req_error {httr2} | R Documentation |
req_perform()
will automatically convert HTTP errors (i.e. any 4xx or 5xx
status code) into R errors. Use req_error()
to either override the
defaults, or extract additional information from the response that would
be useful to expose to the user.
req_error(req, is_error = NULL, body = NULL)
req |
A request. |
is_error |
A predicate function that takes a single argument (the
response) and returns |
body |
A callback function that takes a single argument (the response)
and returns a character vector of additional information to include in the
body of the error. This vector is passed along to the |
A modified HTTP request.
req_retry()
to control when errors are automatically retried.
# Performing this request usually generates an error because httr2
# converts HTTP errors into R errors:
req <- request("http://httpbin.org/404")
try(req %>% req_perform())
# You can still retrieve it with last_response()
last_response()
# But you might want to suppress this behaviour:
resp <- req %>%
req_error(is_error = function(resp) FALSE) %>%
req_perform()
resp
# Or perhaps you're working with a server that routinely uses the
# wrong HTTP error codes only 500s are really errors
request("http://example.com") %>%
req_error(is_error = function(resp) resp_status(resp) == 500)
# Most typically you'll use req_error() to add additional information
# extracted from the response body (or sometimes header):
error_body <- function(resp) {
resp_body_json(resp)$error
}
request("http://example.com") %>%
req_error(body = error_body)
# Learn more in https://httr2.r-lib.org/articles/wrapping-apis.html