Issue passing non-string as a key

When passing a non-string as the key to any CRUD operation (insert, upsert or get) the return value is

 array(0) { } 

.

This seems incorrect to me, there should be some sort of error returned within a CouchbaseMetaDoc, which is the expected output which specifies why the operation failed.

Alternatively, if a string must be used for the key, then the SDK should try and convert the value passed to it to a string before performing the operation.

Example code to reproduce:

<?php

$cluster = new CouchbaseCluster('http://localhost:8091');

$bucket = $cluster->openBucket('default');

for ($i = 1; $i <= 10000; $i++) {

  $result = $bucket->upsert($i, '');

  var_dump($result);

}

This returns 10000 of the following:

array(0) {

}

When the key is converted to a string before being passed to the SDK, there is no issue.

Example:

<?php

$cluster = new CouchbaseCluster('http://localhost:8091');

$bucket = $cluster->openBucket('default');

for ($i = 1; $i <= 10000; $i++) {

  $result = $bucket->upsert("$i", '');

  var_dump($result);

}

Output:

object(CouchbaseMetaDoc)#4 (4) {

  ["error"]=>

  NULL

  ["value"]=>

  string(0) ""

  ["flags"]=>

  int(0)

  ["cas"]=>

  resource(10002) of type (CouchbaseCAS)

}