chore: Rework git auth for compatibility with github actions environm…

…ent (googleapis#8298)

.toys/.lib/pull_request_generator.rb

@@ -13,6 +13,7 @@
 # limitations under the License.
 
 require "json"
+require "base64"
 
 module PullRequestGenerator
   def ensure_pull_request_generation_dependencies
@@ -37,6 +38,7 @@ def generate_pull_request git_remote:,
   end
 
   @dependencies_checked = false
+  @created_fork = false
 
   class << self
     def generate context:,
@@ -46,10 +48,14 @@ def generate context:,
                  pr_body: nil
       if git_remote
         ensure_dependencies context: context
+        created_fork_name = environment_fork_name context: context if @created_fork
+        github_token = environment_github_token context: context
         impl = Impl.new context: context,
                         git_remote: git_remote,
                         branch_name: branch_name,
                         commit_message: commit_message,
+                        created_fork_name: created_fork_name,
+                        github_token: github_token,
                         pr_body: pr_body
         impl.start
         yield
@@ -71,16 +77,14 @@ def ensure_dependencies context:
     end
 
     def ensure_fork context:, git_remote:
+      ensure_dependencies context: context
       git_remote ||= "pull-request-fork"
+      fork_name = environment_fork_name context: context
       context.exec ["gh", "repo", "fork", "--remote=false"]
-      repo = ::JSON.parse(context.capture(["gh", "repo", "view", "--json=name"]))["name"]
-      owner = ::JSON.parse(context.capture(["gh", "api", "/user"]))["login"]
-      context.exec ["gh", "repo", "sync", "#{owner}/#{repo}"]
+      context.exec ["gh", "repo", "sync", fork_name]
       unless context.exec(["git", "remote", "get-url", git_remote], e: false, out: :capture, err: :capture).success?
-        token = environment_github_token context: context
-        cmd = ["git", "remote", "add", git_remote, "https://#{owner}:#{token}@github.com/#{owner}/#{repo}.git"]
-        log = ["git", "remote", "add", git_remote, "https://#{owner}:xxxxxxxx@github.com/#{owner}/#{repo}.git"]
-        context.exec cmd, log_cmd: log.inspect
+        context.exec ["git", "remote", "add", git_remote, "https://github.com/#{fork_name}.git"]
+        @created_fork = true
       end
       git_remote
     end
@@ -128,8 +132,16 @@ def ensure_git_identity context:
       context.exec ["git", "config", "--global", "user.name", "Yoshi Automation Bot"]
     end
 
+    def environment_fork_name context:
+      @fork_name ||= begin
+        repo = JSON.parse(context.capture(["gh", "repo", "view", "--json=name"]))["name"]
+        owner = JSON.parse(context.capture(["gh", "api", "/user"]))["login"]
+        "#{owner}/#{repo}"
+      end
+    end
+
     def environment_github_token context:
-      @environment_github_token ||= ENV["GITHUB_TOKEN"] || begin
+      @github_token ||= ENV["GITHUB_TOKEN"] || begin
         result = context.exec ["gh", "auth", "status", "-t"], e: false, out: :capture, err: [:child, :out]
         raise "Failed to get github token" unless result.success? && result.captured_out =~ /Token: (\w+)/
         Regexp.last_match[1]
@@ -142,12 +154,16 @@ def initialize git_remote:,
                    context:,
                    branch_name: nil,
                    commit_message: nil,
+                   created_fork_name: nil,
+                   github_token: nil,
                    pr_body: nil
       @git_remote = git_remote
       @context = context
       @branch_name = branch_name || generate_default_branch_name
       @commit_message = commit_message || generate_default_commit_message
       @pr_body = pr_body || generate_default_pr_body
+      @created_fork_name = created_fork_name
+      @github_token = github_token
     end
 
     def start
@@ -167,7 +183,16 @@ def finish
       if result
         @context.exec ["git", "add", "."]
         @context.exec ["git", "commit", "-m", @commit_message]
-        @context.exec ["git", "push", "-u", @git_remote, @branch_name]
+        log = cmd = ["git", "push", "-u", @git_remote, @branch_name]
+        if @github_token && @created_fork_name
+          username = @created_fork_name.split("/").first
+          credential = Base64.encode64 "#{username}:#{@github_token}"
+          cmd += [
+            "-c", "http.https://github.com/.extraheader=",
+            "-c", "http.https://github.com/#{@created_fork_name}.extraheader=AUTHORIZATION: basic #{credential}"
+          ]
+        end
+        @context.exec cmd, log_cmd: "exec: #{log.inspect}"
         @context.exec ["gh", "pr", "create",
                        "--title", @commit_message,
                        "--body", @pr_body]