number'>14</span>
<span class='line-number'>15</span>
<span class='line-number'>16</span>
<span class='line-number'>17</span>
<span class='line-number'>18</span>
</pre></td><td class='code'><pre><code class='ruby'><span class='line'><span class="k">def</span> <span class="nf">my_none?</span><span class="p">(</span><span class="n">array</span><span class="p">)</span>
</span><span class='line'> <span class="n">i</span> <span class="o">=</span> <span class="mi">0</span>
</span><span class='line'> <span class="k">while</span> <span class="n">i</span> <span class="o"><</span> <span class="n">array</span><span class="o">.</span><span class="n">length</span>
</span><span class='line'> <span class="k">if</span> <span class="p">(</span><span class="k">yield</span><span class="p">(</span><span class="n">array</span><span class="o">[</span><span class="n">i</span><span class="o">]</span><span class="p">))</span>
</span><span class='line'> <span class="k">return</span> <span class="kp">false</span>
</span><span class='line'> <span class="k">end</span>
</span><span class='line'> <span class="n">i</span> <span class="o">+=</span> <span class="mi">1</span>
</span><span class='line'> <span class="k">end</span>
</span><span class='line'> <span class="kp">true</span>
</span><span class='line'><span class="k">end</span>
</span><span class='line'>
</span><span class='line'><span class="n">my_none?</span><span class="p">(</span><span class="o">[</span><span class="mi">1</span><span class="p">,</span><span class="mi">2</span><span class="p">,</span><span class="mi">3</span><span class="o">]</span><span class="p">)</span> <span class="p">{</span> <span class="o">|</span><span class="n">x</span><span class="o">|</span> <span class="n">x</span> <span class="o">==</span> <span class="mi">3</span> <span class="p">}</span>
</span><span class='line'>
</span><span class='line'><span class="o">=></span> <span class="kp">false</span>
</span><span class='line'>
</span><span class='line'><span class="n">my_none?</span><span class="p">(</span><span class="o">[</span><span class="mi">1</span><span class="p">,</span><span class="mi">2</span><span class="p">,</span><span class="mi">3</span><span class="o">]</span><span class="p">)</span> <span class="p">{</span> <span class="o">|</span><span class="n">x</span><span class="o">|</span> <span class="n">x</span> <span class="o">==</span> <span class="mi">4</span> <span class="p">}</span>
</span><span class='line'>
</span><span class='line'><span class="o">=></span> <span class="kp">true</span>
</span></code></pre></td></tr></table></div></figure>
<p>BONUS <code>include?</code> dissected:</p>
<figure class='code'><figcaption><span></span></figcaption><div class="highlight"><table><tr><td class="gutter"><pre class="line-numbers"><span class='line-number'>1</span>
<span class='line-number'>2</span>
<span class='line-number'>3</span>
<span class='line-number'>4</span>
<span class='line-number'>5</span>
<span class='line-number'>6</span>
<span class='line-number'>7</span>
<span class='line-number'>8</span>
<span class='line-number'>9</span>
<span class='line-number'>10</span>
<span class='line-number'>11</span>
<span class='line-number'>12</span>
<span class='line-number'>13</span>
<span class='line-number'>14</span>
<span class='line-number'>15</span>
</pre></td><td class='code'><pre><code class='ruby'><span class='line'><span class="k">def</span> <span class="nf">my_include?</span><span class="p">(</span><span class="n">array</span><span class="p">)</span>
</span><span class='line'> <span class="n">i</span> <span class="o">=</span> <span class="mi">0</span>
</span><span class='line'> <span class="k">while</span> <span class="n">i</span> <span class="o"><</span> <span class="n">array</span><span class="o">.</span><span class="n">length</span>
</span><span class='line'> <span class="k">if</span> <span class="p">(</span><span class="k">yield</span><span class="p">(</span><span class="n">array</span><span class="o">[</span><span class="n">i</span><span class="o">]</span><span class="p">))</span>
</span><span class='line'> <span class="k">return</span> <span class="kp">true</span>
</span><span class='line'> <span class="k">end</span>
</span><span class='line'> <span class="n">i</span> <span class="o">+=</span> <span class="mi">1</span>
