Move to use rate_throttle_client Gem

Instead of maintaining a single purpose rate throttle client wrapper, I ported the code over to a gem `rate_throttle_client` that has it's own set of tests and metrics generating code. This will make it easier to maintain and other libraries can use the code now as well.

I'm now also testing configuring the rate throttling logic.

README.md

@@ -314,15 +314,26 @@ By default client requests from this library will respect Heroku's rate-limiting
 
 Once a single request has been rate-limited, the client will auto-tune a sleep value so that future requests are less likely to be rate-limited by the server.
 
-To disable this retry and sleep behavior set the env var`PLATFORM_API_DISABLE_RATE_THROTTLE=1`.
+Rate throttle strategies are provided by [the Rate Throttle Client gem](https://github.com/zombocom/rate_throttle_client). By default the `RateThrottleClient::ExponentialIncreaseProportionalRemainingDecrease` strategy is used.
 
-For more information about this algorithm and behavior see [Rate Limit GCRA client demo](https://github.com/schneems/rate-limit-gcra-client-demo).
+To disable this retry-and-sleep behavior you can change the rate throttling strategy to any object that responds to `call` and yields to a block:
+
+```ruby
+PlatformAPI.rate_throttle = ->(&block) { block.call }
+
+# or
+
+PlatformAPI.rate_throttle = RateThrottleClient::Null.new
+```
 
 By default rate throttling will log to STDOUT when the sleep/retry behavior is triggered. To add your own custom logging, for example to librato or honeycomb, you can pass in a callable object that takes three arguments:
 
 ```ruby
-PlatformAPI.rate_throttle.log = ->(event_type, request, throttle_object) {
+PlatformAPI.rate_throttle.log = ->(info) {
   # Your logic here
+
+  puts info.sleep_for
+  puts info.request
 }
 ```
 

config/client-config.rb

@@ -1,19 +1,17 @@
 # frozen_string_literal: true
 require 'heroics'
+require 'rate_throttle_client'
+
 require File.join(File.expand_path('../..', __FILE__), 'lib', 'platform-api', 'version.rb')
-require File.join(File.expand_path('../..', __FILE__), 'lib', 'platform-api', 'heroku_client_throttle.rb')
 
 Heroics.default_configuration do |config|
   config.base_url = 'https://api.heroku.com'
   config.module_name = 'PlatformAPI'
   config.schema_filepath = File.join(File.expand_path('../..', __FILE__), 'schema.json')
 
-  unless ENV['PLATFORM_API_DISABLE_RATE_THROTTLE']
-    PlatformAPI.rate_throttle = PlatformAPI::HerokuClientThrottle.new
-
-    config.rate_throttle = PlatformAPI.rate_throttle
-    config.acceptable_status_codes = [429]
-  end
+  PlatformAPI.rate_throttle = RateThrottleClient::ExponentialIncreaseProportionalRemainingDecrease.new
+  config.rate_throttle = PlatformAPI.rate_throttle
+  config.acceptable_status_codes = [429]
 
   config.headers = {
     'Accept'      => 'application/vnd.heroku+json; version=3',

lib/platform-api.rb

@@ -5,6 +5,9 @@
 module PlatformAPI
   def self.rate_throttle=(rate_throttle)
     @rate_throttle = rate_throttle
+    Heroics.default_configuration do |config|
+      config.rate_throttle = @rate_throttle
+    end
   end
 
   # Get access to the rate throttling class object for configuration.
@@ -16,7 +19,5 @@ def self.rate_throttle
 end
 
 require_relative '../config/client-config'
-
 require 'platform-api/client'
 require 'platform-api/version'
-require 'platform-api/heroku_client_throttle'

platform-api.gemspec

@@ -30,4 +30,5 @@ Gem::Specification.new do |spec|
 
   spec.add_dependency 'heroics', '~> 0.1.1'
   spec.add_dependency 'moneta', '~> 1.0.0'
+  spec.add_dependency 'rate_throttle_client', '~> 0.1.0'
 end

