AVD Plugins & Filters
Arista AVD Plugins¶
Table of Contents:
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.
An optional sort_key
can be specified, to sort on content of certain key if the items are dictionaries.
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 %}
{% for item in list_of_dicts_to_natural_sort | arista.avd.natural_sort('name') %}
{{ dict_sorted_on_name }}
{% 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 ... ) }}
convert_dicts filter¶
The arista.avd.convert_dicts
filter will convert a dictionary containing nested dictionaries to a list of dictionaries
and insert the outer dictionary keys into each list item using the primary_key name
(key name is configurable).
This filter is intended for:
- Seemless data model migration from dictionaries to lists.
- Improve Ansible’s processing performance when dealing with large dictionaries by converting them to lists of dictionaries.
Note: If the variable is already a list, it will pass through untouched
To use this filter:
{# convert list of dictionary with default `name:` as the primary key #}
{% set example_list = example_dictionary | arista.avd.convert_dicts %}
{% for example_item in example_list %}
item primary key is {{ example_item.name }}
{% endfor %}
{# convert list of dictionary with `id:` set as the primary key #}
{% set example_list = example_dictionary | arista.avd.convert_dicts('id') %}
{% for example_item in example_list %}
item primary key is {{ example_item.id }}
{% endfor %}
ethernet segment identifiers management filter¶
To help provide consistency when configuring EVPN A/A ESI values, the esi_management
filter plugin provides an abstraction in the form of a short_esi
key. short_esi
is an abbreviated 3 octets value to encode Ethernet Segment ID, LACP ID and route target. Transformation from abstraction to network values is managed the following jinja2 filters:
generate_esi filter¶
The arista.avd.generate_esi
filter transforms short_esi: 0303:0202:0101
with prefix 0000:0000
to EVPN ESI: 0000:0000:0303:0202:0101
example:
esi: {{ l2leaf.node_groups[l2leaf_node_group].short_esi | arista.avd.generate_esi }}
generate_lacp_id filter¶
The arista.avd.generate_lacp_id
filter transforms short_esi: 0303:0202:0101
to LACP ID format format: 0303.0202.0101
example:
lacp_id: {{ l2leaf.node_groups[l2leaf_node_group].short_esi | arista.avd.generate_lacp_id }}
generate_route_target filter¶
The arista.avd.generate_route_target
filter transforms short_esi: 0303:0202:0101
to route-target format: 03:03:02:02:01:01
example:
rt: {{ l2leaf.node_groups[l2leaf_node_group].short_esi | arista.avd.generate_route_target }}
add_md_toc filter¶
The arista.avd.add_md_toc
filter will parse the input MarkDown and add a TOC between the toc_markers
.
The module is used in eos_designs
to create Table Of Contents for Fabric Documentation.
The module is used in eos_cli_config_gen
to create Table Of Contents for Device Documentation.
To use this filter:
{{ markdown string | arista.avd.add_md_toc(skip_lines=0, toc_levels=2, toc_marker='<!-- toc -->') }}
Argument | description | type | optional | default value |
---|---|---|---|---|
skip_lines | Skip first x lines when parsing MD file | Integer | True | 0 |
toc_levels | How many levels of headings will be included in the TOC | Integer | True | 2 |
toc_marker | TOC will be inserted or updated between two of these markers in the MD file | String | True | "<!-- toc -->" |
example:
To use this module:
tasks:
- name: Generate fabric documentation
tags: [build, provision, documentation]
run_once: true
delegate_to: localhost
check_mode: no
copy:
content: "{{ lookup('template','documentation/fabric-documentation.j2') | arista.avd.add_md_toc(skip_lines=3) }}"
dest: "{{ fabric_dir }}/{{ fabric_name }}-documentation.md"
mode: 0664
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 test_value
argument to test if the value equals this.
The optional var_type
argument can be used to also test if the variable is of the expected type.
Optionally the test can emit warnings or errors if the test fails.
Compared to the builtin is defined
test, this test will also test for None
and can even test for a specific value and/or class.
Syntax:
{% <value> is arista.avd.defined(test_value=<test_value>,
var_type=['float', 'int', 'str', 'list', 'dict', 'tuple', 'bool'],
fail_action=['warning','error'],
var_name=<string representing name of 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
Warnings or Errors can be emitted with the optional arguments fail_action
and var_name
:
{% if my_dict.my_list[12].my_var is arista.avd.defined(fail_action='warning', var_name='my_dict.my_list[12].my_var') %}
>>> [WARNING]: my_dict.my_list[12].my_var was expected but not set. Output may be incorrect or incomplete!
{% if my_dict.my_list[12].my_var is arista.avd.defined(fail_action='error', var_name='my_dict.my_list[12].my_var') %}
>>> fatal: [DC2-RS1]: FAILED! => {"msg": "my_dict.my_list[12].my_var was expected but not set!"}
{% set my_dict.my_list[12].my_var = 'not_my_value' %}
{% if my_dict.my_list[12].my_var is arista.avd.defined('my_value', fail_action='warning', var_name='my_dict.my_list[12].my_var') %}
>>> [WARNING]: my_dict.my_list[12].my_var was set to not_my_value but we expected my_value. Output may be incorrect or incomplete!
{% if my_dict.my_list[12].my_var is arista.avd.defined('my_value', fail_action='error', var_name='my_dict.my_list[12].my_var') %}
>>> fatal: [DC2-RS1]: FAILED! => {"msg": "my_dict.my_list[12].my_var was set to not_my_value but we expected my_value!"}
contains test¶
The arista.avd.contains
test will test if a list contains one or more of the supplied value(s).
