Need some help to direct http based-on IP and uri

It should work (after minor syntactic cleanup). It can be streamlined somewhat:

class allowed {
   host 172.10.10.3
   host 192.168.20.15
}
rule access {
   if (client_addr equals one of allowed and http_uri starts_with "/access")  {
     if (client_addr == 192.168.20.15 and http_uri contains "/secureview")   
     {
       discard
     }
     else {
       use pool pool1
     }
   } else {
     discard
   }
}

Using the class and the one of operator is especially useful if there are many addresses to test against. In your case in does not make much difference.