kevinveenbirkenbachandClaude Opus 5.5
ae259a9f58
The local 061 Nextcloud swarm step failed on every lab node in
"Ask the driver which CUDA devices this host carries" with
"[Errno 2] No such file or directory: b'nvidia-smi'". The lab nodes are
privileged containers (compose/swarm/compose.yml), so on a workstation
with an NVIDIA card they see the host's /dev/nvidia0, but they carry no
driver. The device node alone made them GPU hosts, for the GPU include
and for lookup('gpu') alike, which would also have picked a -cuda image
and runtime: nvidia for a GPU service there.
The role now stats SYS_SVC_CONTAINER_GPU_DRIVER (/usr/bin/nvidia-smi)
first and stats the device node only where the driver exists; the
skipped register reads as "no device" in lookup('gpu'), and the include
requires a device stat that ran and found the node. The query runs the
same binary the detection probed. Hosts with driver and device (bare
metal with the driver, the compose dev container through the GPU
override) and hosts without a device (CI) behave as before.
test_gpu_detection walks the real tasks over the four driver/device
cells and fails on the old 00_core.yml in exactly the device-without-
driver cell.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Ansible Plugins (plugins/) 🧩
This document is the central reference for plugin types and plugin placement in Infinito.Nexus.
Not to be confused with application addons. This
plugins/directory holds Ansible plugins (action / filter / lookup) that extend the automation engine itself. Some applications also call their own extensions "plugins" (e.g. Nextcloud, WordPress). Those application-level extensions, whatever the app calls them natively, are declared through the unifiedmeta/addons/contract, documented in Unified Addons. An app "plugin" is an addon; an Ansible plugin lives here.
Current Project Layout 🗂️
plugins/
├── action/ # custom action plugins
├── filter/ # custom Jinja2 filters
└── lookup/ # custom lookup plugins
Configured plugin paths in this repository are defined in ansible.cfg:
action_plugins = ./plugins/actionfilter_plugins = ./plugins/filterlookup_plugins = ./plugins/lookup
All Common Ansible Plugin Types 📚
The table below summarizes common Ansible plugin types and their conventional directory names.
| Emoji | Plugin Type | Conventional Directory | Purpose |
|---|---|---|---|
| ⚙️ | action |
action_plugins/ or plugins/action/ |
Wrap/extend module execution behavior at task runtime. |
| 🔐 | become |
become_plugins/ |
Implement privilege escalation methods. |
| 💾 | cache |
cache_plugins/ |
Persist gathered facts and cached data between runs. |
| 📣 | callback |
callback_plugins/ |
React to play/task events (logging, reporting, notifications). |
| 🖧 | cliconf |
cliconf_plugins/ |
Define CLI command transport behavior (mainly network platforms). |
| 🔌 | connection |
connection_plugins/ |
Control how Ansible connects to targets (ssh, local, etc.). |
| 🔍 | filter |
filter_plugins/ or plugins/filter/ |
Add Jinja2 filters for data transformation. |
| 🌐 | httpapi |
httpapi_plugins/ |
API transport layer over HTTP(S), mainly for network devices. |
| 🧭 | inventory |
inventory_plugins/ |
Build dynamic inventories from APIs, services, or files. |
| 👉 | lookup |
lookup_plugins/ or plugins/lookup/ |
Resolve dynamic values during playbook processing. |
| 🛰️ | netconf |
netconf_plugins/ |
NETCONF transport integration for network automation. |
| 🐚 | shell |
shell_plugins/ |
Adjust shell command wrapping/execution behavior. |
| 🧠 | strategy |
strategy_plugins/ |
Customize task scheduling/execution strategy. |
| ✅ | test |
test_plugins/ |
Add Jinja2 tests used in conditions and templates. |
| 📦 | vars |
vars_plugins/ |
Load variables from custom sources. |
Which Plugin Type to Use 🧭
action ⚙️
Use when task execution behavior itself must be changed or wrapped.
Examples:
- centralized retry logic (
uri_retry.py), - argument normalization before module dispatch,
- pre/post task orchestration.
filter 🔍
Use for pure data transformation in Jinja2 expressions.
Examples:
- mapping/normalizing dictionaries,
- deriving computed fields for templates,
- deterministic formatting helpers.
lookup 👉
Use when a value must be dynamically resolved at runtime.
Examples:
- computing IDs from role metadata,
- resolving paths/version data,
- reading structured project data for templates/tasks.
callback 📣
Use to hook into execution events and shape output/reporting.
inventory 🧭
Use when host/group data should come from a dynamic source.
strategy 🧠
Use to alter how tasks are scheduled/executed across hosts.
vars 📦
Use to load variables from custom backends.
connection, become, shell 🔌🔐🐚
Use to customize low-level execution and privilege mechanics.
cache 💾
Use to persist facts/results across runs for performance and consistency.
cliconf, httpapi, netconf 🖧🌐🛰️
Use in network automation contexts requiring protocol-specific transport behavior.
test ✅
Use to add custom Jinja2 test operators for conditional logic.
Best Practices 🧪
- Keep plugin interfaces explicit and stable.
- Keep plugin logic focused; move shared logic to
utils/. - Add unit tests for plugin behavior and integration tests for end-to-end flows.
- Prefer deterministic outputs and avoid hidden global state.
- Document any plugin-specific task arguments in the plugin docstring and README.
References 🔗
- Ansible plugin development: docs.ansible.com
- Ansible plugin index (all types): docs.ansible.com
- Ansible
ansible-docplugin types:ansible-doc -t ...