Throw an exception when trying to add element to nonexistent index?

[smoskalenko]

Hi @raphaelstolt

Thanks for your library, I think it's best library for patching JSONs on github ;) But we want to have another feature in our project - we want to catch the cases when someone trying to add element to array to nonexistent index, as example case with too large index in patch operation:

$inputArray = [
  'arrayField' => ['foo', 'bar', 'baz']
];

$jsonPatch = [
  ['op' => 'add', 'path' => '/arrayField/7', 'value' => 'new']
];

What are you thinking about throwing exception in such cases in Rs/Json/Patch/Operations/Add::perform() method, so we can catch this and process as we want. Can I create pull request for this feature?

Best regards,
Slava

[raphaelstolt]

Hi @smoskalenko, how about performing a test operation prior to using one of the patch (i.e. add) methods?

[smoskalenko]

Hi @raphaelstolt

Do you mean that before main patch request we should run test operation and check that array field contains specified index?

Also I've played a little bit with test operation and found the following issue:

$inputData =  json_encode( 
  [
    'arrayField' => [
        ['name' => 'foo'],
        ['name' => 'bar']
    ]
  ]
);
$jsonPatch = json_encode(
    [
        ['op' => 'test', 'path' => '/arrayField/0', 'value' => ['name' => 'foo']]
    ]
);

// Apply JSON patches
$patch = new Patch($inputData, $jsonPatch);
$patchedDocument = $patch->apply();

I get the FailedTestException("Failed on Test PatchOperation at index: 0")

It seems that new integration test is needed.

The basic issue is that in unit tests you instantiate the operation objects with the following structure (value is json encoded string, why?):

$operation = new \stdClass;
$operation->path = '/chars/array';
$operation->value = '["abc", "def"]';

$testOperation = new Test($operation);

But in fact when we call patch() operations objects instantiate with stdObject where value also is stdObject in case of array (because of json_decode() convert assoc. array to std object, when calling without $assoc flag).

object(stdClass)#239 (3) {
  ["op"]=>
  string(4) "test"
  ["path"]=>
  string(13) "/arrayField/0"
  ["value"]=>
  object(stdClass)#238 (1) {
    ["name"]=>
    string(3) "foo"
  }
}

P.S. In our application in most cases we have a big JSON documents, and patch request will consist of a several operations, so it's very comfortably just send PATCH request to REST API for-example and get the result - 200 OK , or 400 Bad Request