Admin server was crashing silently and requests hang indefinitely.
With this fix, we are now logging the admin server exceptions and also
close the socket afterwards so admin request don't hang.
Signed-off-by: Taimoor Zaeem <taimoorzaeem@gmail.com>
Right now listening sockets initialization, management and usage is split between App, AppState and Admin modules: they are created in AppState.init and remembered in AppState but used only in App and Admin.
It has several negative consequences:
- sockets are initialized even if not needed (eg. command line invocations like dump-config or dump-schema)
- it is impossible to start listening on a socket after initial schema cache load because it requires AppState
This change decouples listen socket management from AppState. Sockets are created only when needed (ie. not in command line tools invocation) and passed to admin application and to Warp by the App module.
Replaces the "API server listening on unix socket" with simpler
"API server listening on " observation. This allows refactoring
redundant code.
Signed-off-by: Taimoor Zaeem <taimoorzaeem@gmail.com>
The prometheus metrics text format requires `Content-Type` header
for correct scraping which fails otherwise. Closes#4271.
Signed-off-by: Taimoor Zaeem <taimoorzaeem@gmail.com>
BREAKING CHANGE
The endpoint was at risk of being left unprotected when exposing it.
The accompanying `admin-server-config-enabled` config was also dropped.
With this:
- Is no longer necessary to pass observer as an argument
to every function that needs observations.
- We can invoke the observer on every function that uses AppConfig.
However it'd be better to just call the observer in the upper modules
(like on App.hs).
This pulls in an updated hlint version from nixpkgs, and fixes some
new eta-reduction warnings. (I don't particularly think this is more
readable, but I suppose being consistently hlint-clean is worth it.)