func GenTranslationInfoFromOPConfig()

in src/go/configgenerator/filtergen/path_rewrite.go [138:178]
32 lines of code
10 McCabe index (conditional complexity)

func GenTranslationInfoFromOPConfig(serviceConfig *confpb.Service, opts options.ConfigGeneratorOptions) (map[string]TranslationInfo, error) {
	if opts.EnableBackendAddressOverride {
		glog.Infof("Skipping create path rewrite translation info because backend address override is enabled.")
		return nil, nil
	}

	infoBySelector := make(map[string]TranslationInfo)
	for _, rule := range serviceConfig.GetBackend().GetRules() {
		if util.ShouldSkipOPDiscoveryAPI(rule.GetSelector(), opts.AllowDiscoveryAPIs) {
			glog.Warningf("Skip backend rule %q because discovery API is not supported.", rule.GetSelector())
			continue
		}

		if rule.GetAddress() == "" {
			glog.Infof("Skip backend rule %q because it does not have dynamic routing address.", rule.GetSelector())
			continue
		}

		_, _, _, path, err := util.ParseURI(rule.GetAddress())
		if err != nil {
			return nil, fmt.Errorf("error parsing remote backend rule's address for operation %q: %v", rule.GetAddress(), err)
		}

		// For CONSTANT_ADDRESS, an empty uri will generate an empty path header.
		// It is an invalid Http header if path is empty.
		if path == "" && rule.GetPathTranslation() == confpb.BackendRule_CONSTANT_ADDRESS {
			path = "/"
		}

		if path == "" || rule.GetPathTranslation() == confpb.BackendRule_PATH_TRANSLATION_UNSPECIFIED {
			continue
		}

		infoBySelector[rule.GetSelector()] = TranslationInfo{
			TranslationType: rule.GetPathTranslation(),
			Path:            path,
		}
	}

	return infoBySelector, nil
}