Within a multitenant environment and you want to get the tenant specific instance you are supposed to invoke
.get_tenant_instance(id) or CumulocityApp(id) (with the tenant ID). Subsequent calls to this will result in multiple bootstrap instances being created. This is not ideal.

Is there a way to get the full Cumulocity IoT managed object representation related to the ManagedObject python class representation which includes in-built/read-only fragments (e.g. lastUpdated, id, creationTime)?

I'm currently using the to_json() method, however it does not include the fragments mentioned above. Yes I could use the __dict__ method, however that would only include the python model's representation of the fields, e.g. it would have update_time rather than the Cumulocity fragmentlastUpdated.

Looking further there seems to be already some logic which looks at adding back some fragments when constructing the json dictionary, so the in-builts could potentially be added back in there. Below shows that the c8y_IsDevice is re-added into the device when marshalling to a dictionary object.

def to_json(self, only_updated=False) -> dict:
    # (no doc changes)
    object_json = super().to_json(only_updated)
    if not only_updated:
        object_json['c8y_IsDevice'] = {}
    return object_json

Note: The above example was taken from 1.5.x, so the exact implementation has changed slightly but the main point remains.

Another place where this logic could be slotted in could be the to_full_json() method, as the name might be a bit more fitting (at least from a first glance).

Background

I've been using c8yapi in another library that I've been working on to support Robot Framework tests, robotframework-c8y. Under the hood I'm using this library, and I'm mostly returning any objects as a plain dictionary to the user so they can do any followup assertions using standard python objects (and not custom classes where the user has to read through docs).

A dumbed down example would look something like this.

def assert_managed_object_existence(device_id):
    mo = client.inventory.get(device_id)
    return mo.to_json()

The idea is to get a value from Cumulocity, so some assertion, and then return the object to the user, so they could check that the managed object fragments match some expected outcome.

Method .add_child_device() should be removed from DeviceGroup, as DeviceGroup uses .add_child_asset() to associate a device with the group. Using DeviceGroup.add_child_device() for this purpose is very confusing and the results seems also incorrect as stated in below issue 1.

Issue 1.

• when use DeviceGroup.add_child_device(), the added device is not shown in the group from the tenant. However, deleting the group and its assets will also delete the device. This is very confusing.

Issue 2.

• After execute DeviceGroup.add_child_asset(), the attributes of the DeviceGroup .child_assets are still empty, which seems not right.

I would like to retrieve the device ID for a device name containing a single apostrophe (').

Running the following results in a raised exception:

>>> from c8y_api.app import SimpleCumulocityApp
>>> app = SimpleCumulocityApp()
>>> app.device_inventory.get_all(name="Sam's Device")
Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/home/sam/dev/cumulocity-python-api/c8y_api/model/inventory.py", line 194, in get_all
    def get_all(self, type: str = None, name: str = None, owner: str = None,   # noqa (type, parameters)
  File "/home/sam/dev/cumulocity-python-api/c8y_api/model/_base.py", line 522, in _iterate
    def _iterate(self, base_query, limit, parse_func):
  File "/home/sam/dev/cumulocity-python-api/c8y_api/model/_base.py", line 518, in _get_page
    def _get_page(self, base_query, page_number):
  File "/home/sam/dev/cumulocity-python-api/c8y_api/_base_api.py", line 101, in get
    def get(self, resource: str, params: dict = None, accept: str = None, ordered: bool = False) -> dict:
ValueError: Unable to perform GET request. Status: 422 Response:
{"error":"inventory/Invalid Data","message":"Find by filter query failed : Query 'name eq 'Sam's Device'' could not be understood. Please try again.","info":"https://www.cumulocity.com/guides/reference-guide/#a-name-error-reporting-a-error-reporting"}

If I apply OData conversion rules my end (i.e. use two apostrophes), the query works, like so:

>>> app.device_inventory.get_all(name="Sam''s Device")
[<c8y_api.model.manag...f1d1d0550>]

However I think this ought to be performed by c8y_api prior to sending a request.

