Sophisticate readme (#2)

* [terraforming] add only iam_role and s3

* iam_policy_attachment

.circleci/config.yml

@@ -3,13 +3,25 @@ jobs:
   build:
     docker:
       - image: circleci/ruby:2.4.2-jessie-node
+        environment:
+          BUNDLER_VERSION: 2.0.2
     steps:
       - checkout
       - restore_cache:
           keys:
             - v1-dependencies-{{ checksum "Gemfile.lock" }}
             - v1-dependencies-
-      - run: bundle install --path vendor/bundle
+      - run:
+          name: setup bundler
+          command: |
+            sudo gem update --system
+            sudo gem uninstall bundler
+            sudo rm /usr/local/bin/bundle
+            sudo rm /usr/local/bin/bundler
+            sudo gem install bundler
+      - run:
+          name: install
+          command: bundle install --path vendor/bundle
       - save_cache:
           paths:
             - ./vendor/bundle

.gitignore

@@ -10,3 +10,4 @@
 
 # rspec failure tracking
 .rspec_status
+*.gem

.rubocop.yml

@@ -33,6 +33,14 @@ Style/HashSyntax:
   Exclude:
     - 'Rakefile'
 
+# TODO: check again
+Style/IndentArray:
+  Enabled: false
+
+# TODO: check again
+Style/IndentHash:
+  Enabled: false
+
 Style/LineEndConcatenation:
   Enabled: false
 
@@ -74,3 +82,12 @@ Style/CollectionMethods:
 
 Style/PerlBackrefs:
   Enabled: false
+
+Security/Open:
+  Enabled: false
+
+Metrics/BlockLength:
+  Enabled: false
+
+Naming/HeredocDelimiterNaming:
+  Enabled: false

Gemfile.lock

@@ -1,14 +1,47 @@
 PATH
   remote: .
   specs:
-    practice_terraforming (0.1.0)
+    practice_terraforming (0.1.1)
+      aws-sdk-iam (~> 1)
+      aws-sdk-s3 (~> 1)
+      multi_json (~> 1.12.1)
+      thor
 
 GEM
   remote: https://rubygems.org/
   specs:
     ast (2.4.0)
+    aws-eventstream (1.0.3)
+    aws-partitions (1.237.0)
+    aws-sdk-core (3.76.0)
+      aws-eventstream (~> 1.0, >= 1.0.2)
+      aws-partitions (~> 1, >= 1.228.0)
+      aws-sigv4 (~> 1.1)
+      jmespath (~> 1.0)
+    aws-sdk-iam (1.31.0)
+      aws-sdk-core (~> 3, >= 3.71.0)
+      aws-sigv4 (~> 1.1)
+    aws-sdk-kms (1.25.0)
+      aws-sdk-core (~> 3, >= 3.71.0)
+      aws-sigv4 (~> 1.1)
+    aws-sdk-s3 (1.53.0)
+      aws-sdk-core (~> 3, >= 3.71.0)
+      aws-sdk-kms (~> 1)
+      aws-sigv4 (~> 1.1)
+    aws-sigv4 (1.1.0)
+      aws-eventstream (~> 1.0, >= 1.0.2)
+    coveralls (0.8.21)
+      json (>= 1.8, < 3)
+      simplecov (~> 0.14.1)
+      term-ansicolor (~> 1.3)
+      thor (~> 0.19.4)
+      tins (~> 1.6)
     diff-lcs (1.3)
+    docile (1.1.5)
     jaro_winkler (1.5.4)
+    jmespath (1.4.0)
+    json (2.2.0)
+    multi_json (1.12.2)
     parallel (1.18.0)
     parser (2.6.5.0)
       ast (~> 2.4.0)
@@ -35,17 +68,28 @@ GEM
       ruby-progressbar (~> 1.7)
       unicode-display_width (>= 1.4.0, < 1.7)
     ruby-progressbar (1.10.1)
+    simplecov (0.14.1)
+      docile (~> 1.1.0)
+      json (>= 1.8, < 3)
+      simplecov-html (~> 0.10.0)
+    simplecov-html (0.10.2)
+    term-ansicolor (1.7.1)
+      tins (~> 1.0)
+    thor (0.19.4)
+    tins (1.22.0)
     unicode-display_width (1.6.0)
 
 PLATFORMS
   ruby
 
 DEPENDENCIES
-  bundler (~> 1.16)
+  bundler (~> 2.0)
+  coveralls (~> 0.8.13)
   practice_terraforming!
   rake (~> 10.0)
   rspec
   rubocop
+  simplecov (~> 0.14.1)
 
