fix(rivetkit): align logs with engine logfmt

[NathanFlurry]

Description

Please include a summary of the changes and the related issue. Please also include relevant motivation and context.

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

Please describe the tests that you ran to verify your changes.

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

[NathanFlurry]

Warning

This pull request is not mergeable via GitHub because a downstack PR is open. Once all requirements are satisfied, merge this PR as a stack on Graphite.
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• chore(rivetkit): note duplicate admission logic #4948
• test(rivetkit): cover bypass fetch header forwarding #4947
• feat(kitchen-sink): add actor probe controls #4946
• fix(gateway): split actor response wait errors #4945
• fix(guard): handle bypass preflight before query parse #4944
• feat(kitchen-sink): add mock agent event log copy #4943
• fix(kitchen-sink): default mock agent to local endpoint #4942
• test(rivetkit): enable driver lifecycle regressions #4941
• test(rivetkit): verify cached websocket db refs exceed grace #4940
• fix(rivetkit-core): keep sleeping actors reachable during grace #4939
• test(rivetkit): cover async websocket close db access #4938
• fix(rivetkit): keep actors awake until keepAwake work finishes #4937
• fix(rivetkit): persist native onSleep state on errors #4936
• fix(rivetkit-core): allow dispatch during sleep grace #4935
• fix(rivetkit): make duplicate sleep requests idempotent #4934
• fix(rivetkit): align logs with engine logfmt #4933 👈 (View in Graphite)
• fix(ci): standardize publish rust toolchain #4931
• SPLIT UP: agentic loop test #4932
• chore(rivetkit): doc skip ready wait #4927
• fix(guard): parse gateway bypass query booleans #4926
• feat(depot-client): add vfs staging cache ttl #4930
• feat(depot-client): wire sqlite optimization flags #4923
• feat(rivetkit): support gateway bypass client overrides #4928
• test(depot-client): stabilize fault harness #4924
• chore(depot-client): split sqlite vfs transports #4922
• feat(rivetkit): support gateway bypass probes #4915
• feat(kitchen-sink): add mock agentic lifecycle loop #4914
• feat(kitchen-sink): add mock agentic loop #4891
• feat(rivetkit): support gateway bypass client requests #4917
• fix(pegboard): restore hibernating request ids #4898 : 2 other dependent PRs (#4899 , #4916 )
• chore(guard): configure local timeout knobs #4913
• docs(rivetkit): raise serverless start payload limit #4911
• test(kitchen-sink): add sqlite memory soak harness #4910
• feat(rivetkit): expose runtime diagnostics #4909
• chore(depot-client): migrate to worker thread #4907 : 2 other dependent PRs (#4912 , #4918 )
• test(driver): select matrix cells with vitest filters #4906
• fix(pegboard): restore hibernating requests on serverful start #4904 : 1 other dependent PR (#4905 )
• fix(rivetkit): drain shutdown work before sleep #4902 : 1 other dependent PR (#4903 )
• feat(sqlite): wire remote sqlite execute handlers #4897
• test(serverless): avoid pinning header validation order #4896
• chore(driver-test-runner): add native/wasm runtime matrix to skill #4884 : 3 other dependent PRs (#4892 , #4894 , #4901 )
• chroe: rename rivetkit-sqlite to depot-client #4883
• fix(rivetkit-wasm): fix mem leaks #4880
• chore(rivetkit): wasm support #4860
• feat(sqlite): add cold read benchmarks and simplify optimizations #4857
• feat(sqlite): benchmark cold reads #4848 : 1 other dependent PR (#4864 )
• docs(actors): document manual lifecycle controls #4847
• test(sqlite): expand db stress coverage #4846 : 1 other dependent PR (#4849 )
• test(raw-websocket): add serverless smoke coverage #4845
• feat(serverless): configure drain grace period #4844
• fix(publish): enable frontend build for engine target and use turbo build instead of turbo build:engine #4843
• feat(rivetkit): expose conn handle in onWebSocket context #4842
• fix(rivetkit): normalize waitUntil/keepAwake promises to null to avoid serde undefined error #4841
• fix(rivetkit): remove requirement for token #4839 : 1 other dependent PR (#4840 )
• fix(pegboard-envoy): allow sqlite requests across lifecycle states #4838
• fix(pegboard): route scoped actor key reads by runner dc #4837
• fix(sqlite-storage): let sqlite open take over stale owners #4834
• fix(engine-tests): parallelize multi-DC startup + enable 6 multi-DC tests #4833
• fix(api): honor cursor in actor_ids list path #4832
• fix(api): silently filter invalid IDs from actor_ids query instead of 400 #4831
• fix(api-peer): make actors_delete idempotent for already-destroyed actors #4830
• fix(pegboard): use Iterator streaming mode in list_names so limit param is honored #4829
• chore(engine-tests): convert envoy tests to Sleep crash policy + triage ignored #4828
• feat(engine-tests): wire envoy actor names through prepopulate_actor_names #4827
• chore(depot): fault injection tests #4868
• feat(sqlite): pitr & forking #4859 : 1 other dependent PR (#4863 )
• chore(sqlite): stateless storage refactor #4856
• main

