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5. Query string

Available inall subroutines.

Returns the given URL with its query string sorted. For example, querystring.sort("/foo?b=1&a=2&c=3"); returns "/foo?a=2&b=1&c=3".

Passing in true to the only_unique_keys parameter will filter out non-unique keys from the query string parameters. For instance, querystring.sort("/test?a=7&a=2&a=1&b=5&b=3", true) yields "/test?a=7&b=5".

Some additional behaviors to note:

• If there are more than 32 parameters, the URL is left unsorted.
• Sorting is case-sensitive, with uppercase coming before lowercase (e.g., "A" sorts before "a").
• All parameters are preserved by default, even with duplicate keys or duplicate values.
• Empty parameters with no key will be dropped.

Example

set req.url = querystring.sort(req.url);
set req.url = querystring.sort(req.url, true);

Try it out

querystring.sort 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.