Stream

Stream messages publish lifecycle/state information for configured streams. They do not carry status data values.

<node>/stream/<code>/<stream>

Examples:

45fe/stream/tlc.groups/live      # state for live stream of signal groups
45fe/stream/tlc.groups/hourly    # state for hourly stream of signal groups

Payload (CBOR encoded JSON) is explicitly defined as:

{"state": "running" | "stopped"}

Rules:

• The payload MUST include exactly one key: state.
• state MUST be one of: running, stopped.
• No additional payload keys are currently defined for this topic.

MQTT Behavior

• QoS: 1
• Retain: true

Each stream topic keeps the latest known state as a retained message, so supervisors can recover stream state immediately after subscribing.

Runtime control is performed via Throttle messages.

When to Publish

A node publishes stream state:

• when a stream starts
• when a stream stops
• when stream configuration changes affect effective runtime state
• when the node connects (republish current state for all streams)