[ENG-125] Add support for retries with exponential backoff for rate limit errors (#7)

* chore: bump gem version to 1.3.0

* feat: add new configuration fields for retries with backoff

* feat: add method to automatically retry failed requests

The API call block will be called in a method that checks if the
request failed or not. If the response status code falls in one of the
configured status, it will make retries with exponential backoff.

Author: jrebocho

.travis.yml

@@ -8,4 +8,4 @@ script:
   - bundle install --path vendor/bundle
   - bundle exec rspec
   - gem build stackone_hris_client.gemspec
-  - gem install ./stackone_hris_client-1.2.2.gem
+  - gem install ./stackone_hris_client-1.3.0.gem

Gemfile.lock

@@ -1,7 +1,7 @@
 PATH
   remote: .
   specs:
-    stackone_hris_client (1.2.2)
+    stackone_hris_client (1.3.0)
       typhoeus (~> 1.0, >= 1.0.1)
 
 GEM

README.md

@@ -7,7 +7,7 @@ The documentation for the StackOne Unified API - HRIS
 This SDK is automatically generated by the [OpenAPI Generator](https://openapi-generator.tech) project:
 
 - API version: 1.0.0
-- Package version: 1.2.2
+- Package version: 1.3.0
 - Build package: org.openapitools.codegen.languages.RubyClientCodegen
 
 ## Installation
@@ -23,16 +23,16 @@ gem build stackone_hris_client.gemspec
 Then either install the gem locally:
 
 ```shell
-gem install ./stackone_hris_client-1.2.2.gem
+gem install ./stackone_hris_client-1.3.0.gem
 ```
 
-(for development, run `gem install --dev ./stackone_hris_client-1.2.2.gem` to install the development dependencies)
+(for development, run `gem install --dev ./stackone_hris_client-1.3.0.gem` to install the development dependencies)
 
 or publish the gem to a gem hosting service, e.g. [RubyGems](https://rubygems.org/).
 
 Finally add this to the Gemfile:
 
-    gem 'stackone_hris_client', '~> 1.2.2'
+    gem 'stackone_hris_client', '~> 1.3.0'
 
 ### Install from Git
 

gem-config.yml

@@ -10,5 +10,5 @@ additionalProperties:
   gemName: "stackone_hris_client"
   gemRequiredRubyVersion: ">= 2.7"
   gemSummary: "StackOne HRIS client gem"
-  gemVersion: "1.2.2"
+  gemVersion: "1.3.0"
   library: "typhoeus"

lib/stackone_hris_client/api_client.rb

@@ -46,7 +46,7 @@ def self.default
     #
     # @return [Array<(Object, Integer, Hash)>] an array of 3 elements:
     #   the data deserialized from response body (could be nil), response status code and response headers.
-    def call_api(http_method, path, opts = {})
+    def call_api_basic(http_method, path, opts = {})
       request = build_request(http_method, path, opts)
       response = request.run
 
@@ -77,6 +77,12 @@ def call_api(http_method, path, opts = {})
       return data, response.code, response.headers
     end
 
+    def call_api(http_method, path, opts = {})
+      retries_errors_with_exponential_backoff do
+        return call_api_basic(http_method, path, opts)
+      end
+    end
+
     # Builds the HTTP request
     #
     # @param [String] http_method HTTP method/verb (e.g. POST)
@@ -158,6 +164,41 @@ def build_request_body(header_params, form_params, body)
       data
     end
 
+    def retries_errors_with_exponential_backoff(
+      max_retries: @config.max_retries,
+      initial_backoff_seconds: @config.initial_backoff_seconds,
+      max_backoff_seconds: @config.max_backoff_seconds,
+      &block
+    )
+      retry_count = 0
+      backoff_seconds = initial_backoff_seconds
+
+      loop do
+        begin
+          yield
+          break
+        rescue ApiError => e
+          raise e unless @config.retry_status_codes.include? e.code
+
+          if @config.debugging
+            @config.logger.debug "The error code (#{e.code}) matches retry_status_codes list. Retrying #(#{retry_count}) in #{backoff_seconds}s..."
+          end
+
+          if retry_count >= max_retries
+            if @config.debugging
+              @config.logger.debug "Maximum number of retries (#{max_retries}) reached. Raising exception: #{e}"
+            end
+
+            raise e
+          else
+            sleep backoff_seconds
+            retry_count += 1
+            backoff_seconds = [backoff_seconds * 2, max_backoff_seconds].min
+          end
+        end
+      end
+    end
+
     # Save response body into a file in (the defined) temporary folder, using the filename
     # from the "Content-Disposition" header if provided, otherwise a random filename.
     # The response body is written to the file in chunks in order to handle files which

lib/stackone_hris_client/configuration.rb

@@ -152,6 +152,18 @@ class Configuration
 
     attr_accessor :force_ending_format
 
+    # Set this to customize the number of times to retry an API call when a server error occurs.
+    attr_accessor :max_retries
+
+    # Set this to customize the initial number of seconds to wait before retrying an API call when a server error occurs.
+    attr_accessor :initial_backoff_seconds
+
+    # Set this to customize the maximum number of seconds to keep retrying an API call when a server error occurs.
+    attr_accessor :max_backoff_seconds
+
+    # Define the status codes that should be retried.
+    attr_accessor :retry_status_codes
+
     def initialize
       @scheme = 'https'
       @host = 'stackone.com'
@@ -173,6 +185,12 @@ def initialize
       @debugging = false
       @inject_format = false
       @force_ending_format = false
+
+      @max_retries = 5
+      @initial_backoff_seconds = 1
+      @max_backoff_seconds = 60
+      @retry_status_codes = [429]
+
       @logger = defined?(Rails) ? Rails.logger : Logger.new(STDOUT)
 
       yield(self) if block_given?

lib/stackone_hris_client/version.rb

@@ -11,5 +11,5 @@
 =end
 
 module StackOneHRIS
-  VERSION = '1.2.2'
+  VERSION = '1.3.0'
 end