start_vignette() to either use previously recorded responses, if they
exist, or capture real responses for future use.
start_vignette(path, ...) end_vignette()
Root file path for the mocks for this vignette. A good idea is to use the file name of the vignette itself.
Optional arguments passed to
Nothing; called for its side effect of starting/ending response recording or mocking.
In a vignette or other R Markdown or Sweave document, place
start_vignette() in an R code block at the beginning,
before the first API request is made, and put
end_vignette() in a R code chunk at the end. You may
want to make those R code chunks have
echo=FALSE in order to hide the fact
that you're calling them.
The behavior changes based on the existence of the
path directory. The
first time you build the vignette, the directory won't exist yet, so it will
make real requests and record them inside of
path. On subsequent runs, the
mocks will be used. To record fresh responses from the server, delete the
path directory, and the responses will be recorded again the next time the
If you have additional setup code that you'd like available across all of
your package's vignettes, put it in
inst/httptest/start-vignette.R in your
package, and it will be called in
start_vignette() before the mock/record
context is set. Similarly, teardown code can go in
inst/httptest/end-vignette.R, evaluated in
end_vignette() after mocking