Users can add dives to their "dive log"

[sonyccd]

The idea is for divers to add dives to there datasets so they can look at them better. (This needs to be fleshed out more)

[brendanwalters]

1. Sensor: publish createDive(char format, int sensorDiveId, float latStart, longStart, latEnd, longEnd, int sampleCount, timestamp epochStart, epochEnd)

• Firebase generates new Dive document with ID firebaseDiveId (hash of properties to tolerate repeat? If not, on repeat we get two partial dives and retry)
• Firebase: poke sensor with readyToReceive(string firebaseDiveId, int sensorDiveId)

2. Sensor: loop publish diveAppend(char format, int sensorDiveId, timestamp firstDataTime, 41x6byte(depth,temp1,temp2))

• Firebase determines firebaseDiveId of "active" dive to which to append via one of three options:
  • stores both sensorDiveId and firebaseDiveId as "lastDiveId_sensor" and "lastDiveId_firebase" on the Sensor object, which it Gets
  • queries Dives that are children of this Sensor for most recent LastUpdatedAt or LastCreatedAt, uses that one (and still verifies sensorDiveId match); this avoids storing state on the Sensor
  • change message formate above: sensor sends full firebaseDiveId per packet (high overhead)

3. Sensor: with tuned backoff, publish diveDone(char format, int sensorDiveId, string firebaseDiveId)

• Firebase: count Data collection under active Dive: if == Dive.sampleCount, poke sensor with diveComplete(string firebaseDiveId, int sensorDiveId)
  -- non-response is "not done"

if Firebase ever errors, log error info under errorId, poke sensor with stopSending(string firebaseDiveId, int sensorDiveId, string errorId)

• if we receive enough of these or otherwise have to resend 3 times
• Sensor: emergency REST dump dive to raw-dive-dump endpoint for manual debugging and data recovery

for format details see:
project-hermes/hermes-sensor#24