spec/acceptance/config_spec.rb

@@ -0,0 +1,67 @@
+require 'platform-api'
+
+describe 'Platform API config' do
+  describe 'rate limiting' do
+    before(:each) do
+      WebMock.enable!
+
+      rate_throttle = PlatformAPI.rate_throttle
+      @original_rate_throttle = rate_throttle.dup
+
+      # No junk in test dots
+      rate_throttle.log = ->(*_) {}
+
+      # Don't sleep in tests
+      def rate_throttle.sleep(value); end
+    end
+
+    after(:each) do
+      WebMock.disable!
+
+      PlatformAPI.rate_throttle = @original_rate_throttle
+    end
+
+    it "works even if first request is rate limited" do
+      stub_request(:get, "https://api.heroku.com/apps")
+        .to_return([
+          {status: 429},
+          {status: 200}
+        ])
+
+      client.app.list
+
+      expect(WebMock).to have_requested(:get, "https://api.heroku.com/apps").twice
+    end
+
+    it "allows the rate throttling class to be modified" do
+      stub_request(:get, "https://api.heroku.com/apps")
+        .to_return([
+          {status: 429},
+          {status: 429},
+          {status: 200}
+        ])
+
+      @retry_count = 0
+      PlatformAPI.rate_throttle.log = ->(*_) { @retry_count += 1 }
+      client.app.list
+
+      expect(WebMock).to have_requested(:get, "https://api.heroku.com/apps").times(3)
+      expect(@retry_count).to eq(2)
+    end
+
+    it "allows rate throttling logic to be changed" do
+      stub_request(:get, "https://api.heroku.com/apps")
+        .to_return([
+          {status: 429}
+        ])
+
+      @times_called = 0
+      PlatformAPI.rate_throttle = ->(&block) { @times_called += 1; block.call }
+
+      client.app.list
+
+      expect(WebMock).to have_requested(:get, "https://api.heroku.com/apps").once
+      expect(@times_called).to eq(1)
+    end
+  end
+end

spec/acceptance/generated_client_spec.rb

@@ -1,30 +1,11 @@
-require 'netrc'
-require 'platform-api'
-require 'hatchet'
-require 'webmock/rspec'
-
-include WebMock::API
-WebMock.allow_net_connect!
 
 describe 'The generated platform api client' do
   before(:all) do
     @app_name = ENV["TEST_APP_NAME"] || hatchet_app.name
   end
 
-  it "works even if first request is rate limited" do
-    WebMock.enable!
-    url = "https://api.heroku.com/apps"
-    stub_request(:get, url)
-      .to_return([
-        {status: 429},
-        {status: 200}
-      ])
-
-    client.app.list
-
-    expect(WebMock).to have_requested(:get, url).twice
-  ensure
-    WebMock.disable!
+  def app_name
+    @app_name
   end
 
   it "can get account info" do
@@ -74,42 +55,4 @@
   it "can get app webhooks" do
     expect(client.app_webhook.list(app_name)).not_to be_empty
   end
-
-  def app_name
-    @app_name
-  end
-
-  def hatchet_app
-    @hatchet_app ||= begin
-      app = Hatchet::Runner.new("default_ruby", buildpacks: ["heroku/ruby"])
-      app.in_directory do
-        app.setup!
-        app.push_with_retry!
-      end
-      app.api_rate_limit.call.app_webhook.create(app.name, include: ["dyno"] , level: "notify", url: "https://example.com")
-      app.api_rate_limit.call.addon.create(app.name, plan: 'heroku-postgresql' )
-      app
-    end
-  end
-
-  def email
-    @email
-  end
-
-  def client
-    @client ||=
-      begin
-        entry = Netrc.read['api.heroku.com']
-        if entry
-          oauth_token = entry.password
-          @email = entry.login
-        else
-          oauth_token = ENV['OAUTH_TOKEN']
-          @email = ENV['ACCOUNT_EMAIL']
-        end
-        raise "Must set env vars or write a netrc" unless @email
-
-        PlatformAPI.connect_oauth(oauth_token)
-      end
-  end
 end

spec/spec_helper.rb

@@ -1,4 +1,12 @@
 require 'pry'
+require 'webmock/rspec'
+require 'platform-api'
+require 'netrc'
+require 'hatchet'
+
+include WebMock::API
+WebMock.allow_net_connect!
+
 RSpec.configure do |config|
   config.expect_with :rspec do |expectations|
     expectations.include_chain_clauses_in_custom_matcher_descriptions = true
@@ -18,3 +26,32 @@
   config.order = :random
   Kernel.srand config.seed
 end
+
+def hatchet_app
+  @hatchet_app ||= begin
+    app = Hatchet::Runner.new("default_ruby", buildpacks: ["heroku/ruby"])
+    app.in_directory do
+      app.setup!
+      app.push_with_retry!
+    end
+    app.api_rate_limit.call.app_webhook.create(app.name, include: ["dyno"] , level: "notify", url: "https://example.com")
+    app.api_rate_limit.call.addon.create(app.name, plan: 'heroku-postgresql' )
+    app
+  end
+end
+
+def client
+  @client ||= begin
+    entry = Netrc.read['api.heroku.com']
+    if entry
+      oauth_token = entry.password
+      @email = entry.login
+    else
+      oauth_token = ENV['OAUTH_TOKEN']
+      @email = ENV['ACCOUNT_EMAIL']
+    end
+    raise "Must set env vars or write a netrc" unless @email
+
+    PlatformAPI.connect_oauth(oauth_token)
+  end
+end