AtfLogFormatter

Defined in: packages/lambda-utils/src/logger.ts:82

Extends

• LogFormatter

Constructors

Constructor

new AtfLogFormatter(): AtfLogFormatter

Returns

AtfLogFormatter

Inherited from

LogFormatter.constructor

Methods

formatAttributes()

formatAttributes(attributes, additionalLogAttributes): LogItem

Defined in: packages/lambda-utils/src/logger.ts:83

Format key-value pairs of log attributes.

You should implement this method in a subclass to define the structure of the log item and instantiate a new LogItem object with the formatted attributes.

Note that when implementing this method, you should avoid mutating the attributes and additionalLogAttributes objects directly. Instead, create a new object with the desired structure and return it.

If mutation is necessary, you can create a structuredClone of the object to avoid side effects.

Parameters

attributes

UnformattedAttributes

Unformatted attributes

additionalLogAttributes

LogAttributes

Additional log attributes

Returns

LogItem

Example

import { LogFormatter, LogItem } from '@aws-lambda-powertools/logger';
import type {
  LogAttributes,
  UnformattedAttributes,
} from '@aws-lambda-powertools/logger/types';

class MyCompanyLogFormatter extends LogFormatter {
  public formatAttributes(
    attributes: UnformattedAttributes,
    additionalLogAttributes: LogAttributes
  ): LogItem {
    const baseAttributes = {
      message: attributes.message,
      service: attributes.serviceName,
      environment: attributes.environment,
      awsRegion: attributes.awsRegion,
      correlationIds: {
        awsRequestId: attributes.lambdaContext?.awsRequestId,
        xRayTraceId: attributes.xRayTraceId,
      },
      lambdaFunction: {
        name: attributes.lambdaContext?.functionName,
        arn: attributes.lambdaContext?.invokedFunctionArn,
        memoryLimitInMB: attributes.lambdaContext?.memoryLimitInMB,
        version: attributes.lambdaContext?.functionVersion,
        coldStart: attributes.lambdaContext?.coldStart,
      },
      logLevel: attributes.logLevel,
      timestamp: this.formatTimestamp(attributes.timestamp), // You can extend this function
      logger: {
        sampleRateValue: attributes.sampleRateValue,
      },
    };

    const logItem = new LogItem({ attributes: baseAttributes });
    // add any attributes not explicitly defined
    logItem.addAttributes(additionalLogAttributes);

    return logItem;
  }
}

export { MyCompanyLogFormatter };

Overrides

LogFormatter.formatAttributes

---

formatError()

formatError(error): LogAttributes

Defined in: packages/lambda-utils/src/logger.ts:113

Phase 3G — error formatting with a bundled code location.

name and location are unmasked: a code identifier and a bundled file:line:col are not PII and are the fields you click through on. message and stack may carry caller-supplied PII, so both are masked with the same rules as every other log value.

Parameters

error

Error

Returns

LogAttributes

Overrides

LogFormatter.formatError

---

formatTimestamp()

formatTimestamp(now): string

Defined in: node_modules/.pnpm/@aws-lambda-powertools+logger@2.34.0_@middy+core@7.7.0/node_modules/@aws-lambda-powertools/logger/lib/esm/formatter/LogFormatter.d.ts:107

Format a date into an ISO 8601 string with the configured timezone.

The timezone is read from the TZ environment variable, if present. Otherwise, the timezone defaults to ':UTC'.

Parameters

now

Date

The date to format

Returns

string

Inherited from

LogFormatter.formatTimestamp

---

getCodeLocation()

getCodeLocation(stack?): string

Defined in: packages/lambda-utils/src/logger.ts:128

Parse the first file:line:col frame out of an error stack. Returns "" for an empty/undefined stack or an unparseable one. Only the basename is kept (the bundled file), matching the standalone axis-tech-be-lib-logger behaviour adapted to Powertools v2.

Parameters

stack?

string

Returns

string

Overrides

LogFormatter.getCodeLocation