showReactLog()
options(shiny.reactlog=TRUE)
; then launch your
application in the usual way (e.g. using
runApp
). At any time you can hit Ctrl+F3
(or for Mac users, Command+F3) in your web browser to
launch the reactive log visualization.The reactive log visualization only includes reactive activity up until the time the report was loaded. If you want to see more recent activity, refresh the browser.
Note that Shiny does not distinguish between reactive dependencies that "belong" to one Shiny user session versus another, so the visualization will include all reactive activity that has taken place in the process, not just for a particular application or session.
As an alternative to pressing Ctrl/Command+F3--for
example, if you are using reactives outside of the
context of a Shiny application--you can run the
showReactLog
function, which will generate the
reactive log visualization as a static HTML file and
launch it in your default browser. In this case,
refreshing your browser will not load new activity into
the report; you will need to call showReactLog()
explicitly.
For security and performance reasons, do not enable
shiny.reactlog
in production environments. When
the option is enabled, it's possible for any user of your
app to see at least some of the source code of your
reactive expressions and observers.