Merge pull request #9 from collectiveidea/active-support-notifications

Instrument with ActiveSupport::Notifications

.github/workflows/ci.yml

@@ -14,8 +14,10 @@ jobs:
     strategy:
       matrix:
         ruby:
-          - '3.1.3'
-          - '3.2.0'
+          - 2.7
+          - '3.0' # keep as string or it turns into "3" which pulls the newest 3.x, not 3.0.x
+          - 3.1
+          - 3.2
 
     env:
       RUBYOPT: --enable=frozen-string-literal

.standard.yml

@@ -1,3 +1,6 @@
 # For available configuration options, see:
 #   https://github.com/testdouble/standard
-ruby_version: 2.6
+ruby_version: 2.7
+plugins:
+  - standard-performance
+  - standard-rails

Gemfile

@@ -5,9 +5,11 @@ source "https://rubygems.org"
 # Specify your gem's dependencies in twirp-rails.gemspec
 gemspec
 
-gem "rake", "~> 13.0"
+gem "rake"
 
 gem "debug"
-gem "rspec-rails", "~> 3.0"
+gem "rspec-rails"
 gem "sqlite3"
-gem "standard", "~> 1.3"
+gem "standard"
+gem "standard-performance"
+gem "standard-rails"

lib/twirp/rails.rb

@@ -10,6 +10,7 @@ class Error < StandardError; end
 end
 
 require "twirp"
+require "active_support/notifications"
 require_relative "rails/callbacks"
 require_relative "rails/configuration"
 require_relative "rails/dispatcher"

lib/twirp/rails/callbacks.rb

@@ -40,6 +40,7 @@ module Callbacks
           terminator: ->(controller, result_lambda) {
             # save off the error and terminate if a callback returns a Twirp::Error
             result = result_lambda.call
+
             if result.is_a?(Twirp::Error)
               controller.error = result
               true

lib/twirp/rails/handler.rb

@@ -31,8 +31,12 @@ def process(name, request, env)
       # Notice that the first argument is the method to be dispatched
       # which is *not* necessarily the same as the action name.
       def process_action(name)
-        run_callbacks(:process_action) do
-          send_action(name)
+        ActiveSupport::Notifications.instrument("handler_run_callbacks.twirp_rails", handler: self.class.name, action: action_name, env: @env, request: @request) do
+          run_callbacks(:process_action) do
+            ActiveSupport::Notifications.instrument("handler_run.twirp_rails", handler: self.class.name, action: action_name, env: @env, request: @request) do |payload|
+              payload[:response] = send_action(name)
+            end
+          end
         end
       end
 

spec/rails_app/app/handlers/haberdasher_handler.rb

@@ -1,4 +1,8 @@
+require "ip_tracker"
 class HaberdasherHandler < Twirp::Rails::Handler
+  before_action :track_request_ip
+  before_action :reject_giant_hats
+
   def make_hat
     # We can return a Twirp::Error when appropriate
     if request.inches < 12
@@ -12,4 +16,19 @@ def make_hat
       color: "Tan"
     )
   end
+
+  private
+
+  # Contrived example of using a before_action with data that
+  # comes from a :before service hook.
+  def track_request_ip
+    IPTracker.track(env[:ip])
+  end
+
+  # contrived example of using a before_action
+  def reject_giant_hats
+    if request.inches >= 1_000
+      Twirp::Error.invalid_argument("is too big", argument: "inches")
+    end
+  end
 end

spec/rails_app/config/application.rb

@@ -8,6 +8,5 @@
 module RailsApp
   class Application < Rails::Application
     config.root = File.expand_path("../../", __FILE__)
-    config.active_record.legacy_connection_handling = false
   end
 end

spec/rails_app/config/initializers/twirp_rails.rb

@@ -0,0 +1,8 @@
+Rails.application.config.twirp.service_hooks[:before] = lambda do |rack_env, env|
+  # Make IP accessible to the handlers
+  env[:ip] = rack_env["REMOTE_ADDR"]
+end
+
+Rails.application.config.twirp.middleware = [
+  Rack::Deflater
+]

spec/rails_app/lib/ip_tracker.rb

@@ -0,0 +1,6 @@
+# Realistic-looking class/model we'll interact with for testing.
+class IPTracker
+  def self.track(ip)
+    @ip = ip
+  end
+end

spec/requests/haberdasher_spec.rb

@@ -1,7 +1,7 @@
 require "spec_helper"
 
