fix(metrics): emit warning when default dimensions are overwritten - #4222

Summary

Adds warning messages to the Metrics setDefaultDimensions method when overwriting existing default dimensions, ensuring consistency and parity with addDimension/addDimensions methods.

Changes

This pull request improves the robustness of the setDefaultDimensions method in the Metrics utility by:

• Moved setEnvConfig() and setConsole() calls from setOptions() to the constructor to ensure logger is initialized before any method uses it.
• Ensuring it gracefully handles undefined, null, and invalid values for default dimensions.
• Updated the setDefaultDimensions() method in the Metrics utility to emit a warning when a default dimension is being overwritten.
• Logging a warning if an invalid dimension name or value is provided (i.e., non-string or empty).
• Adding new unit tests to verify the above behaviors, including:
  • Ensuring that calling setDefaultDimensions(undefined) results in immediate return, with no warning emitted and only default dimensions applied.
  • Verifying that invalid dimension values (undefined, null, empty strings) or names are skipped, a warning is emitted in the console, and only valid dimensions are set.

This PR addresses #4134 by improving input validation and error reporting for the setDefaultDimensions method in the Metrics module, to prevent invalid dimension names/values from being set.

Issue number: #4134

Tests Added

The following tests were added:

it('returns immediately if dimensions is undefined', () => {
  // Prepare
  const metrics = new Metrics({
    singleMetric: true,
    namespace: DEFAULT_NAMESPACE,
  });
  // Act
  metrics.setDefaultDimensions(undefined);
  metrics.addMetric('myMetric', MetricUnit.Count, 1);
  // Assess: No warning, only default dimensions/service
  expect(console.warn).not.toHaveBeenCalled();
  expect(console.log).toHaveEmittedEMFWith(
    expect.objectContaining({
      service: 'hello-world',
    })
  );
});

it.each([
  { value: undefined, name: 'valid-name' },
  { value: null, name: 'valid-name' },
  { value: '', name: 'valid-name' },
  { value: 'valid-value', name: '' },
])(
  'skips invalid default dimension values in setDefaultDimensions ($name)',
  ({ value, name }) => {
    // Arrange
    const metrics = new Metrics({
      singleMetric: true,
      namespace: DEFAULT_NAMESPACE,
    });

    // Act
    metrics.setDefaultDimensions({
      validDimension: 'valid',
      [name as string]: value as string,
    });

    metrics.addMetric('test', MetricUnit.Count, 1);
    metrics.publishStoredMetrics();

    // Assert
    expect(console.warn).toHaveBeenCalledWith(
      `The dimension ${name} doesn't meet the requirements and won't be added. Ensure the dimension name and value are non empty strings`
    );

    expect(console.log).toHaveEmittedEMFWith(
      expect.objectContaining({ validDimension: 'valid' })
    );

    expect(console.log).toHaveEmittedEMFWith(
      expect.not.objectContaining({ [name]: value })
    );
  }
);

setDefaultDimensions Update

• Modified to emit a warning if a dimension name or value does not meet requirements (non-empty string).

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

Disclaimer: We value your time and bandwidth. As such, any pull requests created on non-triaged issues might not be successful.