GenerateSponsorsYamlFileJob: stable branch, reuse PR & extract GitHubPusher

app/jobs/generate_sponsors_yaml_file_job.rb

@@ -1,6 +1,4 @@
 class GenerateSponsorsYamlFileJob < ApplicationJob
-  delegate :octokit, :base_branch, to: :github_installation
-
   def perform(conference, push: true)
     @conference = conference
 
@@ -128,50 +126,119 @@ def json_data
 
   def push_to_github
     return unless repo
-    return if yaml_data.nil? # to generate
+    return if yaml_data.nil?
+
     push_id = @last_id || "event-#{@last_event_editing_history_id}"
-    @branch_name = "sponsor-app/#{push_id}"
-    @filepath = repo.path
+    GitHubPusher.new(
+      conference: @conference,
+      filepath: repo.path,
+      content: yaml_data,
+      last_editing_history_id: @last_id,
+      push_id:,
+    ).push
+  end
+
+  # For debugging
+  def self.get_octokit(repo)
+    GithubInstallation.new(repo).octokit
+  end
+
+  class GitHubPusher
+    MAX_RETRIES = 3
 
-    begin
-      octokit.delete_branch(repo.name, @branch_name)
-    rescue Octokit::UnprocessableEntity
+    delegate :octokit, :base_branch, to: :github_installation
+
+    def initialize(conference:, filepath:, content:, last_editing_history_id:, push_id:)
+      @conference = conference
+      @repo = conference.github_repo
+      @filepath = filepath
+      @content = content
+      @last_id = last_editing_history_id
+      @branch_name = "sponsor-app/#{conference.slug}"
+      @pr_title = "Update sponsors.yml for #{conference.slug} (#{push_id})"
     end
 
-    head = octokit.branch(repo.name, base_branch)
-    octokit.create_ref(repo.name, "refs/heads/#{@branch_name}", head[:commit][:sha])
+    def push
+      return unless @repo
 
-    begin
-      blob_sha = octokit.contents(repo.name, path: @filepath)[:sha]
-    rescue Octokit::NotFound
-      blob_sha = nil
+      if branch_has_newer_data?
+        Rails.logger.info "GenerateSponsorsYamlFileJob: branch has newer data, skipping"
+        return
+      end
+
+      reset_branch
+      commit_content
+      create_or_update_pull_request
     end
 
-    octokit.update_contents(
-      repo.name,
-      @filepath,
-      "Update sponsors.yml for #{@conference.slug} (#{push_id})",
-      blob_sha,
-      yaml_data,
-      branch: @branch_name,
-    )
-    octokit.create_pull_request(
-      repo.name,
-      base_branch,
-      @branch_name,
-      "Update sponsors.yml for #{@conference.slug} (#{push_id})",
-      nil,
-    )
-  end
+    private
 
-  # For debugging
-  def self.get_octokit(repo)
-    GithubInstallation.new(repo).octokit
-  end
+    def reset_branch
+      begin
+        octokit.delete_branch(@repo.name, @branch_name)
+      rescue Octokit::UnprocessableEntity
+      end
+
+      head = octokit.branch(@repo.name, base_branch)
+      octokit.create_ref(@repo.name, "refs/heads/#{@branch_name}", head[:commit][:sha])
+    end
+
+    def commit_content
+      begin
+        blob_sha = octokit.contents(@repo.name, path: @filepath)[:sha]
+      rescue Octokit::NotFound
+        blob_sha = nil
+      end
+
+      retries = 0
+      begin
+        octokit.update_contents(@repo.name, @filepath, @pr_title, blob_sha, @content, branch: @branch_name)
+      rescue Octokit::Conflict, Octokit::UnprocessableEntity => e
+        if retries < MAX_RETRIES && !branch_has_newer_data?
+          retries += 1
+          begin
+            blob_sha = octokit.contents(@repo.name, path: @filepath, ref: @branch_name)[:sha]
+          rescue Octokit::NotFound
+            blob_sha = nil
+          end
+          Rails.logger.info "GenerateSponsorsYamlFileJob: commit conflict, retrying (#{retries}/#{MAX_RETRIES})"
+          retry
+        else
+          Rails.logger.info "GenerateSponsorsYamlFileJob: commit conflict and branch has newer data (or max retries), skipping"
+          return
+        end
+      end
+    end
+
+    def branch_has_newer_data?
+      existing = octokit.contents(@repo.name, path: @filepath, ref: @branch_name)
+      existing_content = Base64.decode64(existing[:content])
+      if existing_content =~ /last_editing_history: (\d+)/
+        return @last_id && $1.to_i > @last_id
+      end
+      false
+    rescue Octokit::NotFound
+      false # Branch or file doesn't exist
+    end
 
-  private
+    def create_or_update_pull_request
+      owner = @repo.name.split('/')[0]
+      existing_prs = octokit.pull_requests(@repo.name, state: 'open', head: "#{owner}:#{@branch_name}")
+      if existing_prs.any?
+        octokit.update_pull_request(@repo.name, existing_prs[0][:number], title: @pr_title)
+      else
+        begin
+          octokit.create_pull_request(@repo.name, base_branch, @branch_name, @pr_title, nil)
+        rescue Octokit::UnprocessableEntity
+          # Concurrent job already created PR
+          existing_prs = octokit.pull_requests(@repo.name, state: 'open', head: "#{owner}:#{@branch_name}")
+          octokit.update_pull_request(@repo.name, existing_prs[0][:number], title: @pr_title) if existing_prs.any?
+        end
+      end
+    end
 
-  def github_installation
-    @github_installation ||= GithubInstallation.new(repo.name, branch: repo.branch)
+    def github_installation
+      @github_installation ||= GithubInstallation.new(@repo.name, branch: @repo.branch)
+    end
   end
 end