Empty documents not handled correctly, can lead to failed PUTs

[darkdread]

This line in the codebase causes issue if the body is 0 byte; it will skip the storing of revision (etag) and subsequent pushes to the server will fail due to etag mismatch.

The correct behavior I can think of are:

1. Keep the current behavior, but the remotestorage client MUST store 0 byte document properly
2. Accept 0 byte document, but allow PUT with/without etag (treat as empty)
3. Disallow 0 byte document at all

Maybe this issue should be referenced in https://github.com/remotestorage/spec/issues?

[raucao]

Good catch!

I just looked into the behavior there. It does succeed in updating a document in the same window/session where it was created, but it fails when receiving an empty document from the remote and then trying to update.

Maybe this issue should be referenced in https://github.com/remotestorage/spec/issues?

Yes, this is indeed also a question for the spec. I think the likely answer will be that it is allowed and nothing has to be changed. Otherwise it would be a breaking change and potentially require migration if anyone ever stored empty documents for some reason.

Servers should also not make exceptions for conditional requests, i.e. they should not ignore conditions if given. It's the responsibility of the client to send correct requests.

[raucao]

@darkdread The line you found only applies when there's a conflict. But then it's also a bug, because the body is already not undefined as per the check above. The culprit for non-conflict cases is this one, which is the same bug, just elsewhere:

remotestorage.js/src/sync.ts

Lines 569 to 571 in 1a8d3f9

	if (!node.remote.body) { // no remote, so delete/don't create
	return;
	}

Fix incoming.