Add latest changes from gitlab-org/gitlab@15-0-stable-eev15.0.0-rc42

1 files changed, 127 insertions, 0 deletions

diff --git a/scripts/lib/glfm/update_specification.rb b/scripts/lib/glfm/update_specification.rb
new file mode 100644
index 00000000000..73c23d40de5
--- /dev/null
+++ b/scripts/lib/glfm/update_specification.rb
@@ -0,0 +1,127 @@
+# frozen_string_literal: true
+require 'fileutils'
+require 'open-uri'
+require 'pathname'
+require_relative 'constants'
+require_relative 'shared'
+
+module Glfm
+  class UpdateSpecification
+    include Constants
+    include Shared
+
+    def process
+      output('Updating specification...')
+      ghfm_spec_txt_lines = load_ghfm_spec_txt
+      glfm_spec_txt_string = build_glfm_spec_txt(ghfm_spec_txt_lines)
+      write_glfm_spec_txt(glfm_spec_txt_string)
+    end
+
+    private
+
+    def load_ghfm_spec_txt
+      # We only re-download the GitHub Flavored Markdown specification if the
+      # UPDATE_GHFM_SPEC_TXT environment variable is set to true, which should only
+      # ever be done manually and locally, never in CI. This provides some security
+      # protection against a possible injection attack vector, if the GitHub-hosted
+      # version of the spec is ever temporarily compromised with an injection attack.
+      #
+      # This also avoids doing external network access to download the file
+      # in CI jobs, which can avoid potentially flaky builds if the GitHub-hosted
+      # version of the file is temporarily unavailable.
+      if ENV['UPDATE_GHFM_SPEC_TXT'] == 'true'
+        download_and_write_ghfm_spec_txt
+      else
+        read_existing_ghfm_spec_txt
+      end
+    end
+
+    def read_existing_ghfm_spec_txt
+      output("Reading existing #{GHFM_SPEC_TXT_PATH}...")
+      File.open(GHFM_SPEC_TXT_PATH).readlines
+    end
+
+    def download_and_write_ghfm_spec_txt
+      output("Downloading #{GHFM_SPEC_TXT_URI}...")
+      ghfm_spec_txt_uri_io = URI.open(GHFM_SPEC_TXT_URI)
+
+      # Read IO stream into an array of lines for easy processing later
+      ghfm_spec_txt_lines = ghfm_spec_txt_uri_io.readlines
+      raise "Unable to read lines from #{GHFM_SPEC_TXT_URI}" if ghfm_spec_txt_lines.empty?
+
+      # Make sure the GHFM spec version has not changed
+      validate_expected_spec_version!(ghfm_spec_txt_lines[2])
+
+      # Reset IO stream and re-read into a single string for easy writing
+      # noinspection RubyNilAnalysis
+      ghfm_spec_txt_uri_io.seek(0)
+      ghfm_spec_txt_string = ghfm_spec_txt_uri_io.read
+      raise "Unable to read string from #{GHFM_SPEC_TXT_URI}" unless ghfm_spec_txt_string
+
+      output("Writing #{GHFM_SPEC_TXT_PATH}...")
+      GHFM_SPEC_TXT_PATH.dirname.mkpath
+      write_file(GHFM_SPEC_TXT_PATH, ghfm_spec_txt_string)
+
+      ghfm_spec_txt_lines
+    end
+
+    def validate_expected_spec_version!(version_line)
+      return if version_line =~ /\Aversion: #{GHFM_SPEC_VERSION}\Z/o
+
+      raise "GitHub Flavored Markdown spec.txt version mismatch! " \
+          "Expected 'version: #{GHFM_SPEC_VERSION}', got '#{version_line}'"
+    end
+
+    def build_glfm_spec_txt(ghfm_spec_txt_lines)
+      glfm_spec_txt_lines = ghfm_spec_txt_lines.dup
+      replace_header(glfm_spec_txt_lines)
+      replace_intro_section(glfm_spec_txt_lines)
+      insert_examples_txt(glfm_spec_txt_lines)
+      glfm_spec_txt_lines.join('')
+    end
+
+    def replace_header(spec_txt_lines)
+      spec_txt_lines[0, spec_txt_lines.index("...\n") + 1] = GLFM_SPEC_TXT_HEADER
+    end
+
+    def replace_intro_section(spec_txt_lines)
+      glfm_intro_txt_lines = File.open(GLFM_INTRO_TXT_PATH).readlines
+      raise "Unable to read lines from #{GLFM_INTRO_TXT_PATH}" if glfm_intro_txt_lines.empty?
+
+      ghfm_intro_header_begin_index = spec_txt_lines.index do |line|
+        line =~ INTRODUCTION_HEADER_LINE_TEXT
+      end
+      raise "Unable to locate introduction header line in #{GHFM_SPEC_TXT_PATH}" if ghfm_intro_header_begin_index.nil?
+
+      # Find the index of the next header after the introduction header, starting from the index
+      # of the introduction header this is the length of the intro section
+      ghfm_intro_section_length = spec_txt_lines[ghfm_intro_header_begin_index + 1..].index do |line|
+        line.start_with?('# ')
+      end
+
+      # Replace the intro section with the GitLab flavored Markdown intro section
+      spec_txt_lines[ghfm_intro_header_begin_index, ghfm_intro_section_length] = glfm_intro_txt_lines
+    end
+
+    def insert_examples_txt(spec_txt_lines)
+      glfm_examples_txt_lines = File.open(GLFM_EXAMPLES_TXT_PATH).readlines
+      raise "Unable to read lines from #{GLFM_EXAMPLES_TXT_PATH}" if glfm_examples_txt_lines.empty?
+
+      ghfm_end_tests_comment_index = spec_txt_lines.index do |line|
+        line =~ END_TESTS_COMMENT_LINE_TEXT
+      end
+      raise "Unable to locate 'END TESTS' comment line in #{GHFM_SPEC_TXT_PATH}" if ghfm_end_tests_comment_index.nil?
+
+      # Insert the GLFM examples before the 'END TESTS' comment line
+      spec_txt_lines[ghfm_end_tests_comment_index - 1] = ["\n", glfm_examples_txt_lines, "\n"].flatten
+
+      spec_txt_lines
+    end
+
+    def write_glfm_spec_txt(glfm_spec_txt_string)
+      output("Writing #{GLFM_SPEC_TXT_PATH}...")
+      FileUtils.mkdir_p(Pathname.new(GLFM_SPEC_TXT_PATH).dirname)
+      write_file(GLFM_SPEC_TXT_PATH, glfm_spec_txt_string)
+    end
+  end
+end