AVD Plugins & Filters

Arista AVD Plugins¶

Table of Contents:

Arista AVD Plugins

Plugin Filters¶

Arista AVD provides built-in filters to help extend jinja2 templates with functionality and improve code readability.

list_compress filter¶

The arista.avd.list_compress filter provides the capabilities to compress a list of integers and return as a string for example:

  - [1,2,3,4,5] -> "1-5"
  - [1,2,3,7,8] -> "1-3,7-8"

To use this filter:

{{ list_to_compress | arista.avd.list_compress }}

natural_sort filter¶

The arista.avd.natural_sort filter provides the capabilities to sort a list or a dictionary of integers and/or strings that contain alphanumeric characters naturally. When leveraged on a dictionary, only the key value will be returned.

The filter will return an empty list if the value parsed to arista.avd.natural_sort is none or undefined.

To use this filter:

{% for item in dictionary_to_natural_sort | arista.avd.natural_sort %}
{{ natural_sorted_item }}
{% endfor %}

default filter¶

The arista.avd.default filter can provide the same basic capability as the builtin default filter. It will return the input value only if it is valid and if not, provide a default value instead. Our custom filter requires a value to be not undefined and not None to pass through. Furthermore the filter allows multiple default values as arguments, which will undergo the same validation one after one until we find a valid default value. As a last resort the filter will return None.

To use this filter:

{{ variable | arista.avd.default( default_value_1 , default_value_2 ... ) }}

Plugin Tests¶

Arista AVD provides built-in test plugins to help verify data efficiently in jinja2 templates

defined test¶

The arista.avd.defined test will return False if the passed value is Undefined or none. Else it will return True. arista.avd.defined test also accepts an optional argument to test if the value equals this argument.

Compared to the builtin is defined test, this test will also test for none and can even test for a specific value.

To use this test:

{% if extremely_long_variable_name is arista.avd.defined %}
text : {{ extremely_long_variable_name }}
{% endif %}
{% if extremely_long_variable_name is arista.avd.defined("something") %}
text : {{ extremely_long_variable_name }}
{% endif %}
Feature is {{ "not " if extremely_long_variable_name is not arista.avd.defined }}configured

The arista.avd.defined test can be useful as an alternative to:

{% if extremely_long_variable_name is defined and extremely_long_variable_name is not none %}
text : {{ extremely_long_variable_name }}
{% endif %}
{% if extremely_long_variable_name is defined and extremely_long_variable_name == "something" %}
text : {{ extremely_long_variable_name }}
{% endif %}
Feature is {{ "not " if extremely_long_variable_name is defined and extremely_long_variable_name is not none }}configured

Modules¶

Inventory to CloudVision Containers¶

The arista.avd.inventory_to_container module provides following capabilities: - Transform inventory groups into CloudVision containers topology. - Create list of configlets definition.

It saves everything in a YAML file using destination keyword.

It is a module to build structure of data to configure on a CloudVision server. Output is ready to be passed to arista.cvp to configure CloudVision.

Example:

To use this module:

tasks:
  - name: generate intended variables
    tags: [always]
    inventory_to_container:
      inventory: '{{ inventory_file }}'
      container_root: '{{ container_root }}'
      configlet_dir: 'intended/configs'
      configlet_prefix: '{{ configlets_prefix }}'
      destination: '{{playbook_dir}}/intended/structured_configs/{{inventory_hostname}}.yml'

Inventory example applied to this example:

all:
  children:
# DC1_Fabric - EVPN Fabric running in home lab
    DC1:
      children:
        DC1_FABRIC:
          children:
            DC1_SPINES:
              hosts:
                DC1-SPINE1:
                DC1-SPINE2:
            DC1_L3LEAFS:
              children:
                DC1_LEAF1:
                  hosts:
                    DC1-LEAF1A:
                    DC1-LEAF1B:
                DC1_LEAF2:
                  hosts:
                    DC1-LEAF2A:
                    DC1-LEAF2B:

Generated output ready to be used by arista.cvp collection:

---
CVP_DEVICES:
  DC1-SPINE1:
    name: DC1-SPINE1
    parentContainerName: DC1_SPINES
    configlets:
        - DC1-AVD_DC1-SPINE1
    imageBundle: []

CVP_CONTAINERS:
  DC1_LEAF1:
    parent_container: DC1_L3LEAFS
  DC1_FABRIC:
    parent_container: Tenant
  DC1_L3LEAFS:
    parent_container: DC1_FABRIC
  DC1_LEAF2:
    parent_container: DC1_L3LEAFS
  DC1_SPINES:
    parent_container: DC1_FABRIC