To upload a new observation to Helios, we make a POST request to the Create method in the Observations API. We can send an unlimited number of sensor measurements with each upload and all sensor values will be associated with a single observation.

The following curl command shows how we can submit a multipart/form request to create a new observation with an image attachment:

curl -X POST https://api.helios.earth/v1/observations \
-H "Authorization: Bearer <...my access token...>"
--form image=@preview.jpg \
--form time=2017-08-01T12:34:56Z \
--form description="Test observation upload" \
--form longitude=-77.0 \
--form latitude=43.0 \
--form sensors[temperature_celcius][data]=18.5 \
--form sensors[humidity][data]=0.56

As shown in this example, we can send our nested metadata values using a square bracket syntax.