 BUNDLED WITH
-   1.16.6
+   2.0.2

README.md

@@ -43,3 +43,219 @@ The gem is available as open source under the terms of the [MIT License](https:/
 ## Code of Conduct
 
 Everyone interacting in the PracticeTerraforming project’s codebases, issue trackers, chat rooms and mailing lists is expected to follow the [code of conduct](https://github.com/[USERNAME]/practice_terraforming/blob/master/CODE_OF_CONDUCT.md).
+
+# How I created this
+
+## Prepare Gem
+
+```
+bundle gem practice_terraforming
+```
+
+## Entrypoint of practice_terraforming
+
+`bin/practice_terraforming`
+
+CLI command (extended Thor)
+
+## lib/practice_terraforming.rb
+
+`lib/practice_terraforming.rb` just requires all the dependencies
+
+## cli definition
+
+`lib/practice_terraforming/cli.rb`
+
+Basically, just copied from `terraforming/lib/terraforming/cli.rb`. Deleted resources but `iam_role` and `s3`
+
+## AWS Resources (Main logic to generate tfstate/tf)
+
+```
+lib/practice_terraforming/resource/iam_role.rb
+lib/practice_terraforming/resource/s3.rb
+```
+
+Resource file is generated by `script/generate` but need to update `tfstate` method
+
+## Util
+
+`lib/practice_terraforming/util.rb`
+
+Just copied from `terraforming/lib/terraforming/util.rb`
+
+## Gemspec
+
+`practice_terraforming.gemspec`
+
+Wrote dependencies with `spec.add_dependency` and `spec.add_development_dependency`
+
+## Templates
+
+- resource.erb.erb -> tf file
+- resource.rb.erb -> resource class to write logic to generate tf file
+- resource_spec.rb.erb -> spec file
+
+## Spec
+
+|spec file|memo|
+|---|---|
+|spec/fixtures/terraform.tfstate|copied from terraforming|
+|spec/lib/practice_terraforming/cli_spec.rb|copied from terraforming|
+|spec/lib/practice_terraforming/resource/<resource>.rb|generated by `script/generate` but need to write by yourself|
+
+
+## Create Resource
+
+0. generate templates with `script/generate`
+
+```
+script/generate iam_policy_attachment
+==> Generate iam_policy_attachment.rb
+==> Generate iam_policy_attachment_spec.rb
+==> Generate iam_policy_attachment.erb
+
+Add below code by hand.
+
+lib/practice_terraforming.rb:
+
+    require "practice_terraforming/resource/iam_policy_attachment"
+
+lib/practice_terraforming/cli.rb:
+
+    module PracticeTerraforming
+      class CLI < Thor
+
+        # Subcommand name should be acronym.
+        desc "iam_policy_attachment", "Iam Policy Attachment"
+        def iam_policy_attachment
+          execute(PracticeTerraforming::Resource::IamPolicyAttachment, options)
+        end
+
+spec/lib/practice_terraforming/cli_spec.rb:
+
+    module PracticeTerraforming
+      describe CLI do
+        context "resources" do
+        describe "iam_policy_attachment" do
+          let(:klass)   { PracticeTerraforming::Resource::IamPolicyAttachment }
+          let(:command) { :iam_policy_attachment }
+
+          it_behaves_like "CLI examples"
+        end
+```
+
+1. As the message says, add those codes.
+2. `lib/practice_terraforming/resource/iam_policy_attachment.rb`: Change Aws client and write logic in `tfstate` method
+
+    Use aws-sdk-<resource> to get the input data and write the logic to generate tf/tfstate file.
+    1. tf -> only need to update the template file, which appears in the next step
+    2. tfstate -> get resource list using private method, format them into resources and return them
+    3. As for private methods:
+      - module_name_of(<resource>) -> used for module name of terraform to be imported
+      - <api method name, e.g. entities_for_policy> -> get the resource info with aws-sdk
+      - other -> make a list of resources to be used in `tfstate` method
+
+3. `lib/practice_terraforming/template/tf/iam_policy_attachment.erb`: Update the erb based on the corresponding terraform resource.
+
+    ```
+    <% iam_policy_attachments.each do |policy_attachment| -%>
+    resource "aws_iam_policy_attachment" "<%= module_name_of(policy_attachment) %>" {
+        name       = "<%= policy_attachment[:name] %>"
+        policy_arn = "<%= policy_attachment[:arn] %>"
+        groups     = <%= policy_attachment[:entities].policy_groups.map(&:group_name).inspect %>
+        users      = <%= policy_attachment[:entities].policy_users.map(&:user_name).inspect %>
