Save 3.0 project JSON to the project server and assets to the assets server

[rschamp]

Depends on scratchfoundation/scratch-vm#1750. Tests will fail until that PR is merged and this PR is bumped to the new version of the VM.

Known issues to be addressed in a follow-up:

• Handle failed asset and project json uploads (When saving fails, detect error and respond appropriately #3723)
• Auto-saving (Autosave on an interval when a user is editing a project they own #3181)
• Dirty- (or clean-)state tracking of the project JSON

Resolves

What Github issue does this resolve (please include link)?

• Resolves Mark saved assets as "not dirty" after saving them scratch-vm#1578

Proposed Changes

Describe what this Pull Request does
Stop saving .sb3 files to the project server, and begin saving assets to the asset server and a project JSON file to the project server.

After assets are saved, mark them as "clean", and only save assets without this "clean" flag. This causes assets not to be saved multiple times unnecessarily.

Also, re-save the default costumes for the cat sprite. Because of line ending settings in Git, these files had diverged from their md5. To avoid this issue going forward, I set .gitattributes to consider all .svg files as binary, so git wouldn't worry about line endings in them.

Reason for Changes

Explain why these changes should be made
We want to save flat JSON files rather than zip files to the project server, and dedupe assets on the asset server. This also moves us closer to being able to track the project dirty state.

Test Coverage

Please show how you have added tests to cover your changes
Existing tests will pass, pending bumping the scratch-vm dependency above.

Browser Coverage

Check the OS/browser combinations tested (At least 2)

Mac

• Chrome
• Firefox
• Safari

Windows

• Chrome
• Firefox
• Edge

Chromebook

• Chrome

iPad

• Safari

Android Tablet

• Chrome

[benjiwheeler]

I can't seem to try this out without causing errors:

Uncaught TypeError: Cannot read property 'click' of undefined
    at SBFileUploader.handleClick (webpack:///../scratch-gui/dist/scratch-gui.js?:293736)

gui Unhandled Error: Error: A cross-origin error was thrown. React doesn't have access to the actual error object in development. See https://fb.me/react-crossorigin-error for more information.    at Object.invokeGuardedCallbackDev (webpack:///./~/react-dom/cjs/react-dom.development.js?:588:19)

What I'm doing:

1. edit project I own
2. click on the File menu

[benjiwheeler]

Tests are failing -- looks like project-saver-hoc

BTW I reran them in case it was just a passing problem

[rschamp]

Tests will fail until the VM PR is merged and updated here. This depends on vm.assets, which won't exist until that's merged.

The cross-origin error is usually a secondary error from a 500 (or some other error) response, which don't have CORS headers set on it. Can you check out the network tab? Maybe your local API or projects servers need to get updated?

[rschamp]

@benjiwheeler I just realized I forgot to push and make a PR for the assets server, which needs updating for this to work. That's probably your CORS issue, sorry!

[benjiwheeler]

Got this to run without crashing, using that -assets PR!

How else should I test it? It saves without crashing after I mess around with costumes... anything else I can try?

[rschamp]

@benjiwheeler Let's follow up on the comment. I would like this in for the freeze.