fix(files): count the document body against the export limit

[waleedlatif1]

Follow-up to #5995, from Bugbot's finding on the v0.7.47 release PR (#6005).

Summary

• The 250 MB markdown-export cap measured only the embedded assets' declared sizes. The document body was downloaded with no limit and never counted, so a large document with modest attachments cleared the check and still produced a zip well over the stated limit, materialized whole in memory
• The body is the largest single entry in most bundles, so excluding it left the limit unenforced against the item most able to exceed it
• It is now capped on read and counted alongside its assets, and the message names both

Provenance

#5995 added the asset caps but did not extend them to the body. The unbounded body read predates that PR; what #5995 introduced was an export limit that silently excluded the largest item — so this closes a gap it created rather than an unrelated defect.

Type of Change

• Bug fix

Testing

Two tests added to the suite #5995 introduced: the body counting toward the limit when assets alone sit under it, and the body read carrying the cap. Seven tests on this route pass; lint, check:utils, typecheck and check:api-validation clean.

Checklist

• Code follows project style guidelines
• Self-reviewed my changes
• Tests added/updated and passing
• No new warnings introduced
• I confirm that I have read and agree to the terms outlined in the Contributor License Agreement (CLA)

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1 Skipped Deployment

Project	Deployment	Actions	Updated (UTC)
docs	Skipped		Jul 28, 2026 5:55pm

[cursor]

PR Summary

Medium Risk
Changes bound server memory and rejection behavior on a user-facing export path; scope is limited to size accounting and error mapping, not auth or storage semantics.

Overview
Fixes a gap where the markdown export route only enforced size on embedded assets: the document body was downloaded without a byte cap and excluded from the pre-zip total, so large bodies could pass checks and blow past the stated limit in memory.

The export handler now downloads the markdown with maxBytes set to the same 250 MB total ceiling, treats PayloadSizeLimitError as a 400 with an export-limit message, and sums body + declared asset sizes before fetching attachments (updated error text mentions “document and its embedded files”). The separate 500-embed rejection is removed in favor of the existing upstream MAX_EMBEDDED_IMAGES bound.

Export route tests are extended for body counting, capped reads, and size-limit errors; a new v1 file GET test file documents rendered download behavior (content type, disposition, Content-Length, 409 while compiling, 404).

^{Reviewed by Cursor Bugbot for commit 6950e22. Configure here.}

[greptile-apps]

Greptile Summary

Caps markdown export body size and counts it toward the 250 MB bundle limit.

• Document body download uses maxBytes: MAX_EXPORT_TOTAL_BYTES and maps PayloadSizeLimitError to 400 with an export-limit message.
• Bundle size check is mdBuffer.length plus declared asset sizes, with updated error copy naming document and embeds.
• Removes the local 500-asset count cap (relies on upstream embed bound); adds export tests for body counting, body cap, and body-oversize 400; adds unrelated v1 file download tests.

Confidence Score: 5/5

Safe to merge; the prior body-oversize 500 path is fixed and no blocking failures remain.

Oversized body downloads are caught as PayloadSizeLimitError and returned as 400 with an export-limit message, covered by tests; body bytes are included in the bundle budget with matching coverage.

Important Files Changed

Filename	Overview
apps/sim/app/api/files/export/[id]/route.ts	Body download is capped and size-limited errors return 400; total budget includes body plus assets; asset count cap removed in favor of upstream embed bound.
apps/sim/app/api/files/export/[id]/route.test.ts	Tests body contribution to the limit, maxBytes on the body download, and 400 (not 500) on PayloadSizeLimitError for an oversized body.
apps/sim/app/api/v1/files/[fileId]/route.test.ts	New tests for v1 file download content type, disposition, Content-Length, compile 409, and missing-file 404.

_{Reviews (3): Last reviewed commit: "chore(files): drop the unreachable expor..." | Re-trigger Greptile}

[waleedlatif1]

@greptile

[waleedlatif1]

@cursor review

[cursor]

✅ Bugbot reviewed your changes and found no new issues!

Comment @cursor review or bugbot run to trigger another review on this PR

^{Reviewed by Cursor Bugbot for commit b7f6acd. Configure here.}

[waleedlatif1]

Dropped the export's asset-count cap — it was unreachable.

extractEmbeddedFileRefs stops collecting at MAX_EMBEDDED_IMAGES (50), so imageIds is bounded before this route sees it and a check at 500 could never fire. Its test passed only because it mocked the extractor, so it asserted a branch production cannot reach — worse than no test, since it read as coverage.

The byte ceilings are the real bound and stay. A comment now records where the count is actually enforced so the next reader does not add a second one.

[waleedlatif1]

@greptile

[waleedlatif1]

@cursor review

[cursor]

✅ Bugbot reviewed your changes and found no new issues!

Comment @cursor review or bugbot run to trigger another review on this PR

^{Reviewed by Cursor Bugbot for commit 6950e22. Configure here.}