module Gitlab module Diff module FileCollection class MergeRequestDiff < Base def initialize(merge_request_diff, diff_options:) @merge_request_diff = merge_request_diff super(merge_request_diff, project: merge_request_diff.project, diff_options: diff_options, diff_refs: merge_request_diff.diff_refs, fallback_diff_refs: merge_request_diff.fallback_diff_refs) end def diff_files # Make sure to _not_ send any method call to Gitlab::Diff::File # _before_ all of them were collected (`super`). Premature method calls will # trigger N+1 RPCs to Gitaly through BatchLoader records (Blob.lazy). # diff_files = super diff_files.each { |diff_file| cache_highlight!(diff_file) if cacheable?(diff_file) } store_highlight_cache diff_files end def real_size @merge_request_diff.real_size end def clear_cache! Rails.cache.delete(cache_key) end def cache_key [@merge_request_diff, 'highlighted-diff-files', diff_options] end private def highlight_diff_file_from_cache!(diff_file, cache_diff_lines) diff_file.highlighted_diff_lines = cache_diff_lines.map do |line| Gitlab::Diff::Line.init_from_hash(line) end end # # If we find the highlighted diff files lines on the cache we replace existing diff_files lines (no highlighted) # for the highlighted ones, so we just skip their execution. # If the highlighted diff files lines are not cached we calculate and cache them. # # The content of the cache is a Hash where the key identifies the file and the values are Arrays of # hashes that represent serialized diff lines. # def cache_highlight!(diff_file) item_key = diff_file.file_identifier if highlight_cache[item_key] highlight_diff_file_from_cache!(diff_file, highlight_cache[item_key]) else highlight_cache[item_key] = diff_file.highlighted_diff_lines.map(&:to_hash) end end def highlight_cache return @highlight_cache if defined?(@highlight_cache) @highlight_cache = Rails.cache.read(cache_key) || {} @highlight_cache_was_empty = @highlight_cache.empty? @highlight_cache end def store_highlight_cache Rails.cache.write(cache_key, highlight_cache, expires_in: 1.week) if @highlight_cache_was_empty end def cacheable?(diff_file) @merge_request_diff.present? && diff_file.text? && diff_file.diffable? end end end end end