Adding support for cloudwatch log groups

.ruby-version

@@ -0,0 +1 @@
+2.4.1

HOWTO.md

@@ -0,0 +1,57 @@
+# Terraforming How-to Contribute
+
+## Install `rvm`
+```sh
+gpg --keyserver hkp://pool.sks-keyservers.net --recv-keys 409B6B1796C275462A1703113804BB82D39DC0E3 7D2BAF1CF37B13E2069D6956105BD0E739499BDB
+sudo gpg --keyserver hkp://pool.sks-keyservers.net --recv-keys 409B6B1796C275462A1703113804BB82D39DC0E3 7D2BAF1CF37B13E2069D6956105BD0E739499BDB
+sudo apt-get install software-properties-common
+sudo apt-add-repository -y ppa:rael-gc/rvm
+sudo apt-get update
+sudo apt-get install rvm
+sudo usermod -a -G rvm yourusername
+sudo reboot
+```
+
+## Install debug tools
+```sh
+gem install pry
+gem install yaml
+gem install rdoc
+```
+
+## Install ruby build tools and docs
+```sh
+brew upgrade                        # default gcc was v5 need > 7
+sudo apt-get install rbenv          # helpful in addition to rvm
+sudo apt-get install ruby-dev       # needed for gem installers
+sudo rvm install 2.4.1              # might not be needed, I can't remember
+rvm docs generate                   # install docs
+rvm docs generate-ri                # install ri compatible docs
+```
+
+## To create new modules for `terraforming`
+```sh
+brew unlink ruby                    # only needed if ruby was installed with homebrew
+rbenv global 2.4.1                  # install Ruby v2.4.1 for entire system
+rvm use ruby-2.4.10                 # use ruby v2.4.10
+cd terraforming && script/setup     # install everything needed to contribute to terraforming
+
+# make your stuff
+rake -t                             # shows what rake tasks there are
+rake                                # runs default rake tasks
+rake spec                           # runs RSpec tests
+rake build                          # builds new version
+rake install                        # installs new version to system
+```
+
+## To debug your stuff
+```sh
+require "pry"                       # includes the pry debug library
+
+# in your code where you want a breakpoint add:
+binding.pry
+
+# helpful commands
+puts whatever.methods.to_yaml       # like pprint in python (sort of)
+help                                # will reference ri documentation
+``

README.md

@@ -10,18 +10,20 @@
 
 Export existing AWS resources to [Terraform](https://terraform.io/) style (tf, tfstate)
 
-- [Supported version](#supported-version)
-- [Installation](#installation)
-- [Prerequisites](#prerequisites)
-- [Usage](#usage)
-  -  [Export tf](#export-tf)
-  -  [Export tfstate](#export-tfstate)
-    -  [Example: Export all](#example-export-all)
-- [Run as Docker container](#run-as-docker-container-)
-- [Development](#development)
-- [Contributing](#contributing)
-- [Similar projects](#similar-projects)
-- [License](#license)
+- [Terraforming](#terraforming)
+  - [Supported version](#supported-version)
+  - [Installation](#installation)
+  - [Prerequisites](#prerequisites)
+  - [Usage](#usage)
+    - [Export tf](#export-tf)
+    - [Export tfstate](#export-tfstate)
+      - [Example: Export all](#example-export-all)
+    - [Caveats](#caveats)
+  - [Run as Docker container ![Docker Repository on Quay.io](https://quay.io/repository/dtan4/terraforming)](#run-as-docker-container-)
+  - [Development](#development)
+  - [Contributing](#contributing)
+  - [Similar projects](#similar-projects)
+  - [License](#license)
 
 ## Supported version
 
@@ -87,6 +89,7 @@ Commands:
   terraforming alb             # ALB
   terraforming asg             # AutoScaling Group
   terraforming cwa             # CloudWatch Alarm
+  terraforming cwlg            # CloudWatch Log Group
   terraforming dbpg            # Database Parameter Group
   terraforming dbsg            # Database Security Group
   terraforming dbsn            # Database Subnet Group

lib/terraforming.rb

@@ -1,5 +1,6 @@
 require "aws-sdk-autoscaling"
 require "aws-sdk-cloudwatch"
+require "aws-sdk-cloudwatchlogs"
 require "aws-sdk-dynamodb"
 require "aws-sdk-ec2"
 require "aws-sdk-efs"
@@ -27,6 +28,7 @@
 require "terraforming/resource/alb"
 require "terraforming/resource/auto_scaling_group"
 require "terraforming/resource/cloud_watch_alarm"
+require "terraforming/resource/cloud_watch_log_group"
 require "terraforming/resource/db_parameter_group"
 require "terraforming/resource/db_security_group"
 require "terraforming/resource/db_subnet_group"

lib/terraforming/cli.rb

@@ -25,6 +25,11 @@ def cwa
       execute(Terraforming::Resource::CloudWatchAlarm, options)
     end
 
