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Send one metric

Use emit for the first metric. It validates identity and field types, escapes line protocol for you, and writes to the configured local socket:

constellation-agent emit ground_station \
  --entity-id GS-001 \
  --tag site=primary \
  --field lat=34.2 \
  --field lon=-118.2 \
  --field snr=12.7 \
  --field locked=true

Expected output:

written to local socket; parsing and remote delivery are unconfirmed

That message is deliberately precise: the local write succeeded, but remote delivery is asynchronous. The next step proves the complete path.

Every metric needs:

  • one measurement, such as ground_station or link;
  • a non-empty entity_id, which becomes its topology identity;
  • at least one field.

Validate without sending​

Use --print to inspect the encoded line:

constellation-agent emit ground_station \
  --entity-id GS-001 \
  --field lat=34.2 \
  --field lon=-118.2 \
  --field snr=12.7 \
  --print

Field syntax controls type: 12.7 is a float, 42i an integer, true a Boolean, and '"001"' a string. Run constellation-agent emit --help for the full command surface.

Send canonical JSON​

printf '%s\n' '{
  "measurement": "ground_station",
  "tags": {"entity_id": "GS-001", "site": "primary"},
  "fields": {"lat": 34.2, "lon": -118.2, "snr": 12.7, "locked": true}
}' | constellation-agent emit --json

emit is for smoke tests and shell automation. A high-rate publisher should keep one direct socket connection open; that comes after verification.

Next: Verify it.