Class console

  • The console class enables developers to write logs to Google Cloud's Stackdriver Logging service with various severity levels (DEBUG, INFO, ERROR, WARNING).

  • It provides methods like console.log(), console.info(), console.error(), and console.warn() for logging messages with different severity.

  • Developers can use console.time() and console.timeEnd() to measure the execution time of specific code blocks.

  • The console methods accept format strings and values for structured logging, allowing objects and other data types to be included in log entries.

  • Log entries can be viewed and analyzed in the Stackdriver Logging interface for debugging and monitoring purposes.

console

This class allows the developer to write to the Execution log and to Google Cloud Logging if the script is associated with a standard Cloud Project.

For full support of Cloud Logging and structured logging, use Logger. The console methods serialize the objects to strings and do not support jsonPayload as part of the structured logging LogEntry.

function measuringExecutionTime() {
  const label = "myFunction() time"; // Labels the timing log entry.
  console.time(label); // Starts the timer.
  try {
    myFunction(); // Function to time.
  } catch (e) {
    // Logs an ERROR message.
    console.error("myFunction() yielded an error: " + e);
  }
  console.timeEnd(label); // Stops the timer, logs execution duration.
}

function myFunction() {
  // ...
}

Methods

MethodReturn typeBrief description
error()voidOutputs a blank ERROR level message to Stackdriver Logging.
error(formatOrObject, values)voidOutputs an ERROR level message to Stackdriver Logging.
info()voidOutputs blank INFO level message to Stackdriver Logging.
info(formatOrObject, values)voidOutputs an INFO level message to Stackdriver Logging.
log()voidOutputs a blank DEBUG level message to Stackdriver Logging.
log(formatOrObject, values)voidOutputs a DEBUG level message to Stackdriver Logging.
time(label)voidStarts a timer you can use to track how long an operation takes.
timeEnd(label)voidStops a timer that was previously started by calling console.time().
warn()voidOutputs a blank WARNING level message to Stackdriver Logging.
warn(formatOrObject, values)voidOutputs a WARNING level message to Stackdriver Logging.

Detailed documentation

error()

Outputs a blank ERROR level message to Stackdriver Logging.


error(formatOrObject, values)

Outputs an ERROR level message to Stackdriver Logging.

Parameters

NameTypeDescription
formatOrObjectObjecta string containing zero or more substitution strings, or a JavaScript object to be logged as a JavaScript object if no other parameters.
valuesObject...objects with which to replace substitution strings within the message. This gives you additional control over the format of the output.

info()

Outputs blank INFO level message to Stackdriver Logging.


info(formatOrObject, values)

Outputs an INFO level message to Stackdriver Logging.

Parameters

NameTypeDescription
formatOrObjectObjecta string containing zero or more substitution strings, or a JavaScript object to be logged as a JavaScript object if no other parameters.
valuesObject...objects with which to replace substitution strings within the message. This gives you additional control over the format of the output.

log()

Outputs a blank DEBUG level message to Stackdriver Logging.


log(formatOrObject, values)

Outputs a DEBUG level message to Stackdriver Logging.

Parameters

NameTypeDescription
formatOrObjectObjecta string containing zero or more substitution strings, or a JavaScript object to be logged as a JavaScript object if no other parameters.
valuesObject...objects with which to replace substitution strings within the message. This gives you additional control over the format of the output.

time(label)

Starts a timer you can use to track how long an operation takes.

Parameters

NameTypeDescription
labelStringThe name to give the new timer.

timeEnd(label)

Stops a timer that was previously started by calling console.time(). The time duration is logged in Stackdriver.

Parameters

NameTypeDescription
labelStringthe name of the timer to stop.

warn()

Outputs a blank WARNING level message to Stackdriver Logging.


warn(formatOrObject, values)

Outputs a WARNING level message to Stackdriver Logging.

Parameters

NameTypeDescription
formatOrObjectObjecta string containing zero or more substitution strings, or a JavaScript object to be logged as a JavaScript object if no other parameters.
valuesObject...objects with which to replace substitution strings within the message. This gives you additional control over the format of the output.