Problems with multi-valued fields

Services just calls drupal_submit so the issue is likely with your data structure.

So I did a quick google and came up with http://drupal.org/node/1066786, so it seems like you are correct about the ajax part, and it is actually a core bug. You might be able to define a hook_form_alter to increment the field item count in question?

This is won't fix for services.

Hi, I am stuck up simillar kind of situation. I have field colletion with multiple value and I am not able to submit 2 value through service API. Can you please let me know how you overcome your problem?

Hi!

Any1 found a solution for this one? I am currently also stuck with that.

Hey guys, as I commented over at: https://www.drupal.org/node/2224803#comment-8986421, after looking at the code, I believe this is an implementation issue in services, and not a core bug. This is explicit security to protect ajax-enabled form elements, and prevent altering of the form state between ajax calls. It's unfortunate that this gets in the way of the otherwise good idea for form api validation in services. However, this is a pretty large bug.

Is there anything we can do to fix it, aside from overriding the implemented callbacks, and writing custom handlers?

It is not an implementation issue with services it is an implementation problem with how unlimited value fields behave in drupal core and the fact that is an interaction via AJAX that causes a form rebuild and hence the appending of additional (n) elements. If n is fixed then there is no issue as the form elements exist for drupal_form_submit when it generates the form.

At the end of the day services is simply a wrapper to drupal_form_submit.

You need to create custom handlers to simulate what the form build operation does. However if anyone can come up with a working generic solution we can look to add it to services but you really need to read #1066786: How to add multiple Link-field entries programmatically using drupal_form_submit? to understand the issue.

I use Services Entity API module to deal with the multi-valued field, no extra code/hook is added, it works in native,
I think the correct format of the POST data is the key of getting it done.

For example, I have a entity reference field which is multi-value (set to unlimited)
what i need to POST the data are as follows,

NOT Url encoded
any_thing_else_key=any_thing_else_value&borrow_record_multiple[0]=5284&borrow_record_multiple[1]=5283&any_thing_else_key=any_thing_else_value

With Url encoded
any_thing_else_key=any_thing_else_value&borrow_record_multiple%5B0%5D=5284&borrow_record_multiple%5B1%5D=5283&any_thing_else_key=any_thing_else_value

And the C# code are as follows

NameValueCollection nvc = new NameValueCollection();
nvc.Add("any_thing_else_key", "any_thing_else_value");
for (int i = 0; i < returnSelectedList.Length; i++)
{
    nvc.Add("borrow_record_multiple["+i+"]",  returnSelectedList[i].ID + "");
}
restReqID = getCurrentTimeStamp();
rest.EntityCreate<DrupalMyCustomEntity>(restReqID, nvc);

And the result are as follows

......
"borrow_record_multiple": [2]
0:  {
"uri": "http://192.168.1.20/vtcdemo/rest/entity_borrowrecord/5284"
"id": "5284"
"resource": "borrowrecord"
}-
1:  {
"uri": "http://192.168.1.20/vtcdemo/rest/entity_borrowrecord/5283"
"id": "5283"
"resource": "borrowrecord"
}
........

However, I am dealing with my custom entity, not node, so you may try entity_node instead of node after Services Entity API installed.

Version I am using,
Services 7.x-3.12
Services Entity API 7.x-2.0-alpha8

Cheers!