Update relationship via REST API

Hello, We recommend against modifying the related_id of a relationship directly. Instead, you should delete the existing relationship and then create a new relationship to the desired item. You can take a look at this blog post for an example of how to both delete and create an item through the REST API. Chris

---

Christopher Gillis Aras Labs Software Engineer

Hello, We recommend against modifying the related_id of a relationship directly. Instead, you should delete the existing relationship and then create a new relationship to the desired item. You can take a look at this blog post for an example of how to both delete and create an item through the REST API. Chris

---

Christopher Gillis Aras Labs Software Engineer

Hi Chris, is there a reason why it´s not recommended to change the related_id directly? I have a "replace this Part in the BOM with the latest generation of this Part" Action that can be used on BOM items. The Action will replace the related_id. I agree that for certain ItemTypes replacing the related_id may cause some problems, as changing the Relationshp often triggers additional Methods. I think ItemType File is one potential candidate that would cause us trouble. But is there something else that could go wrong, espcially considering the ItemType "Part BOM"? Angela

Hi Chris, If I try to delete the relationship to an existing file first, I still get the ItemIsNotLockedException. I am trying to send the delete request as shown in the documentation:

To remove a relationship, the client sends a DELETE request to the $ref URL of the corresponding relationship property, passing the $id query string option: DELETE host/.../$ref

Here is my request:

DELETE host/.../Document File/$ref?$id=Document File('30776875F5674ECA8AE3ED803CA8B4B4')

Here is the response:

{
    "error": {
        "code": "SOAP-ENV:Server.ItemIsNotLockedException",
        "message": "Aras.Server.Core.ItemIsNotLockedException"
    }
}

Adding the lock action does not help. Mark

Okay. So it appears  you need to do an explicit lock call first: POST host/.../Document('178D8999B5B54EBB8F943E9934088A03') { "@aras.action": "lock" } After that, I can delete the relationship. Finally, I have to send an explicit unlock. It would be nice if there was a way to do all of this in a single call. Mark

Another issue is after you delete the relationship, the previous Document ID is no longer valid. So an additional query is needed to get the ID of the modified Document.

Hi Mark, If you know the ID of the Document File relationship, you could perform a single REST call like localhost/.../Document File('5B2466563B5547FAA8268EC4E5F4C5F8'). This will delete the relationship directly without updating the parent at all, so the ID will be the same. Please note that if you have version tracking enabled on your Document ItemType, this kind of REST call will not create a new version of the parent Document. Chris

---

Christopher Gillis Aras Labs Software Engineer

Hi Chris, That worked perfect for the delete. To create the relationship, I am first locking the Document, creating the Document File relationship, querying the Document for its new ID, and then unlocking the Document:

def attach_file(s, keyed_name, fileId, item_id, item_type='Document', rel_type='Document File'):
    # lock
    data = { '@aras.action': 'lock' }
    r = s.post(
       host + "/InnovatorServer/Server/odata/{0}('{1}')".format(item_type, item_id),
       headers = REST_HEADERS,
       data=json.dumps(data))
    r.raise_for_status()
    # Create relationship
    data = { '[email protected]': "File('{0}')".format(fileId) }
    r = s.post(
        host + "/InnovatorServer/Server/odata/{0}('{1}')/{2}".format(item_type, item_id, rel_type),
        headers = REST_HEADERS,
        data=json.dumps(data))
    r.raise_for_status()
    # Get the updated item
    r = s.get(
        host + "/InnovatorServer/Server/odata/{0}?$filter=keyed_name eq '{1}'".format(item_type, keyed_name),
        headers = REST_HEADERS)
    r.raise_for_status()
    item_id = r.json()['value'][0]['id']
    # Unlock
    data = { '@aras.action': 'unlock' }
    r = s.post(
        host + "/InnovatorServer/Server/odata/{0}('{1}')".format(item_type, item_id),
        headers = REST_HEADERS,
        data=json.dumps(data))
    r.raise_for_status()

Is there a cleaner way to do this? Thanks, Mark