SecureRandom.html

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title: SecureRandom
layout: default
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            <span>Ruby on Rails 8.0.0</span><br />
        
        <div class="type">Module</div>
        <h1>
            SecureRandom
            
        </h1>
        <ul class="files">
            
            <li><a href="../files/activesupport/lib/active_support/core_ext/securerandom_rb.html">activesupport/lib/active_support/core_ext/securerandom.rb</a></li>
            
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        <div id="content">
  

  

  
  


  

  
    <h2 id="methods">Methods</h2>
    <ul>
      
        <li>
          <a href="#method-c-base36">base36</a>
        </li>
      
        <li>
          <a href="#method-c-base58">base58</a>
        </li>
      
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      <!-- Section constants -->
      <h2 id="constants">Constants</h2>
      <table border='0' cellpadding='5'>
        
          <tr valign='top'>
            <td class="attr-name">BASE36_ALPHABET</td>
            <td>=</td>
            <td class="attr-value">(&quot;0&quot;..&quot;9&quot;).to_a + (&quot;a&quot;..&quot;z&quot;).to_a</td>
          </tr>
          
        
          <tr valign='top'>
            <td class="attr-name">BASE58_ALPHABET</td>
            <td>=</td>
            <td class="attr-value">(&quot;0&quot;..&quot;9&quot;).to_a + (&quot;A&quot;..&quot;Z&quot;).to_a + (&quot;a&quot;..&quot;z&quot;).to_a - [&quot;0&quot;, &quot;O&quot;, &quot;I&quot;, &quot;l&quot;]</td>
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    <!-- Methods -->
    
      <h2 id="class-public-methods">Class Public methods</h2>
      
        <div class="method">
          <h3 id="method-c-base36">
            
              base36(n = 16)
            
          </h3>

          
            <div class="description">
              <p><a href="SecureRandom.html#method-c-base36"><code>SecureRandom.base36</code></a> generates a random base36 string in lowercase.</p>

<p>The argument <em>n</em> specifies the length of the random string to be generated.</p>

<p>If <em>n</em> is not specified or is <code>nil</code>, 16 is assumed. It may be larger in the future. This method can be used over <code>base58</code> if a deterministic case key is necessary.</p>

<p>The result will contain alphanumeric characters in lowercase.</p>

<pre><code>p SecureRandom.base36 # =&gt; &quot;4kugl2pdqmscqtje&quot;
p SecureRandom.base36(24) # =&gt; &quot;77tmhrhjfvfdwodq8w7ev2m7&quot;
</code></pre>
            </div>
          

          

          

          
          
            <details class="method__source">
              <summary>
                <span class="label">📝 Source code</span>
              </summary>

              <pre><code class="ruby"># File activesupport/lib/active_support/core_ext/securerandom.rb, line 34
  def self.base36(n = 16)
    SecureRandom.random_bytes(n).unpack(&quot;C*&quot;).map do |byte|
      idx = byte % 64
      idx = SecureRandom.random_number(36) if idx &gt;= 36
      BASE36_ALPHABET[idx]
    end.join
  end</code></pre>
              
                <a href="https://github.com/rails/rails/blob/dd8f7185faeca6ee968a6e9367f6d8601a83b8db/activesupport/lib/active_support/core_ext/securerandom.rb#L34" target="_blank" class="github_url">🔎 See on GitHub</a>
              
            </details>
          
        </div>
        
        <div class="method">
          <h3 id="method-c-base58">
            
              base58(n = 16)
            
          </h3>

          
            <div class="description">
              <p><a href="SecureRandom.html#method-c-base58"><code>SecureRandom.base58</code></a> generates a random base58 string.</p>

<p>The argument <em>n</em> specifies the length of the random string to be generated.</p>

<p>If <em>n</em> is not specified or is <code>nil</code>, 16 is assumed. It may be larger in the future.</p>

<p>The result may contain alphanumeric characters except 0, O, I, and l.</p>

<pre><code>p SecureRandom.base58 # =&gt; &quot;4kUgL2pdQMSCQtjE&quot;
p SecureRandom.base58(24) # =&gt; &quot;77TMHrHJFvFDwodq8w7Ev2m7&quot;
</code></pre>
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            <details class="method__source">
              <summary>
                <span class="label">📝 Source code</span>
              </summary>

              <pre><code class="ruby"># File activesupport/lib/active_support/core_ext/securerandom.rb, line 19
  def self.base58(n = 16)
    SecureRandom.alphanumeric(n, chars: BASE58_ALPHABET)
  end</code></pre>
              
                <a href="https://github.com/rails/rails/blob/dd8f7185faeca6ee968a6e9367f6d8601a83b8db/activesupport/lib/active_support/core_ext/securerandom.rb#L19" target="_blank" class="github_url">🔎 See on GitHub</a>
              
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