fix(metrics): addDimensions() documentation and tests

[matteofigus]

Fix: addDimensions() should create a set

Summary

Changes

This PR fixes issue #3777 by modifying the addDimensions() method to create a new dimension set rather than concatenating dimensions into the existing set. The implementation follows the EMF specification which supports multiple dimension sets within the Dimensions array.

Issue number: #3777

Description of changes

Key changes:

• Modified addDimensions() to create a new dimension set that includes default dimensions
• Added an alias method addDimensionSet() for consistency with other Powertools for AWS Lambda implementations
• Updated serializeMetrics() to include all dimension sets in the EMF output
• Updated clearDimensions() to clear both individual dimensions and dimension sets
• Updated tests to verify the new behavior
• Added documentation for the new functionality

Example

const metrics = new Metrics({
  namespace: 'serverlessAirline',
  serviceName: 'orders',
});

// Add a single dimension
metrics.addDimension('environment', 'prod');

// Add a new dimension set
metrics.addDimensions({
  dimension1: "1",
  dimension2: "2"
});

// This will create two dimension sets in the EMF output:
// [["service", "environment"]] and [["service", "dimension1", "dimension2"]]
metrics.addMetric('successfulBooking', MetricUnit.Count, 1);
metrics.publishStoredMetrics();

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[boring-cyborg]

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In the meantime, check out the #typescript channel on our Powertools for AWS Lambda Discord: Invite link

[dreamorosi]

I'm a bit unsure about the changes in this entire file. It seems that we re-declared all the types that were previously in the packages/metrics/src/types/Metrics.ts file for no apparent reason.

This seems to break the compilation (see failed CI) - can we revert?

[matteofigus]

Thanks for catching this! I've reverted the types/index.ts file to its original state. This was an unintended change that happened during the implementation. The PR now only contains documentation updates and test fixes.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
17.6% Duplication on New Code

See analysis details on SonarQube Cloud