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Available inall subroutines.

Returns a SHA-256-based message authentication code based on the supplied key and string s. The returned code is Base64-encoded.

Example

declare local var.hmac_sha256_base64 STRING;
set var.hmac_sha256_base64 = digest.hmac_sha256_base64("key", "input");
# var.hmac_sha256_base64 is now "ngiewTr4gaisInpzbD58SQ6jtK/KDF+D3/Y5O2g6cuM="

Try it out

digest.hmac_sha256_base64 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.