fix(sandbox): make daemon.json read async to stop blocking the event loop - #5336
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…loop readConfig() used readFileSync on the daemon's single-threaded Bun event loop. It runs from orchestrator.fillApplicationDefaults() during stepClone — a live-daemon path, not just boot — so every clone blocked the loop from answering its HTTP health probe for the duration of the read. Studio tears down a daemon on a single missed probe. Switch to node:fs/promises readFile and thread the await through both call sites (entry.ts hydrate, orchestrator.ts fillApplicationDefaults).
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PR: #5336 fix(sandbox): make daemon.json read async to stop blocking the event loop Bump type: patch - @decocms/sandbox (packages/sandbox/package.json): 1.24.3 -> 1.24.4 - deploy/helm/sandbox-env (chart 0.9.35) (deploy/helm/sandbox-env/values.yaml deploy/helm/sandbox-env/Chart.yaml): image.tag/appVersion -> 1.24.4 Deploy-Scope: both
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Source: hardening follow-up — CONTRIBUTING.md rule #1 / CLAUDE.md gotcha #8 explicitly bans sync fs in
packages/sandbox/daemon/**because the daemon runs on a single-threaded Bun event loop and Studio tears the daemon down on a single missed health-probe response.Why it matters:
persistence.ts#readConfigusedreadFileSyncto load.decocms/daemon.json. It's not just a boot-time call —orchestrator.ts#fillApplicationDefaultscalls it duringstepClone, which runs on an already-serving daemon, so every repo clone blocked the event loop (and the health probe) for the duration of that synchronous read.Fix: switched
readConfigtonode:fs/promisesreadFileand made itasync, threadingawaitthrough both call sites (entry.ts'shydrate(), now itself async with a top-levelawait, andorchestrator.ts'sfillApplicationDefaults). Pure behavior-preserving conversion — same validation, same return shape, same error handling — just non-blocking. Updatedpersistence.test.tsto use the asyncnode:fs/promiseshelpers andawait readConfig(...).Reviewer check:
cd packages/sandbox && bunx tsc --noEmitandbun test packages/sandbox/daemon/persistence.test.ts.Verified locally:
bun run fmt,bunx tsc --noEmitinpackages/sandbox(green), and the targetedpersistence.test.ts(3 pass). Full CI covers the rest.Summary by cubic
Make reading
.decocms/daemon.jsonasync to stop blocking the daemon’s Bun event loop and prevent missed health probes during repo clones. Behavior is unchanged; the read is now non-blocking.readConfigtonode:fs/promises.readFileand made it async.awaittoentry.tshydrate()(top-levelawait) andsetup/orchestrator.tsfillApplicationDefaults().persistence.test.tsto asyncfsAPIs andawait readConfig.Written for commit 1284562. Summary will update on new commits.