refactor: simplify file adding

[hacdias]

@lidel with your comment yesterday (#762 (comment)) I ended up changing the code and simplifying it a bit.

Although, it happened once or twice to upload like 10 streams and it would only return 1 hash which I think it might be related to https://github.com/ipfs/js-ipfs-api/issues/797!

It also happened before, but since it was only one by one, they wouldn't all fail.

License: MIT
Signed-off-by: Henrique Dias [email protected]

[hacdias]

Fact is: the same set of files errors when using go-ipfs, but it always works on js-ipfs.

[lidel]

LGTM!

Tested:

• adding multiple files (flat)
• adding a directory with multiple levels of subdirs (350MB tree of mp3 and flac from Jamendo)

[lidel]

@hacdias

FYI IPFS Companion already applies a fix for ipfs/js-ipfs-api#797 with local node under Firefox, but Chrome does not allow us to touch Connection header so we should have additional error handling for Chrome users.

There should be an additional check to avoid silent failures (but it can be separate PR):

1. count the number of added items
2. count the number of results returned by files.add (+1 if wrapping dir)
3. if counts do not match, do not copy results to MFS, but display error message
   • I dont think users care about details of ipfs/js-ipfs-api#797, so it should say something simple and actionable like "Unable to finish upload: IPFS API returned a partial response. Try adding a smaller tree." (should heal most failures, if user adds different set of bytes the bug will probably go away).

[hacdias]

@lidel thanks! Just added it here!