Replace old used-to-be-GORM datastructures (#104305) with sqlc-generated
structs. This also makes it possible to use more specific structs that
are more taylored to the specific queries, increasing efficiency.
This commit mostly deals with workers, including the sleep schedule and
task scheduler.
Functional changes are kept to a minimum, as the API still serves the
same data.
Because this work covers so much of Flamenco's code, it's been split up
into different commits. Each commit brings Flamenco to a state where it
compiles and unit tests pass. Only the result of the final commit has
actually been tested properly.
Ref: #104343
Set the default MQTT topic prefix to 'flamenco'. It can still be overridden
by the config in the YAML file, but it's nice to have a sensible default
when people don't configure this.
This introduces the concept of 'event listener', which is now used by
the farm status service to respond to events on the event bus.
This makes it possible to reduce the regular poll period from 5 to 30
seconds. That's now only necessary as backup, just in case events are
missed or otherwise things change without the event bus logic noticing.
SocketIO has 'rooms' and 'event types'. The 'event type' is set via
reflection of the OpenAPI type of the event payload. This has to be set
up in a mapping, though, and if that mapping is incomplete, an error will
now be logged.
Send an event to the event bus whenever the farm status changes. The event
contains a farm status report (like `{status: "active"}`), and is sent to
the `/status` topic.
Note that at this moment the status is only polled every X seconds, and
thus may lag behind other events.
Send events on Manager startup & shutdown. To make this possible, events
sent to MQTT are now queued up until an MQTT server can be reached.
Otherwise the startup event would be sent before the MQTT connection was
established.
Fix SocketIO subscriptions so that the client also subscribes to
job-specific last-rendered images whenever subscribing to job-specific
events. These are sent to another event topic, and thus need some extra
care. Before the introduction of the generic event bus, both message types
were sent to the same topic, but that's not supported by MQTT, and so things
had to change.
Introduce an "event bus"-like system. It's more like a fan-out
broadcaster for certain events. Instead of directly sending events to
SocketIO, they are now sent to the broker, which in turn sends it to any
registered "forwarder". Currently there is ony one forwarder, for
SocketIO.
This opens the door for a proper MQTT client that sends the same events
to an MQTT server.