+    desc "cwlg", "CloudWatch Log Group"
+    def cwlg
+      execute(Terraforming::Resource::CloudWatchLogGroup, options)
+    end
+
     desc "dbpg", "Database Parameter Group"
     def dbpg
       execute(Terraforming::Resource::DBParameterGroup, options)

lib/terraforming/resource/cloud_watch_log_group.rb

@@ -0,0 +1,56 @@
+module Terraforming
+  module Resource
+    class CloudWatchLogGroup
+      include Terraforming::Util
+
+      def self.tf(client: Aws::CloudWatchLogs::Client.new)
+        self.new(client).tf
+      end
+
+      def self.tfstate(client: Aws::CloudWatchLogs::Client.new)
+        self.new(client).tfstate
+      end
+
+      def initialize(client)
+        @client = client
+      end
+
+      def tf
+        apply_template(@client, "tf/cloud_watch_log_group")
+      end
+
+      def tfstate
+        log_groups.inject({}) do |resources, log_group|
+          attributes = {
+            "arn"                 => log_group["arn"].to_s,
+            "creation_time"       => log_group["creation_time"].to_i,
+            "kms_key_id"          => log_group["kms_key_id"].to_s,
+            "log_group_name"      => log_group["log_group_name"].to_s,
+            "metric_filter_count" => log_group["metric_filter_count"].to_i,
+            "retention_in_days"   => log_group["retention_in_days"].to_i,
+            "stored_bytes"        => log_group["stored_bytes"].to_i
+          }
+
+          resources["aws_cloudwatch_log_group.#{module_name_of(log_group)}"] = {
+            "type" => "aws_cloudwatch_log_group",
+            "primary" => {
+              "id" => log_group.log_group_name,
+              "attributes" => attributes
+            }
+          }
+        end
+      end
+
+      private
+
+      def log_groups
+        @client.describe_log_groups.map(&:log_groups).flatten
+      end
+
+      def module_name_of(log_group)
+        normalize_module_name(log_group.log_group_name)
+      end    
+
+    end
+  end
+end

lib/terraforming/template/tf/cloud_watch_log_group.erb

@@ -0,0 +1,7 @@
+<% log_groups.each do |log_group| -%>
+resource "aws_cloudwatch_log_group" "<%= normalize_module_name(log_group.log_group_name) %>" {
+    name                = "<%= log_group.log_group_name %>"
+    retention_in_days   = "<%= log_group.retention_in_days %>"
+    kms_key_id          = "<%= log_group.kms_key_id %>"
+}
+<% end -%>

spec/lib/terraforming/cli_spec.rb

@@ -64,6 +64,13 @@ module Terraforming
         it_behaves_like "CLI examples"
       end
 
+      describe "cwlg" do
+        let(:klass)   { Terraforming::Resource::CloudWatchLogGroup }
+        let(:command) { :cwlg }
+
+        it_behaves_like "CLI examples"
+      end
+
       describe "dbpg" do
         let(:klass)   { Terraforming::Resource::DBParameterGroup }
         let(:command) { :dbpg }

spec/lib/terraforming/resource/cloud_watch_log_group_spec.rb

@@ -0,0 +1,63 @@
+require "spec_helper"
+
+module Terraforming
+  module Resource
+    describe CloudWatchLogGroup do
+      let(:client) do
+        Aws::CloudWatchLogs::Client.new(stub_responses: true)
+      end
+
+      let(:log_groups) do
+        [
+          {
+            arn: "arn:aws:logs:region:account:log-group",
+            creation_time: 1596223046916,
+            kms_key_id: "fbe14984-fd9f-40d2-94ce-55d738d35daa",
+            log_group_name: "Dummy Log Group 1",
+            metric_filter_count: 0,
+            retention_in_days: 90,
+            stored_bytes: 227
+          }
+        ]
+      end
+
+    before do
+      client.stub_responses(:describe_log_groups, log_groups: log_groups)
+    end
+
+      describe ".tf" do
+        it "should generate tf" do
+          expect(described_class.tf(client: client)).to eq <<-EOS
+resource "aws_cloudwatch_log_group" "Dummy-Log-Group-1" {
+    name                = "Dummy Log Group 1"
+    retention_in_days   = "90"
+    kms_key_id          = "fbe14984-fd9f-40d2-94ce-55d738d35daa"
+}
+          EOS
+        end
+      end
+
+      describe ".tfstate" do
+        it "should generate tfstate" do
+          expect(described_class.tfstate(client: client)).to eq(
+            {
+              "primary" => {
+                "attributes" => {
+                  "arn"                 => "arn:aws:logs:region:account:log-group",
+                  "creation_time"       => 1596223046916,
+                  "kms_key_id"          => "fbe14984-fd9f-40d2-94ce-55d738d35daa",
+                  "log_group_name"      => "Dummy Log Group 1",
+                  "metric_filter_count" => 0,
+                  "retention_in_days"   => 90,
+                  "stored_bytes"        => 227
+                },
+                "id" => "Dummy Log Group 1"
+              },
+              "type" => "aws_cloudwatch_log_group"
+            }
+          )
+        end
+      end
+    end
+  end
+end

terraforming.gemspec

@@ -21,6 +21,7 @@ Gem::Specification.new do |spec|
 
   spec.add_dependency "aws-sdk-autoscaling", "~> 1"
   spec.add_dependency "aws-sdk-cloudwatch", "~> 1"
+  spec.add_dependency "aws-sdk-cloudwatchlogs", "~> 1"
   spec.add_dependency "aws-sdk-dynamodb", "~> 1.18"
   spec.add_dependency "aws-sdk-ec2", "~> 1"
   spec.add_dependency "aws-sdk-efs", "~> 1", ">= 1.13.0"