Increase unit test coverage

[constanca-m]

Component(s)

pkg/translator/azurelogs

Describe the issue you're reporting

This is an issue that should ideally be done before #39119, if both would move forward.

Currently, some of the unit tests only check a few fields to see if the extraction was successful. Example:

opentelemetry-collector-contrib/pkg/translator/azurelogs/resourcelogs_to_logs_test.go

Lines 687 to 696 in 4e84b33

	func TestAppServiceConsoleLog(t *testing.T) {
	logs, err := loadJSONLogsAndApplySemanticConventions("log-appserviceconsolelogs.json")
	assert.NoError(t, err)
	record := logs.ResourceLogs().At(0).ScopeLogs().At(0).LogRecords().At(0).Body().Map().AsRaw()
	assert.Equal(t, "CONTAINER_ID", record["container.id"])
	assert.Equal(t, "HOST", record["host.id"])
	}

Instead, we could follow a similar approach to what AWS Logs encoding extension does. By using files, we can compare that everything in the logs matches what is expected a bit like this:

opentelemetry-collector-contrib/extension/encoding/awslogsencodingextension/internal/unmarshaler/subscription-filter/subscription_filter_test.go

Lines 135 to 144 in 4e84b33

	logs, err := unmarshalerCW.UnmarshalLogs(test.record)
	if test.expectedErr != "" {
	require.ErrorContains(t, err, test.expectedErr)
	return
	}
	require.NoError(t, err)
	expectedLogs, err := golden.ReadLogs(filepath.Join(filesDirectory, test.logsExpectedFilename))
	require.NoError(t, err)
	require.NoError(t, plogtest.CompareLogs(expectedLogs, logs))

This way we can ensure that any changes done to the code will not affect results, instead of checking that just a few fields won't be changed.

If this change is approved, I volunteer to make these changes.

[github-actions]

Pinging code owners:

• pkg/translator/azurelogs: @atoulme @cparkins @MikeGoldsmith

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[constanca-m]

Please see in my branch main...constanca-m:opentelemetry-collector-contrib:azurelogs-increase-coverage the changes this implies. Every old unit test still works and it is covered by the new unit test TestUnmarshalLogs_Files.

[atoulme]

Sounds good to me!