# Policy filter XR

This workflow uses UniConfig to showcase the filtering capabilities of some of our system tasks. It filters through the interfaces of the device, returns the name of the interface based on its description provided by the user and applies chosen policy on that interface.

Supported device: ios-xr -> IOSXR653_1, IOSXR653_2 & IOSXR663_1 not IOS01 & IOS02

Policy creation is not part of this workflow. The chosen policy must exist on the device before running this workflow.

# Searching the workflow

# Sync & Replace

We consider it best practice for all workflows that interact with devices to start with the tasks "Sync from network" and "Replace config with oper". This ensures that the internal databases of the FRINX Machine are in sync with the latest configuration of the device. The input of these tasks is simply the name of the node(device).

# Read device data

The next part is reading the device config. In the UNICONFIG_read_structured_device_data task, you can specify which part of the config you want to read with URI. In this case, we leave the "URI" input field empty.

# jsonJQ filter

jsonJQ is one of our system tasks that is very useful for filtering data. We use the following query expression:

.["frinx-uniconfig-topology:configuration"]["Cisco-IOS-XR-ifmgr-cfg:interface-configurations"] . "interface-configuration" | select(. != null) | .[] | select(.description == "${workflow.input.Description}") | {interface: ."interface-name"}

We search through the whole config, and under the Cisco-IOS-XR-ifmgr-cfg:interface-configurations model we find the interface with a description given by the user. The task returns the name of that interface.

# Lambda

Lambda is a generic task that can process any JS code. In this case, we use it to parse the output of the jsonJQ task. jsonJQ returns the name of the interface in a standard decoded format, e.g: "TenGigE0/0/0/0". However, we will be using that interface in URI, which means it must be encoded. We can achieve that using a simple JS script:

{return(encodeURIComponent($.lambdaValue));}

As an example, we take the interface name TenGigE0/0/0/0 and encode it to TenGigE0%2F0%2F0%2F0.

# Write & commit

Lastly, we use the output of the lambda task for the configuration. We apply a policy to the interface filtered based on its description.

# Example input

# Execution flow

# Run of the workflow

IOSXR653_1 test_map_custom