</span><span class='line'> <span class="k">end</span>
</span><span class='line'> <span class="kp">false</span>
</span><span class='line'><span class="k">end</span>
</span><span class='line'>
</span><span class='line'><span class="n">my_include?</span><span class="p">(</span><span class="o">[</span><span class="mi">1</span><span class="p">,</span><span class="mi">2</span><span class="p">,</span><span class="mi">3</span><span class="o">]</span><span class="p">)</span> <span class="p">{</span> <span class="o">|</span><span class="n">x</span><span class="o">|</span> <span class="n">x</span> <span class="o">==</span> <span class="mi">3</span> <span class="p">}</span>
</span><span class='line'><span class="o">=></span> <span class="kp">true</span>
</span><span class='line'><span class="n">my_include?</span><span class="p">(</span><span class="o">[</span><span class="mi">1</span><span class="p">,</span><span class="mi">2</span><span class="p">,</span><span class="mi">3</span><span class="o">]</span><span class="p">)</span> <span class="p">{</span> <span class="o">|</span><span class="n">x</span><span class="o">|</span> <span class="n">x</span> <span class="o">==</span> <span class="mi">4</span> <span class="p">}</span>
</span><span class='line'><span class="o">=></span> <span class="kp">false</span>
</span></code></pre></td></tr></table></div></figure>
<p>These examples are simple and isolated, but <code>yield</code> truly provides myriad possibilities when building sophisticated programs. To prove it, check out this <a href="http://rubylearning.com/blog/2010/11/30/how-do-i-build-dsls-with-yield-and-instance_eval/" target="_blank">blog post</a> by Michael Bleigh where he described constructing eloquent looking code to design a DSL (Domain Specific Language) with the help of <code>yield</code>.</p>
<p>Have you ever used <code>yield</code> to do something clever or noteworthy? Sound off in the comments!</p>
]]></content>
</entry>
<entry>
<title type="html"><![CDATA[Abstraction and 3 Helpful Ruby Iterators]]></title>
<link href="http://gregeng.github.io/blog/2013/10/09/abstraction-and-3-iterators/"/>
<updated>2013-10-09T18:30:00-07:00</updated>
<id>http://gregeng.github.io/blog/2013/10/09/abstraction-and-3-iterators</id>
<content type="html"><![CDATA[<p>I’ve never been a big fan of modern art. Some pieces are so abstract that I don’t really get the point – and I know I’m not the only <a href="http://www.buzzfeed.com/jenlewis/quiz-can-you-tell-the-difference-between-modern-art-and-art
" target="_blank">one</a>.</p>
<p>But in programming, abstraction is different. It makes for more eloquent and productive code by concealing complexity. Let’s witness abstraction by stepping through 3 related methods:
<code>each</code>, <code>collect</code> & <code>select</code>.</p>
<p>The <code>each</code> method:</p>
<figure class='code'><figcaption><span></span></figcaption><div class="highlight"><table><tr><td class="gutter"><pre class="line-numbers"><span class='line-number'>1</span>
<span class='line-number'>2</span>
<span class='line-number'>3</span>
<span class='line-number'>4</span>
<span class='line-number'>5</span>
<span class='line-number'>6</span>
<span class='line-number'>7</span>
<span class='line-number'>8</span>
<span class='line-number'>9</span>
</pre></td><td class='code'><pre><code class='ruby'><span class='line'><span class="n">numbers_array</span> <span class="o">=</span> <span class="o">[</span><span class="mi">1</span><span class="p">,</span><span class="mi">2</span><span class="p">,</span><span class="mi">3</span><span class="p">,</span><span class="mi">4</span><span class="p">,</span><span class="mi">5</span><span class="p">,</span><span class="mi">6</span><span class="p">,</span><span class="mi">7</span><span class="p">,</span><span class="mi">8</span><span class="p">,</span><span class="mi">9</span><span class="p">,</span><span class="mi">10</span><span class="o">]</span>
</span><span class='line'>
</span><span class='line'> <span class="n">numbers_array</span><span class="o">.</span><span class="n">each</span> <span class="k">do</span> <span class="o">|</span><span class="n">x</span><span class="o">|</span>
