Module ngx_stream_split_clients_module

The ngx_stream_split_clients_module module (1.11.3) creates variables suitable for A/B testing, also known as split testing.

stream {
    ...
    split_clients "${remote_addr}AAA" $upstream {
                  0.5%                feature_test1;
                  2.0%                feature_test2;
                  *                   production;
    }

    server {
        ...
        proxy_pass $upstream;
    }
}

Creates a variable for A/B testing, for example:

split_clients "${remote_addr}AAA" $variant {
               0.5%               .one;
               2.0%               .two;
               *                  "";
}

The value of the original string is hashed using MurmurHash2. In the example given, hash values from 0 to 21474835 (0.5%) correspond to the value ".one" of the $variant variable, hash values from 21474836 to 107374180 (2%) correspond to the value ".two", and hash values from 107374181 to 4294967295 correspond to the value "" (an empty string).