The JSONRedirect/JSONOK/JSONError functions were put into "Base" context
incorrectly, it would cause abuse.
Actually, they are for "web context" only, so, move them to the correct
place.
And by the way, use them to simplify old code: +75 -196
1. The "web" package shouldn't depends on "modules/context" package,
instead, let each "web context" register themselves to the "web"
package.
2. The old Init/Free doesn't make sense, so simplify it
* The ctx in "Init(ctx)" is never used, and shouldn't be used that way
* The "Free" is never called and shouldn't be called because the SSPI
instance is shared
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Co-authored-by: Giteabot <teabot@gitea.io>
Replace #16455
Close #21803
Mixing different Gitea contexts together causes some problems:
1. Unable to respond proper content when error occurs, eg: Web should
respond HTML while API should respond JSON
2. Unclear dependency, eg: it's unclear when Context is used in
APIContext, which fields should be initialized, which methods are
necessary.
To make things clear, this PR introduces a Base context, it only
provides basic Req/Resp/Data features.
This PR mainly moves code. There are still many legacy problems and
TODOs in code, leave unrelated changes to future PRs.
