Method Search

internal/sourcebackend/sourcebackend.go:293–638

Reads a single JSON request from the TCP connection, performs the search and sends results back over the TCP connection as they appear.

(in *sourcebackendpb.SearchRequest, stream sourcebackendpb.SourceBackend_SearchServer)

	flags := syntax.Perl
	if in.GetLiteral() {
		flags |= syntax.Literal
	}
	re, err := syntax.Parse(in.Query, flags)
	if err != nil {
		return err
	}

	// Parse the (rewritten) URL to extract all ranking options/keywords.
	rewritten, err := url.Parse(in.RewrittenUrl)
	if err != nil {
		return err
	}
	rankingopts := ranking.RankingOptsFromQuery(rewritten.Query())

	// TODO: analyze the query to see if fast path can be taken
	// maybe by using a different worker?
	simplified := re.Simplify()
	caseSensitive := simplified.Flags&syntax.FoldCase != 0
	queryPos := s.UsePositionalIndex && simplified.Op == syntax.OpLiteral && !caseSensitive
	var files ranking.ResultPaths
	if queryPos {
		possible, err := s.queryPositional(string(simplified.Rune))
		if err != nil {
			return err
		}
		files = make(ranking.ResultPaths, 0, len(possible))
		for _, entry := range possible {
			result := ranking.ResultPath{
				Path:     entry.fn,
				Position: int(entry.pos),
			}
			result.Rank(s.RankingMap, &rankingopts)
			if result.Ranking > -1 {
				files = append(files, result)
			}
		}
	} else {
		possible, err := s.query(index.RegexpQuery(re))
		if err != nil {
			return err
		}

		// Rank all the paths.
		files = make(ranking.ResultPaths, 0, len(possible))
		for _, filename := range possible {
			result := ranking.ResultPath{Path: filename}
			result.Rank(s.RankingMap, &rankingopts)
			if result.Ranking > -1 {
				files = append(files, result)
			}
		}

	}

	// Filter all files that should be excluded.
	files = FilterByKeywords(rewritten, files)

	// While not strictly necessary, this will lead to better results being