The Aerospike HHVM client provides access to the Aerospike server via a set of PHP object classes. The objects are implanted as an HNI extension. The Aerospike HHVM client extension is layered on top of the Aerospike C client.
The Aerospike PHP client API is structurally quit similar to the other Aerospike client APIs, especially the Java client API.
PHP array objects are used to describe data structures, such as for specifying a particular object in the database or for the results returned by a request to retrieve that object from the database.
Internally, the PHP API method implementation C function receives an
array object as an input zval argument. The C function first
validates each argument type (to the extent that it can) and the
contents of structured objects. A number of the API methods are
polymorphic, meaning they have different behaviors depending upon
received argument types.
Objects in the Aerospike database are uniquely referenced by a key structure. In the PHP client, keys are specified by an array with three fields: the namespace ("ns"), the set ("set") and the object being used as the name of the object ("key").
For example, to refer to the key key1 in namespace test and set
demo, an array of the following form must be created:
$my_key = array("ns"=>"test", "set"=>"demo", "key"=>"key1");
Each object in the database has metadata described by two integer properties, a generation (or version) and a lifetime (Time To Live, or TTL.)
For example, to define record metadata with a generation of 5 and a TTL of 3600, an array of the following form must be created:
$my_record = array("generation"=>5, "ttl"=>3600);
The Aerospike::getHeader() API return the object's record structure.
The value of an object in the database is comprised of one or more fields, known as "bins", each with a value. Two types of arrays are used to access bins: an array of one or more bin name strings, or an array with elements that are the bin values indexed by bin name.
For example, to refer to the 2 bins "bin1" and "bin3", for example to get their values, an array of the following form must be created:
$my_bins_names = array("bin1", "bin3");
After executing the following API call to get the values,
$rv = $as->get($my_key, $my_bin_names, &$my_bin_values);
an array of the following form would be returned (i.e., as if it were created by the following):
$my_bin_values = array("bin1"=>"value1", "bin3"=>"value3");
PHP strings, integers and associative arrays should map directly to the equivalent types on the database - string, integer, list, and map.
PHP values which do not have a directly mappable bin type need to be handled in a configurable way, whether by calling a specified serializer or by throwing an explicit error.