</span><span class='line'> <span class="nb">print</span> <span class="s2">"</span><span class="si">#{</span><span class="n">x</span> <span class="o">*</span> <span class="mi">2</span><span class="si">}</span><span class="s2"> "</span>
</span><span class='line'> <span class="k">end</span>
</span><span class='line'>
</span><span class='line'><span class="c1">#output: 2 4 6 8 10 12 14 16 18 20</span>
</span><span class='line'>
</span><span class='line'><span class="n">numbers_array</span> <span class="o">=</span> <span class="o">[</span><span class="mi">1</span><span class="p">,</span><span class="mi">2</span><span class="p">,</span><span class="mi">3</span><span class="p">,</span><span class="mi">4</span><span class="p">,</span><span class="mi">5</span><span class="p">,</span><span class="mi">6</span><span class="p">,</span><span class="mi">7</span><span class="p">,</span><span class="mi">8</span><span class="p">,</span><span class="mi">9</span><span class="p">,</span><span class="mi">10</span><span class="o">]</span>
</span></code></pre></td></tr></table></div></figure>
<p>The <code>each</code> method iterates through individual elements in the array and returns the original array untouched.</p>
<p>When I first learned the <code>each</code> method, I used it almost exclusively when working with arrays to make the computer do alot of the leg work for me.</p>
<p><a href="http://en.wikipedia.org/wiki/Abraham_Maslow" target="_blank">Abraham Maslow</a> explains this consequence:</p>
<blockquote><p>…if all you have is a hammer, everything looks like a nail.</p></blockquote>
<p>However, since the <code>each</code> method does not change the original array, I started writing alot of code that looks like this:</p>
<figure class='code'><figcaption><span></span></figcaption><div class="highlight"><table><tr><td class="gutter"><pre class="line-numbers"><span class='line-number'>1</span>
<span class='line-number'>2</span>
<span class='line-number'>3</span>
<span class='line-number'>4</span>
<span class='line-number'>5</span>
<span class='line-number'>6</span>
<span class='line-number'>7</span>
<span class='line-number'>8</span>
<span class='line-number'>9</span>
<span class='line-number'>10</span>
<span class='line-number'>11</span>
<span class='line-number'>12</span>
<span class='line-number'>13</span>
<span class='line-number'>14</span>
<span class='line-number'>15</span>
<span class='line-number'>16</span>
</pre></td><td class='code'><pre><code class='ruby'><span class='line'><span class="n">numbers_array</span> <span class="o">=</span> <span class="o">[</span><span class="mi">1</span><span class="p">,</span><span class="mi">2</span><span class="p">,</span><span class="mi">3</span><span class="p">,</span><span class="mi">4</span><span class="p">,</span><span class="mi">5</span><span class="p">,</span><span class="mi">6</span><span class="p">,</span><span class="mi">7</span><span class="p">,</span><span class="mi">8</span><span class="p">,</span><span class="mi">9</span><span class="p">,</span><span class="mi">10</span><span class="o">]</span>
</span><span class='line'><span class="n">odds_and_ends</span> <span class="o">=</span> <span class="o">[]</span>
</span><span class='line'>
</span><span class='line'> <span class="n">numbers_array</span><span class="o">.</span><span class="n">each</span> <span class="k">do</span> <span class="o">|</span><span class="n">x</span><span class="o">|</span>
</span><span class='line'>
</span><span class='line'> <span class="k">if</span> <span class="n">x</span> <span class="o">%</span> <span class="mi">2</span> <span class="o">!=</span> <span class="mi">0</span>
</span><span class='line'> <span class="n">odds_and_ends</span> <span class="o"><<</span> <span class="kp">true</span>
</span><span class='line'> <span class="k">else</span> <span class="n">x</span> <span class="o">%</span> <span class="mi">2</span> <span class="o">==</span> <span class="mi">0</span>
</span><span class='line'> <span class="n">odds_and_ends</span> <span class="o"><<</span> <span class="kp">false</span>
</span><span class='line'> <span class="k">end</span>
</span><span class='line'>
</span><span class='line'> <span class="k">end</span>
</span><span class='line'>
</span><span class='line'><span class="n">odds_and_ends</span>
</span><span class='line'>
