Is there any way to create a HmacSHA256 signature of a string in php?
The hash_hmac() function could help, here :
Generate a keyed hash value using the HMAC method
For example, the following portion of code :
$hash = hash_hmac('sha256', 'hello, world!', 'mykey');
var_dump($hash);
Gives the following output :
string '07a932dd17adc59b49561f33980ec5254688a41f133b8a26e76c611073ade89b' (length=64)
And, to get the list of hashing algorithms that can be used, see hash_algos().