+        roles      = <%= policy_attachment[:entities].policy_roles.map(&:role_name).inspect %>
+    }
+
+    <% end -%>
+    ```
+
+4. `spec/lib/practice_terraforming/resource/iam_policy_attachment_spec.rb`: Change Aws client and write test for tf and tfstate
+
+    Test Perspective:
+    1. Create aws sdk result using stub.
+    2. Use the module to generate tf/tfstate.
+    3. Compare expected one and generated one.
+    ```
+    irb(main):007:0> client.list_policies.policies[0]
+    => #<struct Aws::IAM::Types::Policy policy_name="test-policy", policy_id="ABCDEFG", arn="arn:aws:iam::123456789:policy/test-policy", path="/", default_version_id="v1", attachment_count=1, permissions_boundary_usage_count=0, is_attachable=true, description=nil, create_date=2019-01-01 00:00:00 UTC, update_date=2019-01-02 00:00:00 UTC>
+client.list_entities_for_policy(policy_arn: "arn:aws:iam::351540792571:policy/ai-suggest-batch-user-policy")
+    irb(main):008:0> client.list_entities_for_policy(policy_arn: "arn:aws:iam::123456789:policy/test-policy")
+    => #<struct Aws::IAM::Types::ListEntitiesForPolicyResponse policy_groups=[#<struct Aws::IAM::Types::PolicyGroup group_name="test-group", group_id="ABCDEFG">], policy_users=[], policy_roles=[], is_truncated=false, marker=nil>
+    ```
+
+    ```
+    let(:policies) do
+       [
+          {
+            policy_name: "test-policy",
+            policy_id: "ABCDEFG",
+            arn: "arn:aws:iam::123456789:policy/test-policy",
+            path: "/",
+            default_version_id: "v1",
+            attachment_count: 1,
+            is_attachable: true,
+            create_date: Time.parse("2019-01-01 00:00:00 UTC"),
+            update_date: Time.parse("2019-01-02 00:00:00 UTC"),
+            description: nil,
+          }
+        ]
+    end
+
+    let(:entities_for_policy) do
+      {
+        policy_groups: [
+          { group_name: "test-group",  group_id: "ABCDEFG" },
+        ],
+        policy_users: [],
+        policy_roles: [],
+      }
+    end
+
+    before do
+      client.stub_responses(:list_policies, policies: policies)
+      client.stub_responses(:list_entities_for_policy, [entities_for_policy])
+    end
+    ```
+
+## Install on local
+
+### Build
+
+```
+gem build practice_terraforming.gemspec
+```
+
+the above command will generate the `practice_terraforming-X.X.X.gem`
+
+### Install
+
+0.1.0 as an example
+
+```
+gem install practice_terraforming-0.1.0.gem
+Successfully installed practice_terraforming-0.1.0
+Parsing documentation for practice_terraforming-0.1.0
+Installing ri documentation for practice_terraforming-0.1.0
+Done installing documentation for practice_terraforming after 0 seconds
+1 gem installed
+```
+
+### Check
+
+```
+practice_terraforming
+Commands:
+  practice_terraforming help [COMMAND]  # Describe available commands or one specific command
+  practice_terraforming iamr            # Iam Role
+  practice_terraforming s3              # S3
+
+Options:
+  [--merge=MERGE]                                # tfstate file to merge
+  [--overwrite], [--no-overwrite]                # Overwrite existing tfstate
+  [--tfstate], [--no-tfstate]                    # Generate tfstate
+  [--profile=PROFILE]                            # AWS credentials profile
+  [--region=REGION]                              # AWS region
+  [--assume=ASSUME]                              # Role ARN to assume
+  [--use-bundled-cert], [--no-use-bundled-cert]  # Use the bundled CA certificate from AWS SDK
+```

bin/practice_terraforming

@@ -0,0 +1,6 @@
+#!/usr/bin/env ruby
+# frozen_string_literal: true
+
+require "practice_terraforming"
+
+PracticeTerraforming::CLI.start(ARGV)

lib/practice_terraforming.rb

@@ -1,7 +1,15 @@
 # frozen_string_literal: true
 
+require "aws-sdk-iam"
+require "aws-sdk-s3"
+require "multi_json"
+require "thor"
+require "erb"
+
+require "practice_terraforming/util"
 require 'practice_terraforming/version'
 
-module PracticeTerraforming
-  # Your code goes here...
-end
+require "practice_terraforming/cli"
+require "practice_terraforming/resource/iam_role"
+require "practice_terraforming/resource/iam_policy_attachment"
+require "practice_terraforming/resource/s3"