Write to more than one influx database

[chris0348]

As suggested by paddyb on Slack on the 3rd of December, it would be a great benefit if the influx-plugin could be configured to write to more than one influx database.

Exemplary use cases:

• Write to a local influx database as well as to a cloud-based instance.
• Write to two separate, local influx databases. An example: The first database stores data with a high sampling rate with a retention policy that only keeps e.g. the last week or so, second database stores data with a low sample rate with an indefinite retention policy.

[leeprevost]

It seems like the second use case could be handled within Influx continuous queries (ver . 1.8) or tasks (>2.0). Also, influx ver 2 apparently supports a store/forward/synch service with their cloud service.

[tkurki]

See also https://github.com/tkurki/signalk-to-influxdb2