 RSpec.describe "Haberdasher Service", type: :request do
-  it "makes a hat" do
+  def make_hat_success_request
     size = Twirp::Example::Haberdasher::Size.new(inches: 24)
 
     post "/twirp/twirp.example.haberdasher.Haberdasher/MakeHat",
@@ -10,6 +10,12 @@
         "Content-Type" => "application/protobuf"
       }
     expect(response).to be_successful
+    decoded = Twirp::Example::Haberdasher::Hat.decode(response.body)
+    expect(decoded).to be_a(Twirp::Example::Haberdasher::Hat)
+  end
+
+  it "makes a hat" do
+    make_hat_success_request
   end
 
   describe "error handling" do
@@ -26,5 +32,92 @@
       expect(response.content_type).to eq("application/json")
       expect(response.body).to eq('{"code":"invalid_argument","msg":"is too small","meta":{"argument":"inches"}}')
     end
+
+    it "allows a before_action to return a Twirp::Error" do
+      size = Twirp::Example::Haberdasher::Size.new(inches: 12_000)
+
+      post "/twirp/twirp.example.haberdasher.Haberdasher/MakeHat",
+        params: size.to_proto, headers: {
+          :accept => "application/protobuf",
+          "Content-Type" => "application/protobuf"
+        }
+
+      expect(response.status).to eq(400)
+      expect(response.content_type).to eq("application/json")
+      expect(response.body).to eq('{"code":"invalid_argument","msg":"is too big","meta":{"argument":"inches"}}')
+    end
+  end
+
+  describe "notifications" do
+    before do
+      @events = []
+      @subscriber = ActiveSupport::Notifications.subscribe(/twirp_rails/) do |*args|
+        @events << ActiveSupport::Notifications::Event.new(*args)
+      end
+    end
+
+    after do
+      ActiveSupport::Notifications.unsubscribe(@subscriber)
+    end
+
+    it "publishes ActiveSupport::Notifications for the handler" do
+      make_hat_success_request
+
+      expect(@events).to contain_exactly(
+        have_attributes(name: "handler_run.twirp_rails",
+          payload: {
+            handler: "HaberdasherHandler",
+            action: "make_hat",
+            env: an_instance_of(Hash),
+            request: an_instance_of(Twirp::Example::Haberdasher::Size),
+            response: an_instance_of(Twirp::Example::Haberdasher::Hat)
+          }),
+        have_attributes(name: "handler_run_callbacks.twirp_rails",
+          payload: {
+            handler: "HaberdasherHandler",
+            action: "make_hat",
+            env: an_instance_of(Hash),
+            request: an_instance_of(Twirp::Example::Haberdasher::Size)
+          })
+      )
+
+      # In order that events were initialized
+      expect(@events.sort_by(&:time).map(&:name)).to contain_exactly("handler_run.twirp_rails", "handler_run_callbacks.twirp_rails")
+    end
+  end
+
+  describe "service hooks" do
+    it "can inject data via a before hook" do
+      expect(IPTracker).to receive(:track).with("127.0.0.1")
+      make_hat_success_request
+    end
+  end
+
+  describe "middleware" do
+    it "runs injected middleware when appropriate" do
+      size = Twirp::Example::Haberdasher::Size.new(inches: 24)
+
+      post "/twirp/twirp.example.haberdasher.Haberdasher/MakeHat",
+        params: size.to_proto, headers: {
+          :accept => "application/protobuf",
+          "Content-Type" => "application/protobuf",
+          "Accept-Encoding" => "gzip" # ask for GZIP encoding
+        }
+      expect(response.headers["Vary"]).to eq("Accept-Encoding")
+      expect(response.headers["Content-Encoding"]).to eq("gzip")
+    end
+
+    it "ignores injected middleware when inappropriate" do
+      size = Twirp::Example::Haberdasher::Size.new(inches: 24)
+
+      post "/twirp/twirp.example.haberdasher.Haberdasher/MakeHat",
+        params: size.to_proto, headers: {
+          :accept => "application/protobuf",
+          "Content-Type" => "application/protobuf"
+          # no encoding specified
+        }
+      expect(response.headers["Vary"]).to eq("Accept-Encoding")
+      expect(response.headers["Content-Encoding"]).to be_nil
+    end
   end
 end

twirp-rails.gemspec

@@ -12,7 +12,7 @@ Gem::Specification.new do |spec|
   spec.description = "A simple way to serve Twirp RPC services in a Rails app. Minimial configuration and familiar Rails conventions."
   spec.homepage = "https://github.com/collectiveidea/twirp-rails"
   spec.license = "MIT"
-  spec.required_ruby_version = ">= 2.6.0"
+  spec.required_ruby_version = ">= 2.7.0"
 
   spec.metadata["homepage_uri"] = spec.homepage
   spec.metadata["source_code_uri"] = "https://github.com/collectiveidea/twirp-rails"