labels.json is always re-downloaded even if it's the same

[einsteinx2]

I noticed that the script always overwrites the labels/labels.json file for each repo even if the file is the same. This may cause tools like rsync to re-sync those files if you have a script that clones your backups to another machine for example. It also causes a bunch of unnecessary disk writes which always have some--if small--chance of causing data corruption.

Rather than just overwriting these files, the script should compare the file on disk with the file that will be written and only write a new file if the labels have changed.

I'll make and test this change then submit a PR for this soon.

[einsteinx2]

Same issue with the release json files also I think, but need to check. If so, same solution would work.

[josegonzalez]

Sounds good.

[einsteinx2]

Was hoping this would be a single change to the json_dump function but it looks like most places that use it first open a file handle for writing, which from what I read already destroys any existing file. Ironically, the backup_labels function which was the impetus behind creating this issue is the one place that doesn't do that haha. Oh well, still not a big deal, it's only called in 7 places, but looks like I won't be getting this PR in tonight :)

[einsteinx2]

Finished all the code for this yesterday, just need to do some testing then I can make a PR.

[Iamrodos]

I just put in a PR for this change. I am not sure why it did not get summited originally if it was finished. Given @josegonzalez said "Sounds good" I figure this was worth adding. I too prefer that if nothing changes files don't get overwritten with fresh timestamps.

I suspect people using rsync will like this.