Support revision #233

[wancom]

As explained #233, some essential feature for revision is not provided.
In next version, we will implement for revision support features.

[wancom]

My current idea is as follows.

Add new APIs.

• For getting old revision data
  GET /doc/:docid/rev/:revision
  docid is terget document uuid and revison is the revision to get.
• For reverting the document to old revision
  PUT /doc/:docid/revert/:revision
  docid is terget document uuid and revision is the revision to revert

Revert function involves OT session stopping to keep consistency.
Revert function may not be necessary.

[0eta0]

how does the revert function work? Is it just replaced a revision document with the latest one?

[wancom]

Yes, that's right.
The function works like copy and paste.

[0eta0]

Thanks, I got it.

[wancom]

@0eta0 Any ideas?

[0eta0]

Is there any function to get a difference of code?

[wancom]

No, there isn't now.
But it's good idea. We need more discussion about this one.

[wancom]

New idea (getting diff) given by @0eta0

For getting diff with current and old version.

• GET /doc/:docid/diff/:revision/:revisionbase
  docid is terget document uuid.
  revison is the revision to compare.
  revisonbase is the revision compared. (If omitted, the current version is used.)

[wancom]

Implemention hint

https://qiita.com/shibukawa/items/dd75ad01e623c4c1166b

[wancom]

I want an idea for data structure.
Can you show me the diff data structure which can handle easily on front?

[wancom]

@0eta0

[0eta0]

Codemirror supports diff viewer, I'm going to use it.
https://codemirror.net/demo/merge.html

[0eta0]

this function will work on the front side.
https://github.com/codemirror/CodeMirror/blob/master/demo/merge.html