package xds import ( "flag" "fmt" "os" "path/filepath" "testing" "github.com/golang/protobuf/jsonpb" "github.com/golang/protobuf/proto" "github.com/hashicorp/go-version" "github.com/stretchr/testify/require" ) // update allows golden files to be updated based on the current output. var update = flag.Bool("update", false, "update golden files") // goldenSimple is just for read/write access to a golden file that is not // envoy specific. func goldenSimple(t *testing.T, name, got string) string { return golden(t, name, "", "", got) } // goldenEnvoy is a special variant of golden() that silos each named test by // each supported envoy version func goldenEnvoy(t *testing.T, name, envoyVersion, latestEnvoyVersion, got string) string { t.Helper() require.NotEmpty(t, envoyVersion) // We'll need both the name of this golden file for the requested version // of envoy AND the latest version of envoy due to how the golden file // coalescing works below when there is no xDS generated skew across envoy // versions. subname := goldenEnvoyVersionName(t, envoyVersion) latestSubname := "latest" if envoyVersion == latestEnvoyVersion { subname = "latest" } return golden(t, name, subname, latestSubname, got) } func goldenEnvoyVersionName(t *testing.T, envoyVersion string) string { t.Helper() require.NotEmpty(t, envoyVersion) // We do version sniffing on the complete version, but only generate // golden files ignoring the patch portion version := version.Must(version.NewVersion(envoyVersion)) segments := version.Segments() require.Len(t, segments, 3) return fmt.Sprintf("envoy-%d-%d-x", segments[0], segments[1]) } // golden reads and optionally writes the expected data to the golden file, // returning the contents as a string. // // The golden file is named with two components the "name" and the "subname". // In the common case of xDS tests the "name" component is the logical name of // the test itself, and the "subname" is derived from the envoy major version. // // If latestSubname is specified we use that as a fallback source of comparison // if the specific golden file referred to by subname is absent. // // If the -update flag is passed when executing the tests then the contents of // the "got" argument are written to the golden file on disk. If the // latestSubname argument is specified in this mode and the generated content // matches that of the latest generated content then the specific golden file // referred to by 'subname' is deleted to avoid unnecessary duplication in the // testdata directory. func golden(t *testing.T, name, subname, latestSubname, got string) string { t.Helper() suffix := ".golden" if subname != "" { suffix = fmt.Sprintf(".%s.golden", subname) } golden := filepath.Join("testdata", name+suffix) // Always load the latest golden file if configured to do so. latestExpected := "" if latestSubname != "" && subname != latestSubname { latestGolden := filepath.Join("testdata", fmt.Sprintf("%s.%s.golden", name, latestSubname)) raw, err := os.ReadFile(latestGolden) require.NoError(t, err, "%q %q %q", name, subname, latestSubname) latestExpected = string(raw) } // Handle easy updates to the golden files in the agent/xds/testdata // directory. // // To trim down PRs, we only create per-version golden files if they differ // from the latest version. if *update && got != "" { if latestExpected == got { // In update mode we erase a golden file if it is identical to // the golden file corresponding to the latest version of // envoy. err := os.Remove(golden) if err != nil && !os.IsNotExist(err) { require.NoError(t, err) } return got } require.NoError(t, os.WriteFile(golden, []byte(got), 0644)) return got } expected, err := os.ReadFile(golden) if latestExpected != "" && os.IsNotExist(err) { // In readonly mode if a specific golden file isn't found, we fallback // on the latest one. return latestExpected } require.NoError(t, err) return string(expected) } func loadTestResource(t *testing.T, name string) string { t.Helper() expected, err := os.ReadFile(filepath.Join("testdata", name+".golden")) require.NoError(t, err) return string(expected) } func protoToJSON(t *testing.T, pb proto.Message) string { t.Helper() m := jsonpb.Marshaler{ Indent: " ", } gotJSON, err := m.MarshalToString(pb) require.NoError(t, err) return gotJSON }