aerospike_apply.md

Aerospike::apply

Aerospike::apply - Applies a UDF to a record at the Aerospike DB

Description

public int Aerospike::apply ( array $key, string $module, string $function[, array $args [, mixed &$returned [, array $options ]]] )

Aerospike::apply() will apply the UDF module.function to a record with a given key. A list of args can be passed to the UDF and any returned value captured optionally.

Currently the only UDF language supported is Lua. See the UDF Developer Guide on the Aerospike website.

Parameters

key the key under which to store the record. An associative array with keys 'ns','set','key'.

module the name of the UDF module registered against the Aerospike DB.

function the name of the function to be applied to the record.

args an array of arguments for the UDF.

returned if passed will contain the result value (integer, string, array) of calling the UDF.

options including Aerospike::OPT_READ_TIMEOUT, Aerospike::OPT_WRITE_TIMEOUT and Aerospike::OPT_SERIALIZER.

Return Values

Returns an integer status code. Compare to the Aerospike class status constants. When non-zero the Aerospike::error() and Aerospike::errorno() methods can be used.

Examples

Example Record UDF

Registered module my_udf.lua

function startswith(rec, bin_name, prefix)
  if not aerospike:exists(rec) then
    return false
  end
  if not prefix then
    return true
  end
  if not rec[bin_name] then
    return false
  end
  local bin_val = rec[bin_name]
  l = prefix:len()
  if l > bin_val:len() then
    return false
  end
  ret = bin_val:sub(1, l) == prefix
  return ret
end

Example of applying the UDF on a record

<?php

$config = array("hosts"=>array(array("addr"=>"localhost", "port"=>3000)));
$db = new Aerospike($config);
if (!$db->isConnected()) {
   echo "Aerospike failed to connect[{$db->errorno()}]: {$db->error()}\n";
   exit(1);
}

$key = array("ns" => "test", "set" => "users", "key" => "1234");
$res = $db->apply($key, 'my_udf', 'startswith', array('email', 'hey@'), $returned);
if ($res == Aerospike::OK) {
    if ($returned) {
        echo "The email of the user with key {$key['key']} starts with 'hey@'.\n";
    } else {
        echo "The email of the user with key {$key['key']} does not start with 'hey@'.\n";
    }
} elseif ($res == Aerospike::ERR_UDF_NOT_FOUND) {
    echo "The UDF module my_udf.lua was not registered with the Aerospike DB.\n";
} else {
    echo "[{$db->errorno()}] ".$db->error();
}

?>

We expect to see:

The email of the user with key 1234 starts with 'hey@'.