</span><span class='line'><span class="o">=></span> <span class="o">[</span><span class="kp">true</span><span class="p">,</span> <span class="kp">false</span><span class="p">,</span> <span class="kp">true</span><span class="p">,</span> <span class="kp">false</span><span class="p">,</span> <span class="kp">true</span><span class="p">,</span> <span class="kp">false</span><span class="p">,</span> <span class="kp">true</span><span class="p">,</span> <span class="kp">false</span><span class="p">,</span> <span class="kp">true</span><span class="p">,</span> <span class="kp">false</span><span class="o">]</span>
</span></code></pre></td></tr></table></div></figure>
<p>Here, I am creating a new empty array, just so I can shovel items into it with the <code>each</code> method. If this feels bulky to you, that’s because it is! Programmers might say this pattern reeks of <em>code smell</em>.</p>
<p>The ruby <code>collect</code> method is a better tool for the job, and it is just an abstraction of the <code>each</code> method.</p>
<p>Here is <code>collect</code> using the example from above:</p>
<figure class='code'><figcaption><span></span></figcaption><div class="highlight"><table><tr><td class="gutter"><pre class="line-numbers"><span class='line-number'>1</span>
<span class='line-number'>2</span>
<span class='line-number'>3</span>
<span class='line-number'>4</span>
<span class='line-number'>5</span>
<span class='line-number'>6</span>
<span class='line-number'>7</span>
<span class='line-number'>8</span>
<span class='line-number'>9</span>
</pre></td><td class='code'><pre><code class='ruby'><span class='line'><span class="n">odds_and_ends</span> <span class="o">=</span> <span class="o">[</span><span class="mi">1</span><span class="p">,</span><span class="mi">2</span><span class="p">,</span><span class="mi">3</span><span class="p">,</span><span class="mi">4</span><span class="p">,</span><span class="mi">5</span><span class="p">,</span><span class="mi">6</span><span class="p">,</span><span class="mi">7</span><span class="p">,</span><span class="mi">8</span><span class="p">,</span><span class="mi">9</span><span class="p">,</span><span class="mi">10</span><span class="o">].</span><span class="n">collect</span> <span class="k">do</span> <span class="o">|</span><span class="n">x</span><span class="o">|</span>
</span><span class='line'> <span class="k">if</span> <span class="n">x</span> <span class="o">%</span> <span class="mi">2</span> <span class="o">!=</span> <span class="mi">0</span>
</span><span class='line'> <span class="kp">true</span>
</span><span class='line'> <span class="k">else</span> <span class="n">x</span> <span class="o">%</span> <span class="mi">2</span> <span class="o">==</span> <span class="mi">0</span>
</span><span class='line'> <span class="kp">false</span>
</span><span class='line'> <span class="k">end</span>
</span><span class='line'><span class="k">end</span>
</span><span class='line'>
</span><span class='line'><span class="o">=></span> <span class="o">[</span><span class="kp">true</span><span class="p">,</span> <span class="kp">false</span><span class="p">,</span> <span class="kp">true</span><span class="p">,</span> <span class="kp">false</span><span class="p">,</span> <span class="kp">true</span><span class="p">,</span> <span class="kp">false</span><span class="p">,</span> <span class="kp">true</span><span class="p">,</span> <span class="kp">false</span><span class="p">,</span> <span class="kp">true</span><span class="p">,</span> <span class="kp">false</span><span class="o">]</span>
</span></code></pre></td></tr></table></div></figure>
<p>Note that the <code>collect</code> method returns a <strong>new</strong> array which I have set equal to “odds_and_ends.”</p>
<p>But what if we only wanted to return a <em>part</em> of the array if it matches certain criteria? In that case, <code>collect</code> no longer the best option.</p>
<p>As you might have guessed, the ruby <code>select</code> method is an abstraction of the <code>collect</code> method. It also returns a new array, with an implicit <em>if</em> clause built in.</p>
<p>Continuing with our example…</p>
<p>If we were to use <code>collect</code>, it would return a messy array including nil values…</p>
<figure class='code'><figcaption><span></span></figcaption><div class="highlight"><table><tr><td class="gutter"><pre class="line-numbers"><span class='line-number'>1</span>
