- Moved (in|de)crementBusyCount calls out of Context and into Observer
- decrementBusyCount is (effectively) deferred for async observers until
the async operation is complete
- invalidateLater didn't force(session), almost certainly was buggy
- invalidateLater, reactiveTimer, and manageInputs all now use a new
session$cycleStartAction, which delays their effect until observers
(including async ones) are done executing
* style & formatting. fixes#1859
* prepare `choices` in `updateSelectizeInput()` as per discussion in #1861
* remove duplicated block in selectizeJSON, simply `lab` assignement logic
* Fix#1824: HEAD request on static files causes app to stop
The problem was that for HEAD requests specifically, we implement
an explicit Content-Length header (normally we let httpuv figure
out the Content-Length based on the content, but for HEAD we don't
return any content but still want to include the Content-Length).
The Content-Length header was only implemented correctly for string
values, not for raw vectors or file-by-path. This change implements
the value correctly for all currently valid httpuv content.
* Update NEWS
* Code review feedback
* NEWS item
* added `onStop` arg to `shinyApp()` (and renamed our internal `onEnd` - which is what was calling `on.exit()` already - to `onStop` as well)
* added onStop() function
* add entry for documentation
* make it work for all possible app structures (interactive, saved as app.R, saved as ui.R and server.R)
* fix#1772: make sure `onStart` works in all scenarios
* update NEWS
* improved wording
* more wording
* and more wording
* don't stop execution if a `onStop` callback function results in an error
* remove "(all sessions have been disconnected)" because it's misleading
* add @seealso documentation
* shamefully forgot to Cmd Shift D
* change code place
* Code review feedback
* onStop: use session argument instead of scope
