RUM-717 feat!: Add network instrumentation for async/await URLSession APIs

[ganeshnj]

What and why?

Fixes #1288

How?

https://datadoghq.atlassian.net/wiki/spaces/RUMP/pages/3130426092

TLDR

Dogfood: https://github.com/DataDog/shopist-ios/pull/55

Customers no longer have to implement Datadog delegate to instrument rather they can simply use high level APIs.

1. Enable URLSessionTracking either via RUM or Trace

RUM.enable()

or

Trace.enable()

2. Enable session tracking per delegate

let delegate = MyDelegate() // implements URLSessionTaskDelegate
URLSessionInstrumentation.enable(with: .init(delegate: delegate))

• instrumentation now works for async-await APIs too.

Review checklist

• Feature or bugfix MUST have appropriate tests (unit, integration)
• Make sure each commit and the PR mention the Issue number or JIRA reference
• Add CHANGELOG entry for user facing changes

Custom CI job configuration (optional)

• Run unit tests
• Run integration tests
• Run smoke tests

[datadog-datadog-prod-us1]

Datadog Report

Branch report: ganeshnj/fix/RUMM-3319-swizzle-urlsessiontask
Commit report: 178a83b

✅ dd-sdk-ios: 0 Failed, 0 New Flaky, 118 Passed, 0 Skipped, 2m 19.45s Wall Time

[ncreated]

Only preliminary feedbacks for now, I need more time 🙏.

[maxep]

Nice work here!

In additions to @ncreated comments, I've left some suggestions. One important topic is delegate instance vs. type when enabling the instrumentation, I think we should be clear that we are instrumenting the class and not the instance.

[maciejburda]

Overall looks good! +1 to other's comments + a few minor ones from my side

[datadog-datadog-prod-us1]

Datadog Report

Branch report: ganeshnj/fix/RUMM-3319-swizzle-urlsessiontask
Commit report: c324433

❌ dd-sdk-ios: 1 Failed (0 Known Flaky), 0 New Flaky, 2289 Passed, 0 Skipped, 5m 17.83s Wall Time

❌ Failed Tests (1)

• testConcurrentBinding - URLSessionDataDelegateSwizzlerTests - Details

  Expand for error

   Abort trap. Check error.crash_log for the full crash log.
  

[ncreated]

Looks neat 👌. I left few questions. On top of it:

• Shouldn't we mark DDURLSessionDelegate as deprecated?
• What about exposing this new API in Objective-C?

[ganeshnj]

Looks neat 👌. I left few questions. On top of it:

• Shouldn't we mark DDURLSessionDelegate as deprecated?
• What about exposing this new API in Objective-C?

Added objc interfaces - good call. Some tests are also updated along with this.

Deprecation - I will handle in seperate PR as it is very specific and shouldn't be coupled.

[maxep]

It looks great!! It's a complex logic but you were able to keep it readable, well done 👍

I've one remaining concern in various swizzler where properties are exposed while a lock is required.

[maciejburda]

Great effort!

One potential blocker on associated object implementation

[ncreated]

Looks good 👌. Solid work 👍. Have we ran unit tests with iOS 12 - 15 Simulators? (to make sure it works and we won't have nightly job problems after merge)

[maxep]

Thank you @ganeshnj for addressing all our comments and questions, it looks great!

[datadog-datadog-prod-us1]

Datadog Report

Branch report: ganeshnj/fix/RUMM-3319-swizzle-urlsessiontask
Commit report: fcbe440

✅ dd-sdk-ios: 0 Failed, 0 New Flaky, 5486 Passed, 0 Skipped, 29m 43.75s Wall Time

[datadog-datadog-prod-us1]

Datadog Report

Branch report: ganeshnj/fix/RUMM-3319-swizzle-urlsessiontask
Commit report: 97deb72

✅ dd-sdk-ios: 0 Failed, 0 New Flaky, 2659 Passed, 0 Skipped, 30m 19.31s Wall Time

[maxep]

🚀

[maciejburda]

LGTM

[datadog-datadog-prod-us1]

Datadog Report

Branch report: ganeshnj/fix/RUMM-3319-swizzle-urlsessiontask
Commit report: 0b56eb5

✅ dd-sdk-ios: 0 Failed, 0 New Flaky, 2697 Passed, 0 Skipped, 28m 1.83s Wall Time

[maxep]

🚀