accept.language_lookup
Available inall subroutines.
Selects the best match from a string in the format of an Accept-Language
header's value in the listed languages using the algorithm described in
RFC 4647, Section 3.4.
This function takes the following parameters:
- a colon-separated list of languages available for the resource,
- a fallback return value,
- a string representing an
Accept-Language
header's value.
This function conforms to RFC 4647.
Example
set bereq.http.Accept-Language = accept.language_lookup("en:de:fr:nl", "en", req.http.Accept-Language);
Try it out
accept.language_lookup
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.
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