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crul (version 1.5.0)

hooks: Event Hooks

Description

Trigger functions to run on requests and/or responses. See Details for more.

Arguments

Details

Functions passed to request are run before the request occurs. The meaning of triggering a function on the request is that you can do things to the request object.

Functions passed to response are run once the request is done, and the response object is created. The meaning of triggering a function on the response is to do things on the response object.

The above for request and response applies the same whether you make real HTTP requests or mock with webmockr.

Examples

Run this code
if (FALSE) {
# hooks on the request
fun_req <- function(request) {
  cat(paste0("Requesting: ", request$url$url), sep = "\n")
}
(x <- HttpClient$new(url = "https://hb.opencpu.org",
  hooks = list(request = fun_req)))
x$hooks
x$hooks$request
r1 <- x$get('get')

captured_req <- list()
fun_req2 <- function(request) {
  cat("Capturing Request", sep = "\n")
  captured_req <<- request
}
(x <- HttpClient$new(url = "https://hb.opencpu.org",
  hooks = list(request = fun_req2)))
x$hooks
x$hooks$request
r1 <- x$get('get')
captured_req



# hooks on the response
fun_resp <- function(response) {
  cat(paste0("status_code: ", response$status_code), sep = "\n")
}
(x <- HttpClient$new(url = "https://hb.opencpu.org",
  hooks = list(response = fun_resp)))
x$url
x$hooks
r1 <- x$get('get')

# both
(x <- HttpClient$new(url = "https://hb.opencpu.org",
  hooks = list(request = fun_req, response = fun_resp)))
x$get("get")
}

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