Improve maintainability of labeler class using polymorphism

common/lib/dependabot/pull_request_creator.rb

@@ -12,6 +12,7 @@ class PullRequestCreator
     require "dependabot/pull_request_creator/message_builder"
     require "dependabot/pull_request_creator/branch_namer"
     require "dependabot/pull_request_creator/labeler"
+    require "dependabot/pull_request_creator/labelers/factory"
 
     class RepoNotFound < StandardError; end
 
@@ -225,7 +226,7 @@ def branch_namer
 
     def labeler
       @labeler ||=
-        Labeler.new(
+        Dependabot::PullRequestCreator::Labelers::Factory.for_source(
           source: source,
           custom_labels: custom_labels,
           credentials: credentials,

common/lib/dependabot/pull_request_creator/labeler.rb

@@ -2,6 +2,7 @@
 
 require "octokit"
 require "dependabot/pull_request_creator"
+
 module Dependabot
   class PullRequestCreator
     class Labeler
@@ -26,12 +27,11 @@ def register_label_details(package_manager, label_details)
         end
       end
 
-      def initialize(source:, custom_labels:, credentials:, dependencies:,
+      def initialize(source:, custom_labels:, dependencies:,
                      includes_security_fixes:, label_language:,
                      automerge_candidate:)
         @source                  = source
         @custom_labels           = custom_labels
-        @credentials             = credentials
         @dependencies            = dependencies
         @includes_security_fixes = includes_security_fixes
         @label_language          = label_language
@@ -53,29 +53,13 @@ def labels_for_pr
         ].compact.uniq
       end
 
-      def label_pull_request(pull_request_number)
-        create_default_labels_if_required
-
-        return if labels_for_pr.none?
-        raise "Only GitHub!" unless source.provider == "github"
-
-        github_client_for_source.add_labels_to_an_issue(
-          source.repo,
-          pull_request_number,
-          labels_for_pr
-        )
-      rescue Octokit::UnprocessableEntity, Octokit::NotFound
-        retry_count ||= 0
-        retry_count += 1
-        raise if retry_count > 10
-
-        sleep(rand(1..1.99))
-        retry
+      def label_pull_request(_pull_request_number)
+        raise "Only GitHub!"
       end
 
       private
 
-      attr_reader :source, :custom_labels, :credentials, :dependencies
+      attr_reader :source, :custom_labels, :dependencies
 
       def label_language?
         @label_language
@@ -226,183 +210,37 @@ def language_label_exists?
       end
 
       def language_label
-        label_name =
-          self.class.label_details_for_package_manager(package_manager).
-          fetch(:name)
-        labels.find { |l| l.casecmp(label_name).zero? }
+        labels.find { |l| l.casecmp(language_name).zero? }
       end
 
       def labels
-        @labels ||=
-          case source.provider
-          when "github" then fetch_github_labels
-          when "gitlab" then fetch_gitlab_labels
-          when "azure" then fetch_azure_labels
-          else raise "Unsupported provider #{source.provider}"
-          end
-      end
-
-      def fetch_github_labels
-        client = github_client_for_source
-
-        labels =
-          client.
-          labels(source.repo, per_page: 100).
-          map(&:name)
-
-        next_link = client.last_response.rels[:next]
-
-        while next_link
-          next_page = next_link.get
-          labels += next_page.data.map(&:name)
-          next_link = next_page.rels[:next]
-        end
-
-        labels
-      end
-
-      def fetch_gitlab_labels
-        gitlab_client_for_source.
-          labels(source.repo, per_page: 100).
-          auto_paginate.
-          map(&:name)
-      end
-
-      def fetch_azure_labels
-        langauge_name =
-          self.class.label_details_for_package_manager(package_manager).
-          fetch(:name)
-
-        @labels = [
-          *@labels,
-          DEFAULT_DEPENDENCIES_LABEL,
-          DEFAULT_SECURITY_LABEL,
-          langauge_name
-        ].uniq
+        raise "Unsupported provider #{source.provider}"
       end
 
