From 8fb8bcf726fb99ca63a4e3eefe07652d4ad01f0e Mon Sep 17 00:00:00 2001
From: Aotokitsuruya <contact@aotoki.me>
Date: Mon, 1 Jan 2024 16:09:29 +0800
Subject: [PATCH] Add Rack handler

---
 .github/workflows/main.yml       | 38 ++++++++++++++++++++-----
 lib/hanami/lambda.rb             | 35 +++++++++++++++++++++++
 lib/hanami/lambda/application.rb | 37 ++++++++++++++++++++++++
 lib/hanami/lambda/rack.rb        | 49 ++++++++++++++++++++++++++++++++
 4 files changed, 152 insertions(+), 7 deletions(-)
 create mode 100644 lib/hanami/lambda/application.rb
 create mode 100644 lib/hanami/lambda/rack.rb

diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 37a9318..d85aab6 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -1,21 +1,45 @@
-name: Ruby
+name: CI
 
 on:
   push:
+    paths:
+      - '.github/workflows/ci.yml'
+      - 'lib/**'
+      - '*.gemspec'
+      - 'spec/**'
+      - 'Rakefile'
+      - 'Gemfile'
+      - '.rubocop.yml'
+  pull_request:
     branches:
       - main
-
-  pull_request:
+  schedule:
+    - cron: '30 4 * * *'
+  create:
 
 jobs:
-  build:
+  rubocop:
+    runs-on: ubuntu-latest
+    name: Rubocop
+    steps:
+    - uses: actions/checkout@v4
+    - name: Set up Ruby
+      uses: ruby/setup-ruby@v1
+      with:
+        ruby-version: '3.2'
+        bundler-cache: true
+    - name: Run linter
+      run: bundle exec rake rubocop
+
+  tests:
     runs-on: ubuntu-latest
     name: Ruby ${{ matrix.ruby }}
     strategy:
       matrix:
         ruby:
-          - '3.3.0'
-
+          - '3.2'
+          - '3.1'
+          - '3.0'
     steps:
     - uses: actions/checkout@v4
     - name: Set up Ruby
@@ -23,5 +47,5 @@ jobs:
       with:
         ruby-version: ${{ matrix.ruby }}
         bundler-cache: true
-    - name: Run the default task
+    - name: Run all tests
       run: bundle exec rake
diff --git a/lib/hanami/lambda.rb b/lib/hanami/lambda.rb
index c75ea76..1eb358f 100644
--- a/lib/hanami/lambda.rb
+++ b/lib/hanami/lambda.rb
@@ -11,6 +11,41 @@ module Hanami
   # @since 0.1.0
   # @api private
   module Lambda
+    @_mutex = Mutex.new
+
+    # Returns the Hanami::Lambda application.
+    #
+    # @return [Hanami::Lambda::Application] the application
+    # @raise [Hanami::AppLoadError] if the application isn't configured
+    #
+    # @api public
+    # @since 0.1.0
+    def app
+      @_mutex.synchronize do
+        unless defined?(@_app)
+          raise Hanami::AppLoadError,
+                "Hanami::Lambda.app is not yet configured. "
+        end
+
+        @_app
+      end
+    end
+
+    # @api private
+    # @since 0.1.0
+    def app=(klass)
+      @_mutex.synchronize do
+        raise AppLoadError, "Hanami::Lambda.app is already configured." if instance_variable_defined?(:@_app)
+
+        @_app = klass unless klass.name.nil?
+      end
+    end
+
+    def call(event:, context:)
+      Hanami.boot
+      app.call(event: event, context: context)
+    end
+
     # @since 0.1.0
     # @api private
     def self.gem_loader
diff --git a/lib/hanami/lambda/application.rb b/lib/hanami/lambda/application.rb
new file mode 100644
index 0000000..593f6ef
--- /dev/null
+++ b/lib/hanami/lambda/application.rb
@@ -0,0 +1,37 @@
+# frozen_string_literal: true
+
+module Hanami
+  module Lambda
+    # The application to configure for AWS Lambda.
+    #
+    # @since 0.1.0
+    class Application
+      # @api private
+      def self.inherited(subclass)
+        super
+
+        Hanami::Lambda.app = subclass
+        subclass.extend(ClassMethods)
+      end
+
+      module ClassMethods
+        # Dispatch event to the handler
+        #
+        # @api private
+        # @since 0.1.0
+        def call(event:, context:)
+          handler = lookup(event: event, context: context)
+          handler.call
+        end
+
+        # Lookup the handler for the given event
+        #
+        # @api private
+        # @since 0.1.0
+        def lookup(event:, context:)
+          Rack.new(Hanami.app, event: event, context: context)
+        end
+      end
+    end
+  end
+end
diff --git a/lib/hanami/lambda/rack.rb b/lib/hanami/lambda/rack.rb
new file mode 100644
index 0000000..19a7a87
--- /dev/null
+++ b/lib/hanami/lambda/rack.rb
@@ -0,0 +1,49 @@
+# frozen_string_literal: true
+
+module Hanami
+  module Lambda
+    # Rack interface for AWS Lambda.
+    #
+    # @api private
+    # @since 0.1.0
+    class Rack
+      attr_reader :app, :event, :context
+
+      # @api private
+      def initialize(app, event:, context:)
+        @app = app
+        @event = event
+        @context = context
+      end
+
+      # Handle the request
+      #
+      # @return [Hash] the response
+      #
+      # @since 0.1.0
+      def call
+        status_code, headers, body = app.call(env)
+
+        {
+          statusCode: status_code,
+          headers: headers,
+          body: body.join
+        }
+      end
+
+      # Build the Rack environment
+      #
+      # @return [Hash] the Rack environment
+      #
+      # @since 0.1.0
+      def env
+        {
+          ::Rack::REQUEST_METHOD => event["httpMethod"],
+          ::Rack::PATH_INFO => event["path"] || "",
+          ::Rack::VERSION => ::Rack::VERSION,
+          ::Rack::RACK_INPUT => StringIO.new(event["body"] || "")
+        }
+      end
+    end
+  end
+end