Helper class to simplify generating a signature for APIs that use HMAC, such as APIs using ApiAxle.
This uses a given shared secret to calculate a signature for a given API key prepended with the current unix timestamp. A different timestamp can optionally be specified, as can a particular hashing algorithm if something other than the default (SHA1) is desired.
The expected common usage:
$signature = \CalcApiSig\HmacSigner::CalcApiSig('api key', 'shared secret');
A more rare usage, in which the time used is 2 seconds in the future (perhaps to compensate for excessive latency) and the desired hashing algorithm is MD5:
$signature = \CalcApiSig\HmacSigner::CalcApiSig( 'api key', 'shared secret', time() + 2, 'md5' );
Calc API Sig is licensed under the MIT license. See "LICENSE" for details.