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Exercise

Extracting status codes with GET()

For this last exercise, we'll switch from the read_lines() function to the GET() function from httr.

We'll first create a possibly() version of GET(), in order to test if some of the URLs you've got return an error. If you can access the URL, a connection object will be returned. In it, you'll find a "status_code" element.

Don't focus on the results, just remember that if a GET() function returns an error, it's because the URL is not available. The status code number we are returning can appear a bit like web jargon, but we'll talk about it with more depth in the next chapter. Just remember, for now, that 200 means everything went as expected.

The urls vector is available in your workspace, purrr and httr has been loaded for you.

Instructions

100 XP

  • Create a version of GET() that would return NULL in case of error.

  • Set the names of the results.

  • Remove the NULL.

  • Extract the "status_code" of each element.