@VisibleForTesting
    static String convertRegexPath(String patternString) {
        if (patternString.charAt(patternString.length() - 1) == '$') {
            patternString = patternString.substring(0, patternString.length() - 1);
        }
        if (patternString.charAt(0) == '^') {
            patternString = patternString.substring(1);
        }

        // map '/a/(?<p0>[^/]+):get' to '/a/p0:get'
        return PATH_PARAM_PATTERN.matcher(patternString).replaceAll("$1");
    }
{@link DocServicePlugin} implementation that supports {@link GrpcService}s.
grpc/src/main/java/com/linecorp/armeria/internal/server/grpc/GrpcDocServicePlugin.java