fix(dart): derive InputFile filename from path

[abnegate]

Summary

Uploads over 5 MB from the Flutter and Dart SDKs fail with storage_file_empty / "Empty file passed to the endpoint." whenever the caller uses InputFile.fromPath(path: ...) without passing filename:. Files at or under 5 MB upload fine, which is what makes it look like a chunking problem.

It isn't. The SDK chunks correctly. The two upload paths just build the multipart part differently:

Size	Path	content-disposition sent
≤ 5 MB	MultipartFile.fromPath(...)	name="file"; filename="video.mp4"
> 5 MB	MultipartFile.fromBytes(..., filename: file.filename)	name="file"

InputFile.fromPath leaves filename null when the caller omits it. package:http's IO helper does filename ??= segments.last, so the single-request path always ends up with a filename, while fromBytes passes the null straight through and package:http emits the attribute only if (file.filename != null).

A multipart part with no filename is not a file upload. Swoole puts it in $request->post, so $request->getFiles('file') returns [] and Create.php throws STORAGE_FILE_EMPTY. Every chunk is rejected.

Fix

Derive the filename from the path at construction, the same way package:http already does for MultipartFile.fromPath, so both upload paths send an identical part. Dart and Flutter share this template, so one change covers both SDKs. A path with no final segment (/path/to/) still leaves filename null, so nothing starts sending filename="".

Verification

Driving the real generated SDK at a Swoole server that reproduces Appwrite's getFiles('file') check, uploading 12 MB via InputFile.fromPath(path: ...) with no filename:

Before:

RESULT: upload FAILED -> storage_file_empty: Empty file passed to the endpoint.
server: CHUNK REJECTED: no file part (landed in post: fileId,file)

After:

progress 42%  chunk 1/3
progress 83%  chunk 2/3
progress 100% chunk 3/3
RESULT: upload SUCCEEDED, name="holiday-video.mp4"
server: CHUNK OK: name=holiday-video.mp4 size=5242880 range=bytes 0-5242879/12582912
        CHUNK OK: name=holiday-video.mp4 size=5242880 range=bytes 5242880-10485759/12582912
        CHUNK OK: name=holiday-video.mp4 size=2097152 range=bytes 10485760-12582911/12582912

The unit tests were also seen red against the pre-fix template, failing on exactly the null filename:

InputFile creates InputFile from path [E]                        Expected: 'file'      Actual: <null>
InputFile derives filename from path when none is given [E]      Expected: 'video.mp4' Actual: <null>
InputFile derives filename from path on the deprecated ctor [E]  Expected: 'video.mp4' Actual: <null>

Generation suite: 87 passed, 4 skipped. lint-twig: 586 files, 0 errors. Generated Dart SDK passes dart analyze with no issues.

Notes

• The existing test asserted expect(inputFile.filename, isNull), which pinned the broken behaviour. It is updated rather than removed.
• Flutter Web is unaffected: InputFile.fromBytes already requires a filename.
• Present since 2022-06-14, so shipped SDKs need a release to pick this up. Until then the workaround is to pass filename: explicitly.
• There is no E2E test covering the chunked upload path in this repo; the verification above was run by hand against a real Swoole parser.
• composer lint (phpcs) reports 219 pre-existing errors across 21 PHP files on main. This PR changes no PHP and leaves them alone.

🤖 Generated with Claude Code

[greptile-apps]

Confidence Score: 5/5

The PR appears safe to merge; the observable multipart regression is covered and no outstanding correctness issue remains.

Summary

This PR derives a Dart InputFile filename from its path so chunked multipart uploads include the required filename attribute, and adds generated-SDK coverage of that behavior.

• Preserves explicitly supplied filenames and leaves paths without a final segment unresolved.
• Registers a Dart multipart integration test that exercises more than one chunk.
• Revises the chunk test to avoid asserting an exact chunk count while checking every received part.

_{Reviews (3) · Last reviewed commit: "test(dart): assert chunk filenames witho..."}