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[claude]

Code Review: fix(rivetkit): align logs with engine logfmt

Overview

This PR aligns the log format output for the NAPI/TypeScript layers with the engine's logfmt format. It adds logfmt (and GCP/Stackdriver) support on the Rust side via tracing-logfmt / tracing-stackdriver, and implements a custom pino logfmt destination on the TypeScript side.

---

Rust

Generally solid. The conditional layer pattern with Option<SomeLayer> is the idiomatic way to toggle tracing-subscriber layers of different types.

Minor issues:

• env_flag only accepts "1" as truthy. Worth ensuring this is consistent with how the engine reads similar flags.
• RIVET_LOG_TARGET and RUST_LOG_TARGET are OR'd in Rust, but the TypeScript side reads RIVET_LOG_TARGET via getLogTarget() from env-vars.ts and does not use it in the new logfmt destination. Minor asymmetry worth noting.

---

TypeScript

The overall approach (parse pino JSON output, reformat as logfmt) works, but there are correctness and robustness gaps.

Potential bug: incomplete control character escaping in quoteLogfmtString

Only \n is escaped inside quoted strings. \r and \t will be embedded literally, producing multi-line output that breaks downstream log parsers.

Missing flushSync on the destination stream. Pino may call flushSync() on graceful shutdown. Without it, the last log lines before process exit may be lost. A no-op flushSync(): void {} satisfies the interface.

Objects/arrays become opaque JSON strings. formatLogfmtValue falls through to quoteLogfmtString(JSON.stringify(value)) for objects. Functionally correct but less readable than what tracing-logfmt produces on the Rust side. Nice-to-have, not a blocker.

No test coverage. The formatLogfmtLine / quoteLogfmtString / appendLogfmtEntry helpers are pure functions that are easy to unit-test.

---

Summary

Severity	Issue
Bug	quoteLogfmtString does not escape \r/\t and can produce multi-line logfmt output
Minor	No flushSync on pino destination; last lines may be dropped on graceful exit
Minor	env_flag only accepts "1"; may be inconsistent with ops tooling
Nit	RIVET_LOG_TARGET unused in new TS logfmt destination (Rust side checks it)
Suggestion	No unit tests for the logfmt formatting helpers

The control character escaping issue is the only real bug. Everything else is minor. The overall approach is clean and consistent with the engine's logging patterns.

[github-actions]

Preview packages published to npm

Install with:

npm install rivetkit@pr-4933

All packages published as 0.0.0-pr.4933.5484e59 with tag pr-4933.

Engine binary is shipped via @rivetkit/engine-cli on linux-x64-musl, linux-arm64-musl, darwin-x64, and darwin-arm64. Windows users should use the release installer or set RIVET_ENGINE_BINARY.

Docker images:

docker pull rivetdev/engine:slim-5484e59
docker pull rivetdev/engine:full-5484e59

Individual packages

npm install rivetkit@pr-4933
npm install @rivetkit/react@pr-4933
npm install @rivetkit/rivetkit-napi@pr-4933
npm install @rivetkit/workflow-engine@pr-4933

[NathanFlurry]

Landed in main via stack-merge fast-forward push. Commits are in main; closing to match.