The cosmos generator linked a consumer to its provider only through an '<role>' in group_names reference or an explicit provides: name. A hard dependency has neither -- pinning the provider on unconditionally is exactly what removes the Jinja reference the generator was reading -- so web-svc-asset's bond to web-svc-file vanished from the diagram the moment it became binding. Match a service key against the provider's own primary key from the registry, in both directions. Services the role turns off drew a solid 1:1 edge, claiming a mandatory relationship for something that carries nothing at deploy time. They now render as a red 0..0 edge; edge merging gained a real precedence so a provider consumed through two keys stays live when only one is off. Named colour, not hex: a '#' opens an entity code in the mermaid lexer and turns the whole diagram into a parse error on GitHub. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Systemd Timer
Description
This role configures a systemd timer to periodically start a corresponding service. It uses a Jinja2 template to create a timer unit file that specifies the scheduling parameters (such as OnCalendar and RandomizedDelaySec) and then restarts the timer service accordingly.
Overview
Optimized for automated task scheduling in a systemd environment, this role:
- Generates a timer unit file for a given service (using the
system_service_timer_servicevariable). - Reloads and restarts the timer using systemd to ensure that changes take effect.
- Supports dynamic configuration of scheduling parameters via variables like
system_service_on_calendarandRANDOMIZED_DELAY_SEC.
Cosmos
The diagram places Systemd Timer in the Infinito.Nexus cosmos: the components it deploys (capabilities), the central services it consumes (dependencies), and its outward reach (federation and bridged external networks).
flowchart LR
subgraph role [sys-timer 💻]
svc_timer["timer"]
end
Solid 1:1 edges are fixed relationships; dashed 0..1 edges are conditional (enabled only in matching deployments); red 0..0 edges are turned off in this role. Node markers show the role's deploy modes (💻 host, 🐳 compose, 🐝 swarm); ❌ marks a service that is explicitly turned off, and ⚙️ an Ansible role dependency declared in meta/main.yml.
Purpose
The primary purpose of this role is to provide a reusable mechanism for scheduling recurring tasks on a system. By creating and managing a systemd timer unit, the role ensures that specified services are automatically started at defined intervals, enhancing system automation and reliability.
Features
- Dynamic Timer Configuration: Uses a Jinja2 template to create a timer unit file based on provided variables.
- Automated Service Management: Automatically reloads the systemd daemon and restarts the timer when changes are detected.
- Flexible Scheduling: Supports configuration of parameters such as OnCalendar and RandomizedDelaySec for precise control over task timing.
- Persistent Timers: Optionally enables persistent timer behavior to ensure missed activations are handled.
Credits
Implemented by Kevin Veen-Birkenbach. Part of the Infinito.Nexus Project and maintained by Kevin Veen-Birkenbach. Licensed under the Infinito.Nexus Community License (Non-Commercial).