Function TestEndToEnd_json

log/sanitize_test.go:362–420

TestEndToEnd_json verifies the final JSON output produced by go-kit when logging values wrapped with DropUnsafeChars or EscapeUnsafeChars.

(t *testing.T)

// when logging values wrapped with DropUnsafeChars or
// EscapeUnsafeChars.
func TestEndToEnd_json(t *testing.T) {
	testCases := map[string]struct {
		value      any
		wantOnWire map[string]string
	}{
		"clean string passes through both wrappers unchanged": {
			value: "Mozilla/5.0",
			wantOnWire: map[string]string{
				"drop":   `{"user_agent":"Mozilla/5.0"}`,
				"escape": `{"user_agent":"Mozilla/5.0"}`,
			},
		},
		"embedded newline is sanitized before reaching the encoder": {
			value: "Mozilla\nFAKE",
			wantOnWire: map[string]string{
				"drop":   `{"user_agent":"MozillaFAKE"}`,
				"escape": `{"user_agent":"Mozilla\\x0aFAKE"}`,
			},
		},
		"custom Stringer rendering user-controlled text is sanitized": {
			value: testUnsafeUserInputStringer{"path=/foo\nFAKE"},
			wantOnWire: map[string]string{
				"drop":   `{"user_agent":"path=/fooFAKE"}`,
				"escape": `{"user_agent":"path=/foo\\x0aFAKE"}`,
			},
		},
		"typed-nil error renders as JSON null, matching go-kit raw output": {
			value: (*testNilSafeError)(nil),
			wantOnWire: map[string]string{
				"drop":   `{"user_agent":null}`,
				"escape": `{"user_agent":null}`,
			},
		},
		"nil any renders as JSON null, matching go-kit raw output": {
			value: nil,
			wantOnWire: map[string]string{
				"drop":   `{"user_agent":null}`,
				"escape": `{"user_agent":null}`,
			},
		},
	}

	for name, tc := range testCases {
		t.Run(name, func(t *testing.T) {
			t.Run("drop", func(t *testing.T) {
				buf := &bytes.Buffer{}
				logger := log.NewJSONLogger(buf)
				require.NoError(t, logger.Log("user_agent", DropUnsafeChars(tc.value)))
				require.JSONEq(t, tc.wantOnWire["drop"], buf.String())
			})
			t.Run("escape", func(t *testing.T) {
				buf := &bytes.Buffer{}
				logger := log.NewJSONLogger(buf)
				require.NoError(t, logger.Log("user_agent", EscapeUnsafeChars(tc.value)))
				require.JSONEq(t, tc.wantOnWire["escape"], buf.String())
			})
		})
	}