Make generated ids unique across processes

[AjayThorve]

Problem

runtime_id (and invocation_id, plus the artifact roots derived from them) can collide between two concurrent runs on the process-backed path. smoke_sdk_concurrency fails intermittently — ~3/12 runs in a local baseline.

Root cause

new_id builds ids from a millisecond timestamp + a process-global AtomicU64 counter:

let counter = NEXT_ID.fetch_add(1, Ordering::Relaxed);
format!("{prefix}-{}-{counter}", now_millis())

The counter only differentiates ids within one process. A process-backed runner (FabricClient(command=("cargo","run",…))) spawns a fresh fabric-cli per call, so the counter resets to 1 every time. Two concurrent runs in the same millisecond both produce …-<millis>-1 → collision.

Fix

Include std::process::id(), which the OS keeps distinct across concurrently running processes, so ids stay unique across processes too. new_id is the single source for request/environment/runtime/invocation/event ids, so one change covers all. No new dependency.

Verification

• smoke_sdk_concurrency: 3/12 fail before → 0/20 after.
• cargo test --workspace green; smoke_cli / smoke_sdk / smoke_native_sdk pass (ids feed artifact dir names).
• ids are opaque (nothing in the tree parses them by -).

Follow-up

Once this and the CI PR (#8) both land, smoke_sdk_concurrency can be re-added to ci_python.yml (it's excluded there only because of this flake).

Summary by CodeRabbit

• Bug Fixes
  • Enhanced ID generation to ensure uniqueness across concurrent processes.

[coderabbitai]

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ℹ️ Recent review info

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Plan: Enterprise

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📥 Commits

Reviewing files that changed from the base of the PR and between 7c9b0c1 and 09e7281.

📒 Files selected for processing (1)

• crates/fabric-core/src/runtime.rs

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📝 Walkthrough

Walkthrough

The new_id helper in crates/fabric-core/src/runtime.rs now includes the current OS process ID in the generated identifier string, changing the format from prefix-<millis>-<counter> to prefix-<millis>-<pid>-<counter>.

Changes

Process ID in ID Generation

Layer / File(s)	Summary
Include PID in new_id format crates/fabric-core/src/runtime.rs	new_id now calls std::process::id() and embeds it between the timestamp and atomic counter in the formatted ID string; comments are updated to match.

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~2 minutes

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title accurately summarizes the main change: updating the ID generation function to include process ID, making generated IDs unique across concurrent processes.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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✨ Finishing Touches

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