[help wanted] Get basic upload-to-wiki working

[BLumia]

Intended to resolve #574 , still WIP, not ready to merge.

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I need this feature and find out there is an issue requesting this feature(#574), so would like to try to implement this feature. I tryed rebasing #6024 onto master but it seems there are too many changes from the codebase so I decided to reimplement the feature directly on master branch. Now the upload works but I do think what I did is probably not the correct way to implement it. I'll explain later.

Here are some WIP screenshots in current PR state:

Screenshots about file upload

Reason about why I think my current implementation is bad is, when try to hacking on this feature, I found temp_repo.go always do operation to the repo when calling NewTemporaryUploadRepository(repo *models.Repository), seems I cannot operate to the wiki repo directly, so I added CloneWiki() and PushWiki() so I can process the wiki repo instead of the original repo. But I found inside PushingEnvironment() there are checks about if it is a wiki repo, so I think I may probably missed something.

The current PR state should be able to upload file to wiki repo, but after clicking the upload button, the page turns blank. I checked the console output and here is the related log:

UploadWikiFilePost
[Macaron] 2020-07-20 16:15:12: Started POST /api/internal/hook/pre-receive/blblb/61616 for [::1]
[Macaron] 2020-07-20 16:15:12: Completed POST /api/internal/hook/pre-receive/blblb/61616 200 OK in 2.9995ms
[Macaron] 2020-07-20 16:15:13: Started POST /api/internal/hook/post-receive/blblb/61616 for [::1]
[Macaron] 2020-07-20 16:15:13: Completed POST /api/internal/hook/post-receive/blblb/61616 500 Internal Server Error in 93.0008ms
[Macaron] 2020-07-20 16:15:13: Completed POST /blblb/61616/wiki/_upload 0  in 2.9386116s
[Macaron] 2020-07-20 16:15:13: Started GET /favicon.ico for 127.0.0.1
[Macaron] 2020-07-20 16:15:13: Completed GET /favicon.ico 304 Not Modified in 1.9981ms
[Macaron] 2020-07-20 16:15:15: Started GET /serviceworker.js for 127.0.0.1
[Macaron] [Static] Serving /serviceworker.js
[Macaron] 2020-07-20 16:15:15: Completed GET /serviceworker.js 304 Not Modified in 33.9743ms

I guess it is the 500 internal server error which caused the issue. I think it probably because I still missed something which cause it trigger the main repo post-receive hock, but still doesn't know where should I look at.

I still not dig into the whole codebase too deep (actually I'm new to golang), but still would like to help implementing this issue. Any advices / comments / code review would be very helpful. Thanks!

[BLumia]

Last commit rebased the code onto the current master and fixed the git hook issue caused by provided a wrong env. There are still one issue haven't get resolved, after clicking the upload button, it will says "The process cannot access the file because it is being used by another process."(the file actually get into the wiki repo, but the cached file not get removed). Still don't know where went wrong..

Anyway although it's still WIP but I think maybe it can be good if someone can review the current state of this PR now so I can know where I did wrong to get me on the right track. Any review and advices are appreciated!

[codecov-commenter]

Codecov Report

Merging #12279 into master will decrease coverage by 0.13%.
The diff coverage is 20.00%.

@@            Coverage Diff             @@
##           master   #12279      +/-   ##
==========================================
- Coverage   43.52%   43.38%   -0.14%     
==========================================
  Files         642      643       +1     
  Lines       71003    71239     +236     
==========================================
+ Hits        30904    30907       +3     
- Misses      35096    35322     +226     
- Partials     5003     5010       +7     

Impacted Files	Coverage Δ
models/helper_environment.go	85.71% <0.00%> (-6.60%)	⬇️
modules/auth/repo_form.go	41.59% <0.00%> (-0.75%)	⬇️
modules/repofiles/upload.go	0.00% <0.00%> (ø)
routers/repo/repo.go	32.28% <0.00%> (-0.26%)	⬇️
routers/repo/wiki.go	37.44% <0.00%> (-3.74%)	⬇️
modules/repofiles/temp_repo.go	60.59% <52.63%> (-1.40%)	⬇️
routers/routes/routes.go	89.02% <100.00%> (+0.12%)	⬆️
services/wiki/wiki.go	56.90% <100.00%> (-1.39%)	⬇️
modules/auth/sso/oauth2.go	46.77% <0.00%> (-14.52%)	⬇️
modules/notification/mail/mail.go	32.50% <0.00%> (-3.75%)	⬇️
... and 28 more

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[stale]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs during the next 2 months. Thank you for your contributions.

[codecov-io]

Codecov Report

Merging #12279 (9869872) into master (ccfa408) will decrease coverage by 0.05%.
The diff coverage is 19.14%.

@@            Coverage Diff             @@
##           master   #12279      +/-   ##
==========================================
- Coverage   42.24%   42.19%   -0.06%     
==========================================
  Files         710      710              
  Lines       77232    77310      +78     
==========================================
- Hits        32626    32618       -8     
- Misses      39241    39317      +76     
- Partials     5365     5375      +10     

Impacted Files	Coverage Δ
models/helper_environment.go	87.50% <0.00%> (-5.84%)	⬇️
modules/auth/repo_form.go	39.16% <0.00%> (-0.67%)	⬇️
modules/repofiles/upload.go	0.00% <0.00%> (ø)
routers/repo/repo.go	32.23% <0.00%> (-0.41%)	⬇️
routers/repo/wiki.go	37.09% <0.00%> (-4.08%)	⬇️
modules/repofiles/temp_repo.go	58.46% <52.63%> (-1.19%)	⬇️
routers/routes/macaron.go	92.60% <100.00%> (+0.06%)	⬆️
services/wiki/wiki.go	57.21% <100.00%> (-1.33%)	⬇️
modules/indexer/stats/queue.go	52.94% <0.00%> (-23.53%)	⬇️
modules/indexer/stats/db.go	43.47% <0.00%> (-8.70%)	⬇️
... and 11 more

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[BLumia]

Due to very limited spare time and the gitea development actually grows pretty fast, I may not have time to continue working on this feature. I'll close this PR and leave the patch here as a reference and see if anyone else would like to work on this feature.

This patch only added a place to upload image files to a _media folder to use, there is no place to browse a list of image files uploaded to the wiki repo. To improve the useability of the wiki feature, I think there are also some other things that need to be done other than just allow uploading image files, but that's more likely a major refactor then :/

Anyway hope the best :)