       def create_dependencies_label
-        case source.provider
-        when "github" then create_github_dependencies_label
-        when "gitlab" then create_gitlab_dependencies_label
-        when "azure" then @labels # Azure does not have centralised labels
-        else raise "Unsupported provider #{source.provider}"
-        end
+        raise "Unsupported provider #{source.provider}"
       end
 
       def create_security_label
-        case source.provider
-        when "github" then create_github_security_label
-        when "gitlab" then create_gitlab_security_label
-        when "azure" then @labels # Azure does not have centralised labels
-        else raise "Unsupported provider #{source.provider}"
-        end
+        raise "Unsupported provider #{source.provider}"
       end
 
       def create_language_label
-        case source.provider
-        when "github" then create_github_language_label
-        when "gitlab" then create_gitlab_language_label
-        when "azure" then @labels # Azure does not have centralised labels
-        else raise "Unsupported provider #{source.provider}"
-        end
-      end
-
-      def create_github_dependencies_label
-        github_client_for_source.add_label(
-          source.repo, DEFAULT_DEPENDENCIES_LABEL, "0366d6",
-          description: "Pull requests that update a dependency file",
-          accept: "application/vnd.github.symmetra-preview+json"
-        )
-        @labels = [*@labels, DEFAULT_DEPENDENCIES_LABEL].uniq
-      rescue Octokit::UnprocessableEntity => e
-        raise unless e.errors.first.fetch(:code) == "already_exists"
-
-        @labels = [*@labels, DEFAULT_DEPENDENCIES_LABEL].uniq
-      end
-
-      def create_gitlab_dependencies_label
-        gitlab_client_for_source.create_label(
-          source.repo, DEFAULT_DEPENDENCIES_LABEL, "#0366d6",
-          description: "Pull requests that update a dependency file"
-        )
-        @labels = [*@labels, DEFAULT_DEPENDENCIES_LABEL].uniq
-      end
-
-      def create_github_security_label
-        github_client_for_source.add_label(
-          source.repo, DEFAULT_SECURITY_LABEL, "ee0701",
-          description: "Pull requests that address a security vulnerability",
-          accept: "application/vnd.github.symmetra-preview+json"
-        )
-        @labels = [*@labels, DEFAULT_SECURITY_LABEL].uniq
-      rescue Octokit::UnprocessableEntity => e
-        raise unless e.errors.first.fetch(:code) == "already_exists"
-
-        @labels = [*@labels, DEFAULT_SECURITY_LABEL].uniq
-      end
-
-      def create_gitlab_security_label
-        gitlab_client_for_source.create_label(
-          source.repo, DEFAULT_SECURITY_LABEL, "#ee0701",
-          description: "Pull requests that address a security vulnerability"
-        )
-        @labels = [*@labels, DEFAULT_SECURITY_LABEL].uniq
-      end
-
-      def create_github_language_label
-        langauge_name =
-          self.class.label_details_for_package_manager(package_manager).
-          fetch(:name)
-        github_client_for_source.add_label(
-          source.repo,
-          langauge_name,
-          self.class.label_details_for_package_manager(package_manager).
-            fetch(:colour),
-          description: "Pull requests that update #{langauge_name.capitalize} "\
-                       "code",
-          accept: "application/vnd.github.symmetra-preview+json"
-        )
-        @labels = [*@labels, langauge_name].uniq
-      rescue Octokit::UnprocessableEntity => e
-        raise unless e.errors.first.fetch(:code) == "already_exists"
-
-        @labels = [*@labels, langauge_name].uniq
-      end
-
-      def create_gitlab_language_label
-        langauge_name =
-          self.class.label_details_for_package_manager(package_manager).
-          fetch(:name)
-        gitlab_client_for_source.create_label(
-          source.repo,
-          langauge_name,
-          "#" + self.class.label_details_for_package_manager(package_manager).
-                fetch(:colour)
-        )
-        @labels = [*@labels, langauge_name].uniq
-      end
-
-      def github_client_for_source
-        @github_client_for_source ||=
-          Dependabot::Clients::GithubWithRetries.for_source(
-            source: source,
-            credentials: credentials
-          )
-      end
-
-      def gitlab_client_for_source
-        @gitlab_client_for_source ||=
-          Dependabot::Clients::GitlabWithRetries.for_source(
-            source: source,
-            credentials: credentials
-          )
+        raise "Unsupported provider #{source.provider}"
       end
 
       def package_manager
         @package_manager ||= dependencies.first.package_manager
       end
 
