fix(parser): CloudWatch Log Envelope handles non-JSON

[dreamorosi]

Summary

Changes

Please provide a summary of what's being changed

This PR fixes theCloudWatchEnvelope built-in envelope so that it correctly handles log messages that are not JSON strings. The previous implementation forced the parsing to always attempt a JSON.parse which would fail in the case of non-JSON-structured log messages.

For example, parsing a series of log messages from an AWS Lambda function invocation would fail when encountering messages like this:

{
  "id": "38569604798453153764115268074363468419149517103543812096",
  "timestamp": 1729520895158,
  "message": "2024-10-21T14:28:15.158Z\teadc91c8-8273-4a2d-b170-b0a7883b619e\tINFO\tHello from other.ts\n"
},
{
  "id": "38569604798453153764115268074363468419149517103543812097",
  "timestamp": 1729520895158,
  "message": "START RequestId: eadc91c8-8273-4a2d-b170-b0a7883b619e Version: $LATEST\n"
},
{
  "id": "38569604798475454509313798697505004137422165465049792514",
  "timestamp": 1729520895159,
  "message": "{\"level\":\"INFO\",\"message\":\"Hello from other.ts\",\"sampling_rate\":0,\"service\":\"service_undefined\",\"timestamp\":\"2024-10-21T14:28:15.158Z\",\"xray_trace_id\":\"1-671664ff-69b0ec7624423e04544c023f\"}\n"
},

This PR fixes this behavior by removing the forced JSON parsing and instead letting the customer set the parsing if they know their message is JSON-structured, i.e.

const result = CloudWatchEnvelope.safeParse(
  event,
  JSONStringified(
    z.object({
      level: z.string(),
      message: z.string(),
      sample_rate: z.number(),
    })
  )
);

The PR also refactored the unit tests for both the schema & the envelope, as well as removing the usage of Envelope in favor of an implementation in the CloudWatchEnvelope that now includes the correct full path in the error, i.e.

new ParseError(
  'Failed to parse CloudWatch Log message at index 0', // works also for multiple indexes
  {
    cause: new ZodError([
      {
        code: 'custom',
        message: 'Invalid JSON',
        path: ['awslogs', 'data', 'logEvents', 0, 'message'],
      },
    ]),
  }
)

The PR also adds a new custom error that is thrown when either the unzip or decode operations fail, since the error thrown by the standard library is rather opaque and a generic Error.

While working on this PR I also removed another batch of test event files that were not used nor referenced anywhere.

Please add the issue number below, if no issue is present the PR might get blocked and not be reviewed

Issue number: fixes #3225

---

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.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
4.0% Duplication on New Code

See analysis details on SonarQube Cloud

[am29d]

Minor qustion on why we deleted other events that has nothing to do with CloudWatch.