Hello World error

Demonstrates how to report an error.

Explore further

For detailed documentation that includes this code sample, see the following:

• Report errors
• Report runtime function errors (1st gen)

Code sample

Go

To authenticate to Cloud Run functions, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

package tips

import (
	"fmt"
	"net/http"
	"os"

	"github.com/GoogleCloudPlatform/functions-framework-go/functions"
)

func init() {
	functions.HTTP("HTTPError", HTTPError)
}

// HTTPError describes how errors are handled in an HTTP function.
func HTTPError(w http.ResponseWriter, r *http.Request) {
	// An error response code is NOT reported to Error Reporting.
	// http.Error(w, "An error occurred", http.StatusInternalServerError)

	// Printing to stdout and stderr is NOT reported to Error Reporting.
	fmt.Println("An error occurred (stdout)")
	fmt.Fprintln(os.Stderr, "An error occurred (stderr)")

	// Calling log.Fatal sets a non-zero exit code and is NOT reported to Error
	// Reporting.
	// log.Fatal("An error occurred (log.Fatal)")

	// Panics are reported to Error Reporting.
	panic("An error occurred (panic)")
}

Java

To authenticate to Cloud Run functions, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

import com.google.cloud.functions.HttpFunction;
import com.google.cloud.functions.HttpRequest;
import com.google.cloud.functions.HttpResponse;
import java.io.IOException;
import java.util.logging.Logger;

public class HelloError implements HttpFunction {

  private static final Logger logger = Logger.getLogger(HelloError.class.getName());

  @Override
  public void service(HttpRequest request, HttpResponse response)
      throws IOException {
    // These will NOT be reported to Error Reporting
    System.err.println("I failed you");
    logger.severe("I failed you");

    // This WILL be reported to Error Reporting
    throw new RuntimeException("I failed you");
  }
}

Node.js

To authenticate to Cloud Run functions, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

// These WILL be reported to Error Reporting
throw new Error('I failed you'); // Will cause a cold start if not caught

Python

To authenticate to Cloud Run functions, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

@functions_framework.http
def hello_error_1(request):
    # This WILL be reported to Error Reporting,
    # and WILL NOT show up in logs or
    # terminate the function.
    from google.cloud import error_reporting

    client = error_reporting.Client()

    try:
        raise RuntimeError("I failed you")
    except RuntimeError:
        client.report_exception()

    # This WILL be reported to Error Reporting,
    # and WILL terminate the function
    raise RuntimeError("I failed you")


@functions_framework.http
def hello_error_2(request):
    # These errors WILL NOT be reported to Error
    # Reporting, but will show up in logs.
    import logging
    import sys

    print(RuntimeError("I failed you (print to stdout)"))
    logging.warning(RuntimeError("I failed you (logging.warning)"))
    logging.error(RuntimeError("I failed you (logging.error)"))
    sys.stderr.write("I failed you (sys.stderr.write)\n")

    # This is considered a successful execution and WILL NOT be reported
    # to Error Reporting, but the status code (500) WILL be logged.
    from flask import abort

    return abort(500)

What's next

To search and filter code samples for other Google Cloud products, see the Google Cloud sample browser.