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Merging upstream version 1.3.0.

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Signed-off-by: Daniel Baumann <daniel@debian.org>
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Daniel Baumann 2025-03-17 07:33:51 +01:00
parent 5b922100c9
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Signed by: daniel
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67
docs/advanced_usages/caching.md
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@ -1,5 +1,5 @@
<!--
~ Copyright (c) 2023-2024 Arista Networks, Inc.
~ Copyright (c) 2023-2025 Arista Networks, Inc.
~ Use of this source code is governed by the Apache License 2.0
~ that can be found in the LICENSE file.
-->
@ -8,30 +8,17 @@ ANTA is a streamlined Python framework designed for efficient interaction with n
## Configuration
By default, ANTA utilizes [aiocache](https://github.com/aio-libs/aiocache)'s memory cache backend, also called [`SimpleMemoryCache`](https://aiocache.aio-libs.org/en/v0.12.2/caches.html#simplememorycache). This library aims for simplicity and supports asynchronous operations to go along with Python `asyncio` used in ANTA.
The `_init_cache()` method of the [AntaDevice](../api/device.md#anta.device.AntaDevice) abstract class initializes the cache. Child classes can override this method to tweak the cache configuration:
```python
def _init_cache(self) -> None:
"""
Initialize cache for the device, can be overridden by subclasses to manipulate how it works
"""
self.cache = Cache(cache_class=Cache.MEMORY, ttl=60, namespace=self.name, plugins=[HitMissRatioPlugin()])
self.cache_locks = defaultdict(asyncio.Lock)
```
The cache is also configured with `aiocache`'s [`HitMissRatioPlugin`](https://aiocache.aio-libs.org/en/v0.12.2/plugins.html#hitmissratioplugin) plugin to calculate the ratio of hits the cache has and give useful statistics for logging purposes in ANTA.
## Cache key design
The cache is initialized per `AntaDevice` and uses the following cache key design:
`<device_name>:<uid>`
The `uid` is an attribute of [AntaCommand](../api/models.md#anta.models.AntaCommand), which is a unique identifier generated from the command, version, revision and output format.
The `uid` is an attribute of [AntaCommand](../api/commands.md#anta.models.AntaCommand), which is a unique identifier generated from the command, version, revision and output format.
Each UID has its own asyncio lock. This design allows coroutines that need to access the cache for different UIDs to do so concurrently. The locks are managed by the `self.cache_locks` dictionary.
Each UID has its own asyncio lock. This design allows coroutines that need to access the cache for different UIDs to do so concurrently. The locks are managed by the `AntaCache.locks` dictionary.
## Mechanisms
@ -45,37 +32,37 @@ There might be scenarios where caching is not wanted. You can disable caching in
1. Caching can be disabled globally, for **ALL** commands on **ALL** devices, using the `--disable-cache` global flag when invoking anta at the [CLI](../cli/overview.md#invoking-anta-cli):
```bash
anta --disable-cache --username arista --password arista nrfu table
```
```bash
anta --disable-cache --username arista --password arista nrfu table
```
2. Caching can be disabled per device, network or range by setting the `disable_cache` key to `True` when defining the ANTA [Inventory](../usage-inventory-catalog.md#device-inventory) file:
```yaml
anta_inventory:
hosts:
- host: 172.20.20.101
name: DC1-SPINE1
tags: ["SPINE", "DC1"]
disable_cache: True # Set this key to True
- host: 172.20.20.102
name: DC1-SPINE2
tags: ["SPINE", "DC1"]
disable_cache: False # Optional since it's the default
```yaml
anta_inventory:
hosts:
- host: 172.20.20.101
name: DC1-SPINE1
tags: ["SPINE", "DC1"]
disable_cache: True # Set this key to True
- host: 172.20.20.102
name: DC1-SPINE2
tags: ["SPINE", "DC1"]
disable_cache: False # Optional since it's the default
networks:
- network: "172.21.21.0/24"
disable_cache: True
networks:
- network: "172.21.21.0/24"
disable_cache: True
ranges:
- start: 172.22.22.10
end: 172.22.22.19
disable_cache: True
```
ranges:
- start: 172.22.22.10
end: 172.22.22.19
disable_cache: True
```
This approach effectively disables caching for **ALL** commands sent to devices targeted by the `disable_cache` key.
This approach effectively disables caching for **ALL** commands sent to devices targeted by the `disable_cache` key.
3. For tests developers, caching can be disabled for a specific [`AntaCommand`](../api/models.md#anta.models.AntaCommand) or [`AntaTemplate`](../api/models.md#anta.models.AntaTemplate) by setting the `use_cache` attribute to `False`. That means the command output will always be collected on the device and therefore, never use caching.
3. For tests developers, caching can be disabled for a specific [`AntaCommand`](../api/commands.md#anta.models.AntaCommand) or [`AntaTemplate`](../api/commands.md#anta.models.AntaTemplate) by setting the `use_cache` attribute to `False`. That means the command output will always be collected on the device and therefore, never use caching.
### Disable caching in a child class of `AntaDevice`