Think about logic for filtering HFP data in MQTT broker

[mjaakko]

Currently there is some HFP data that we want to filter from the public MQTT feed. Think about what logic we should use for detecting this data and what to do with the filtered data (publish to another topic?)

[mjaakko]

Use cases:

1. Filtering tram practice runs

• This can be detected if the vehicle is significantly delayed (i.e. value of dl field is over certain limit)
• If dl is unreliable or unavailable in some cases, other option would be comparing values of oday + start to tst (e.g. check if the trip would have started more than 2 hours in the past compared to the current time)
  • This method might be unreliable, because the time limit has to be long enough so that long trips don't get filtered
  • This method also allows filtering other invalid data (not just practice runs)

2. Filtering data with oday in the past

• At least in metro HFP, there are some bugs where vehicles get "stuck" on their trip and keep sending data when in depot etc.
• oday should be the current or the previous day, otherwise there is some problem in the data