<span class='line-number'>2</span>
<span class='line-number'>3</span>
<span class='line-number'>4</span>
<span class='line-number'>5</span>
<span class='line-number'>6</span>
<span class='line-number'>7</span>
</pre></td><td class='code'><pre><code class='ruby'><span class='line'><span class="n">odds_and_ends</span> <span class="o">=</span> <span class="o">[</span><span class="mi">1</span><span class="p">,</span><span class="mi">2</span><span class="p">,</span><span class="mi">3</span><span class="p">,</span><span class="mi">4</span><span class="p">,</span><span class="mi">5</span><span class="p">,</span><span class="mi">6</span><span class="p">,</span><span class="mi">7</span><span class="p">,</span><span class="mi">8</span><span class="p">,</span><span class="mi">9</span><span class="p">,</span><span class="mi">10</span><span class="o">].</span><span class="n">collect</span> <span class="k">do</span> <span class="o">|</span><span class="n">x</span><span class="o">|</span>
</span><span class='line'> <span class="k">if</span> <span class="n">x</span> <span class="o">%</span> <span class="mi">2</span> <span class="o">!=</span> <span class="mi">0</span>
</span><span class='line'> <span class="n">x</span>
</span><span class='line'> <span class="k">end</span>
</span><span class='line'><span class="k">end</span>
</span><span class='line'>
</span><span class='line'><span class="o">=></span> <span class="o">[</span><span class="mi">1</span><span class="p">,</span> <span class="kp">nil</span><span class="p">,</span> <span class="mi">3</span><span class="p">,</span> <span class="kp">nil</span><span class="p">,</span> <span class="mi">5</span><span class="p">,</span> <span class="kp">nil</span><span class="p">,</span> <span class="mi">7</span><span class="p">,</span> <span class="kp">nil</span><span class="p">,</span> <span class="mi">9</span><span class="p">,</span> <span class="kp">nil</span><span class="o">]</span>
</span></code></pre></td></tr></table></div></figure>
<p>…while <code>select</code> gets the job done more cleanly. It uses the implicit if to return only values matching the specified logic:</p>
<figure class='code'><figcaption><span></span></figcaption><div class="highlight"><table><tr><td class="gutter"><pre class="line-numbers"><span class='line-number'>1</span>
<span class='line-number'>2</span>
<span class='line-number'>3</span>
<span class='line-number'>4</span>
<span class='line-number'>5</span>
</pre></td><td class='code'><pre><code class='ruby'><span class='line'><span class="n">odds_and_ends</span> <span class="o">=</span> <span class="o">[</span><span class="mi">1</span><span class="p">,</span><span class="mi">2</span><span class="p">,</span><span class="mi">3</span><span class="p">,</span><span class="mi">4</span><span class="p">,</span><span class="mi">5</span><span class="p">,</span><span class="mi">6</span><span class="p">,</span><span class="mi">7</span><span class="p">,</span><span class="mi">8</span><span class="p">,</span><span class="mi">9</span><span class="p">,</span><span class="mi">10</span><span class="o">].</span><span class="n">select</span> <span class="k">do</span> <span class="o">|</span><span class="n">x</span><span class="o">|</span>
</span><span class='line'> <span class="n">x</span> <span class="o">%</span> <span class="mi">2</span> <span class="o">!=</span> <span class="mi">0</span>
</span><span class='line'><span class="k">end</span>
</span><span class='line'>
</span><span class='line'><span class="o">=></span> <span class="o">[</span><span class="mi">1</span><span class="p">,</span> <span class="mi">3</span><span class="p">,</span> <span class="mi">5</span><span class="p">,</span> <span class="mi">7</span><span class="p">,</span> <span class="mi">9</span><span class="o">]</span>
</span></code></pre></td></tr></table></div></figure>
<p>So remember, abstraction is your friend!</p>
<p>To recap: <code>select</code> is an abstraction of <code>collect</code> which is just an abstraction of <code>each</code>. Use them to <a href="http://images.wikia.com/richmoreacademy/images/0/07/Pine-tree-car-air-freshener.gif" target="_blank">freshen</a> up any and all code smell. I’m still working to make sure I choose the right methods.</p>