Build a function
You're still trying to perfect your tools for doing webs scraping to be as efficient as possible doing your job as a data analyst for a web agency.
In this exercise, you will make the extractor function from the previous exercise a little bit stricter: if the code returned by the status extractor is not between 200 and 203, the function will return a missing value (NA
). In the other case, the status code will be returned.
purrr
and httr
have been loaded for you.
This exercise is part of the course
Intermediate Functional Programming with purrr
Exercise instructions
Negate the
%in%
operator, which is used to test if the element on the left is inside the element of the right.Compose a
extract_status()
function, which will be a combination ofGET()
andstatus_code()
.Complete the given function: the
url
status code should be extracted and assigned to acode
variable. Then if thiscode
is not in200:203
, a missing value will be returned. Otherwise, the status code is returned.
Hands-on interactive exercise
Have a go at this exercise by completing this sample code.
# Negate the %in% function
`%not_in%` <- ___(`%in%`)
# Compose a status extractor
extract_status <- ___(___, ___)
# Complete the function definition
strict_code <- function(url) {
# Extract the status of the URL
code <- ___(___)
# If code is not in the acceptable range ...
if (code ___ 200:203) {
# then return NA
return(___)
}
code
}