Basic Create ANC Policy Notification Example

This sample registers and outputs messages received for Cisco Adaptive Network Control (ANC) create policy notifications via DXL and Cisco pxGrid.

Prerequisites

• The samples configuration step has been completed (see Samples Configuration).
• The DXL fabric to which the client will connect has been bridged to Cisco pxGrid.
• The Python client has been authorized to receive DXL Cisco pxGrid Notifications (see Authorize Client to Use Cisco pxGrid via DXL).
• ANC Create Policy notifications from pxGrid have been enabled (see Enable Cisco pxGrid Notifications for DXL).

Running

To run this sample execute the sample/basic/basic_anc_create_policy_notification_example.py script as follows:

python sample/basic/basic_anc_create_policy_notification_example.py

After the example starts up, the initial output should appear similar to the following:

Waiting for create policy events...

To generate a create policy notification, create an ANC policy on the Cisco Identity Services Engine (ISE) server. The policy could be created by logging into the ISE web interface and performing the following steps:

• Navigate to Operations → Adaptive Network Control → Policy List.
• On the List screen, click on the Add button.
• On the List → New screen, enter quarantine_policy in the name field, select QUARANTINE in the Action field, and press the Submit button.

A message similar to the following should appear in the output of the notification example:

{
    "action": [
        "Quarantine"
    ],
    "name": "quarantine_policy"
}

Details

The majority of the sample code is shown below:

# Create the client
with DxlClient(config) as dxl_client:

    # Connect to the fabric
    dxl_client.connect()

    logger.info("Connected to DXL fabric.")

    # Create client wrapper
    client = CiscoPxGridClient(dxl_client)

    class MyAncCreatePolicyCallback(AncCreatePolicyCallback):
        def on_create_policy(self, create_dict):
            print("on_create_policy\n" +
                  MessageUtils.dict_to_json(create_dict, pretty_print=True))

    # Attach callback for 'create policy' events
    client.anc.add_create_policy_callback(MyAncCreatePolicyCallback())

    # Wait forever
    print("Waiting for create policy events...")
    while True:
        time.sleep(60)

Once a connection is established to the DXL fabric, a dxlciscopxgridclient.client.CiscoPxGridClient instance is created which will be used to communicate with Cisco pxGrid.

Next, the dxlciscopxgridclient.client.AncClientCategory.add_create_policy_callback() method is invoked to register a callback for create policy event notifications.

When a create policy event occurs, the on_create_policy method in the MyAncCreatePolicyCallback class is invoked. The create_dict parameter passed into the callback, a dictionary (dict) which contains the content of the event notification, is displayed.