+      def language_name
+        @language_name ||= self.class.label_details_for_package_manager(package_manager).fetch(:name)
+      end
+
+      def colour
+        @colour ||= self.class.label_details_for_package_manager(package_manager).fetch(:colour)
+      end
+
       def version_class
         Utils.version_class_for_package_manager(package_manager)
       end

common/lib/dependabot/pull_request_creator/labelers/azure.rb

@@ -0,0 +1,34 @@
+# frozen_string_literal: true
+
+require "dependabot/pull_request_creator/labeler"
+
+module Dependabot
+  class PullRequestCreator
+    module Labelers
+      class Azure < Labeler
+        @package_manager_labels = {}
+
+        # Azure does not have centralised labels
+        def labels
+          @labels ||= [
+            DEFAULT_DEPENDENCIES_LABEL,
+            DEFAULT_SECURITY_LABEL,
+            language_name
+          ]
+        end
+
+        def create_dependencies_label
+          labels
+        end
+
+        def create_security_label
+          labels
+        end
+
+        def create_language_label
+          labels
+        end
+      end
+    end
+  end
+end

common/lib/dependabot/pull_request_creator/labelers/factory.rb

@@ -0,0 +1,77 @@
+# frozen_string_literal: true
+
+module Dependabot
+  class PullRequestCreator
+    module Labelers
+      class Factory
+        class << self
+          def for_source(source:, custom_labels:, credentials:, includes_security_fixes:, dependencies:,
+                         label_language:, automerge_candidate:)
+            labeler_params = {
+              custom_labels: custom_labels,
+              includes_security_fixes: includes_security_fixes,
+              dependencies: dependencies,
+              label_language: label_language,
+              automerge_candidate: automerge_candidate
+            }
+
+            case source.provider
+            when "github" then github_labeler(source, credentials, labeler_params)
+            when "gitlab" then gitlab_labeler(source, credentials, labeler_params)
+            when "azure" then azure_labeler(source, labeler_params)
+            when "bitbucket" then base_labeler(source, labeler_params)
+            when "codecommit" then base_labeler(source, labeler_params)
+            else raise "Unsupported provider '#{source.provider}'."
+            end
+          end
+
+          private
+
+          def github_labeler(source, credentials, labeler_params)
+            require "dependabot/pull_request_creator/labelers/github"
+            require "dependabot/clients/github_with_retries"
+            client = Dependabot::Clients::GithubWithRetries.for_source(
+              source: source,
+              credentials: credentials
+            )
+            Dependabot::PullRequestCreator::Labelers::Github.new(
+              source: source,
+              client: client,
+              **labeler_params
+            )
+          end
+
+          def gitlab_labeler(source, credentials, labeler_params)
+            require "dependabot/pull_request_creator/labelers/gitlab"
+            require "dependabot/clients/gitlab_with_retries"
+            client = Dependabot::Clients::GitlabWithRetries.for_source(
+              source: source,
+              credentials: credentials
+            )
+            Dependabot::PullRequestCreator::Labelers::Gitlab.new(
+              source: source,
+              client: client,
+              **labeler_params
+            )
+          end
+
+          def azure_labeler(source, labeler_params)
+            require "dependabot/pull_request_creator/labelers/azure"
+            Dependabot::PullRequestCreator::Labelers::Azure.new(
+              source: source,
+              **labeler_params
+            )
+          end
+
+          def base_labeler(source, labeler_params)
+            require "dependabot/pull_request_creator/labeler"
+            Dependabot::PullRequestCreator.Labeler.new(
+              source: source,
+              **labeler_params
+            )
+          end
+        end
+      end
+    end
+  end
+end