Available in all subroutines.
Returns the given URL with the given parameter
name set to the given
replacing the original value and removing any duplicates. If the parameter
is not present in the query string, the parameter will be appended with
the given value to the end of the query string. The parameter
will be URL-encoded when set in the query string.
set req.url = querystring.set(req.url, "foo", "baz");
Try it out
querystring.set is used in the following code examples. Examples apply VCL to real-world use cases and can be deployed as they are, or adapted for your own service. See the full list of code examples for more inspiration.
Click RUN on a sample below to provision a Fastly service, execute the code on Fastly, and see how the function behaves.
Improve cache performance by normalizing requests. Filter and reorder query params, convert to lowercase, filter headers, and more.