Following alarm results in an exception:
alarm = Alarm(None, 'sag_DobotAlarm', None, deviceId, text, Alarm.Status.ACTIVE, Alarm.Severity.MAJOR)

File "C:\Users\APES\AppData\Local\Programs\Python\Python310\lib\site-packages\c8y_api\model\alarms.py", line 333, in create
super()._create(Alarm.to_full_json, *alarms)
File "C:\Users\APES\AppData\Local\Programs\Python\Python310\lib\site-packages\c8y_api\model_base.py", line 494, in _create
self.c8y.post(self.resource, json=jsonify_func(o), accept=None)
File "C:\Users\APES\AppData\Local\Programs\Python\Python310\lib\site-packages\c8y_api_base_api.py", line 190, in post
raise ValueError(f"Unable to perform POST request. Status: {r.status_code} Response:\n" + r.text)
ValueError: Unable to perform POST request. Status: 422 Response:
{"error":"undefined/validationError","message":"Following mandatory fields should be included: time","info":"https://www.cumulocity.com/guides/reference-guide/#a-name-error-reporting-a-error-reporting"}

Using now() is working fine:
alarm = Alarm(None, 'sag_DobotAlarm', datetime.now().isoformat(), deviceId, text, Alarm.Status.ACTIVE, Alarm.Severity.MAJOR)

c8y.notification2_tokens.build_websocket_uri(token) always returns wss://... instead of ws:// what is needed when running it inside of a cumulocity hosted microservice. What i do now is using my own Listener and creating the uri like this: f"{c8y.base_url.replace('http','ws')}/notification2/consumer/?token={token}"

Hi team,

Thank you for making such an awesome Python library, I really appreciate it!

Just a quick question:
I am trying to update a device’s fragment using mo.update() as below.
I can print mo.fragments and confirm the fragments have been changed, however, this change has not be updated to the database.

    def test1():
      mo = c8y.device_inventory.get(id=123)
      mo.fragments['c8y_Hardware']['serialNumber'] ='abc'
      print(mo.fragments)
      mo.update()

On the other hand, the below code works as expected.
The fragments has been changed by add_fragment function, and successfully updated to the database.

 def test2():
    mo = c8y.device_inventory.get(id=123)
    mo.add_fragment('c8y_Hardware',serialNumber='abc')
    print(mo.fragments)
    mo.update()

So it seems like [] operator can edit fragments on the managed object, but mo.update() will not update the fragments on the device?

Is it possible if you could tell me what I’ve done something wrong on test1()?

Or is it because the API can not tell the difference on the fragments when [] operator is used?

My c8y-api version is 1.9.1.

Much appreciated!

Regards
Henry

Function DeviceInventory.get_all() delegates its call to its parent, Inventory.get_all(), which in turn calls self.select(). That results in a parameter missmatch as self refers to an instance of DeviceInventory while the function parameters match with Inventory.select()

Replacing line 784 in module/inventory.py with
return [ x for x in self.select( type = type, name = name, page_size = page_size ) ]
resolved the issue for me

Then SimpleCumulocityApp without using "get_user_instance" and just use the SimpleCumulocityApp directly will get a 401 then runing as a microservice on C8Y, if running as a local docker container the same call works.
The python api is only using the C8Y_USER and C8Y_PASSWORD and that works localy but then deployed the C8Y_TENANT is also needed for the username the call should be: auth=HTTPBasicAuth(f'{C8Y_TENANT}/{C8Y_USER}', f'{C8Y_PASSWORD}') in the SimpleCumulocityApp init function altrnatively not set the Auth value at all, since it is set correctly in the CumulocityRestApi init function.

I would like to send a query to the inventory api:

filter_01 = f"$filter=applicationId eq '{app_id}' and name eq '{APPLICATION_NAME}'"
managed_objects_app = c8y.inventory.select(query=filter_01)

When I debug the url I don't see that it is considered:
DEBUG:urllib3.connectionpool:https://SOME_TENANT.cumulocity.com:443 "GET /inventory/managedObjects?pageSize=1000&currentPage=1 HTTP/1.1" 200 None