The test will return False
if either the passed value or the test_values are Undefined
or none
.
The test accepts either a single test_value or a list of test_values. To use this test:
{% if my_list is arista.avd.contains(item) %}Match{% endif %}
{# or #}
{% if my_list is arista.avd.contains(item_list) %}Match{% endif %}
example
The arista.avd.contains
is used in the role eos_designs
in combination with selectattr
to parse the platform_settings
list
for an element where switch_platform
is contained in the platforms
attribute.
Data model:
platform_settings:
- platforms: [default]
reload_delay:
mlag: 300
non_mlag: 330
- platforms: [ 7280R, 7280R2, 7500R, 7500R2 ]
tcam_profile: vxlan-routing
lag_hardware_only: true
reload_delay:
mlag: 900
non_mlag: 1020
- platforms: [ 7280R3, 7500R3, 7800R3 ]
reload_delay:
mlag: 900
non_mlag: 1020
Jinja template without the selectattr
and arista.avd.contains
test:
switch:
{% set ns = namespace() %}
{% for platform_setting in platform_settings %}
{% set ns.platform_defined = false %}
{% if switch_platform in platform_setting.platforms %}
{% set ns.platform_defined = true ]}
platform_settings: {{ platform_setting }}
{% break; %}
{% endif %}
{% endfor %}
{% for platform_setting in platform_settings if ns.platform_defined == false %}
{% if 'default' in platform_setting.platforms %}
platform_settings: {{ platform_setting }}
{% break; %}
{% endif %}
{% endfor %}
Jinja template with the selectattr
and arista.avd.contains
test:
switch:
platform_settings: {{ platform_settings | selectattr("platforms", "arista.avd.contains", switch_platform) | first | arista.avd.default(
platform_settings | selectattr("platforms", "arista.avd.contains", "default") | first) }}
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 a structure of data to configure 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
Build Configuration to publish configlets to CloudVision¶
The arista.avd.configlet_build_config
module provides the following capabilities:
- Build arista.cvp.configlet configuration.
- Build configuration to publish configlets to Cloudvision.
options:
- configlet_build_config:
configlet_dir: "< Directory where configlets are located | Required >"
configlet_prefix: "< Prefix to append on configlet | Required >"
destination: "< File where to save information | Optional >"
configlet_extension: "< File extension to look for | Default 'conf' >"
example:
# tasks file for configlet_build_config
- name: generate intended variables
tags: [build, provision]
configlet_build_config:
configlet_dir: "/path/to/configlets/folder/"
configlet_prefix: "AVD_"
configlet_extension: "cfg"
YAML Templates to Facts¶
The arista.avd.yaml_templates_to_facts
module is an Ansible Action Plugin providing the following capabilities:
- Set Facts based on one or more Jinja2 templates producing YAML output.
- Recursively combining output of templates to allow templates to update overlapping parts of the data models.
- Facts set by one template will be accessible by the next templates
- Returned Facts can be set below a specific
root_key
- Facts returned templates can be stripped for
null
values to avoid them overwriting previous set facts
The module is used in eos_designs
first to set facts for devices and then to set the structured_configuration
variable based on all the eos_designs
templates.
The module arguments are:
- yaml_templates_to_facts:
root_key: < optional root_key name >
templates:
# Path to template file
- template: "< template file >"
options:
# Merge strategy for lists for Ansible Combine filter. See Ansible Combine filter for details.
list_merge: < append (default) | replace | keep | prepend | append_rp | prepend_rp >
# Filter out keys from the generated output if value is null/none/undefined
strip_empty_keys: < true (default) | false >
# Output list 'avd_yaml_templates_to_facts_debug' with timestamps of each performed action.
debug: < true | false (default) >
# Destination path. If set, the output facts will also be written to this path.
# Autodetects data format based on file suffix. '.yml', '.yaml' -> YAML, default -> JSON
dest: < path >
# If true the output data will be run through another jinja2 rendering before returning.
# This is to resolve any input values with inline jinja using variables/facts set by the input templates.
template_output: < true | false (default) >
example:
- name: Set AVD facts
tags: [build, provision]
yaml_templates_to_facts:
templates: "{{ templates.facts }}"
delegate_to: localhost
check_mode: no
changed_when: False
- name: Generate device configuration in structured format
tags: [build, provision]
yaml_templates_to_facts:
templates: "{{ templates.structured_config }}"
dest: "{{ structured_dir }}/{{ inventory_hostname }}.{{ avd_structured_config_file_format }}"
template_output: True
delegate_to: localhost
check_mode: no
register: structured_config
Role default variables applied to this example:
# Design variables
design:
type: "l3ls-evpn"
templates:
# Templates defined per design
l3ls-evpn:
facts:
# Set general "switch.*" variables
- template: "facts/main.j2"
# Set design specific "switch.*" variables
- template: "facts/main.j2"
structured_config:
# Render Structured Configuration
# Base features
- template: "base/main.j2"
# MLAG feature
- template: "mlag/main.j2"
# Underlay feature
- template: "underlay/main.j2"
# Overlay feature
- template: "overlay/main.j2"
# L3 Edge feature
- template: "l3_edge/main.j2"
# Tenants feature
- template: "network_services/main.j2"
# Connected Endpoints feature
- template: "connected_endpoints/main.j2"
# Merge custom_structured_configuration last
- template: "custom-structured-configuration-from-var.j2"
options:
list_merge: "{{ custom_structured_configuration_list_merge }}"
strip_empty_keys: false