在 Cloud Run 中記錄及查看記錄檔

// Uncomment and populate this variable in your code:
// const project = 'The project ID of your function or Cloud Run service';

// Build structured log messages as an object.
const globalLogFields = {};

// Add log correlation to nest all log messages beneath request log in Log Viewer.
// (This only works for HTTP-based invocations where `req` is defined.)
if (typeof req !== 'undefined') {
  const traceHeader = req.header('X-Cloud-Trace-Context');
  if (traceHeader && project) {
    const [trace] = traceHeader.split('/');
    globalLogFields['logging.googleapis.com/trace'] =
      `projects/${project}/traces/${trace}`;
  }
}

// Complete a structured log entry.
const entry = Object.assign(
  {
    severity: 'NOTICE',
    message: 'This is the default display field.',
    // Log viewer accesses 'component' as 'jsonPayload.component'.
    component: 'arbitrary-property',
  },
  globalLogFields
);

// Serialize to a JSON string and output.
console.log(JSON.stringify(entry));

# Uncomment and populate this variable in your code:
# PROJECT = 'The project ID of your Cloud Run service';

# Build structured log messages as an object.
global_log_fields = {}

# Add log correlation to nest all log messages.
# This is only relevant in HTTP-based contexts, and is ignored elsewhere.
# (In particular, non-HTTP-based Cloud Functions.)
request_is_defined = "request" in globals() or "request" in locals()
if request_is_defined and request:
    trace_header = request.headers.get("X-Cloud-Trace-Context")

    if trace_header and PROJECT:
        trace = trace_header.split("/")
        global_log_fields[
            "logging.googleapis.com/trace"
        ] = f"projects/{PROJECT}/traces/{trace[0]}"

# Complete a structured log entry.
entry = dict(
    severity="NOTICE",
    message="This is the default display field.",
    # Log viewer accesses 'component' as jsonPayload.component'.
    component="arbitrary-property",
    **global_log_fields,
)

print(json.dumps(entry))

// Entry defines a log entry.
type Entry struct {
	Message  string `json:"message"`
	Severity string `json:"severity,omitempty"`
	Trace    string `json:"logging.googleapis.com/trace,omitempty"`

	// Logs Explorer allows filtering and display of this as `jsonPayload.component`.
	Component string `json:"component,omitempty"`
}

// String renders an entry structure to the JSON format expected by Cloud Logging.
func (e Entry) String() string {
	if e.Severity == "" {
		e.Severity = "INFO"
	}
	out, err := json.Marshal(e)
	if err != nil {
		log.Printf("json.Marshal: %v", err)
	}
	return string(out)
}

func init() {
	// Disable log prefixes such as the default timestamp.
	// Prefix text prevents the message from being parsed as JSON.
	// A timestamp is added when shipping logs to Cloud Logging.
	log.SetFlags(0)
}

func indexHandler(w http.ResponseWriter, r *http.Request) {
	// Uncomment and populate this variable in your code:
	// projectID = "The project ID of your Cloud Run service"

	// Derive the traceID associated with the current request.
	var trace string
	if projectID != "" {
		traceHeader := r.Header.Get("X-Cloud-Trace-Context")
		traceParts := strings.Split(traceHeader, "/")
		if len(traceParts) > 0 && len(traceParts[0]) > 0 {
			trace = fmt.Sprintf("projects/%s/traces/%s", projectID, traceParts[0])
		}
	}

	log.Println(Entry{
		Severity:  "NOTICE",
		Message:   "This is the default display field.",
		Component: "arbitrary-property",
		Trace:     trace,
	})

	fmt.Fprintln(w, "Hello Logger!")
}

// Add log correlation to nest all log messages beneath request log in Log Viewer.
// TODO(developer): delete this code if you're creating a Cloud
//                  Function and it is *NOT* triggered by HTTP.
String traceHeader = req.headers("x-cloud-trace-context");
if (traceHeader != null && project != null) {
  String trace = traceHeader.split("/")[0];
  MDC.put(
      "logging.googleapis.com/trace",
      String.format("projects/%s/traces/%s", project, trace));
}
// -- End log correlation code --

// Create a structured log entry using MDC (Mapped Diagnostic Context) keys.
// For instantiating the "logger" variable, see
// https://cloud.google.com/run/docs/logging#run_manual_logging-java
MDC.put("component", "arbitrary-property");

logger.info("This is the default display field.");

// Clear MDC at the end of the request to avoid resource leaks
MDC.clear();

<configuration>
  <appender name="CLOUD" class="com.google.cloud.logging.logback.LoggingAppender">
    <!-- Optional : filter logs at or above a level -->
    <filter class="ch.qos.logback.classic.filter.ThresholdFilter">
      <level>INFO</level>
    </filter>
    <log>application.log</log> <!-- Optional : default java.log -->
    <resourceType>gae_app</resourceType> <!-- Optional : default: auto-detected, fallback: global -->
    <enhancer>com.example.logging.logback.enhancers.ExampleEnhancer</enhancer> <!-- Optional -->
    <flushLevel>WARN</flushLevel> <!-- Optional : default ERROR -->
    <!-- Redirect logs to stdout in JSON format for Cloud Run to capture -->
    <redirectToStdout>true</redirectToStdout>
  </appender>
  <root level="INFO">
    <appender-ref ref="CLOUD"/>
  </root>
</configuration>

{"severity":"INFO","time":"YYYY-MM-DDTHH:MM:SS.SSSZ","logging.googleapis.com/labels":{"component":"arbitrary-property","levelName":"INFO","loggerName":"com.example.cloudrun.App","levelValue":"20000"},"logging.googleapis.com/trace_sampled":false,"message":"This is the default display field."}