Sources

A source is where a module gets its data from. Each source provides one kind of data, and each module only takes sources of the kind it serves.

Which source fits which module

Source	Data	Fits	Install
entsoe_day_ahead	Day-ahead electricity prices	tariff, directive	entsoe
energy_cost	Prices from your own tariff	tariff, directive	energy-cost
energyid_production	Production of a meter	production, directive	energyid
acc_forecast	Forecast net volume of a connection, from EvO	simultaneity source, directive	acc
elia_solar_forecast	Solar forecast of a Belgian region	timeseries, directive	elia
ned_production_forecast	Production forecast of Dutch installations	timeseries, directive	ned
simultaneity	Simultaneity, from net volumes	simultaneity, directive	simultaneity
directive, dynamic_boundary_directive	Directive steps	directive	directive
demo_*	Generated data of every kind	every module	demo

“Install” is the extra to add: pip install "cofy-api[tariff,entsoe]", for example. Every source also fits the timeseries module, which serves any series as it is.

Credentials: secrets

A source that needs an API key or other credential takes a secret, referenced by name:

api_key: { type: secret, name: entsoe_key }

In the console, store the key in the community’s Secrets tab and pick it by name. In a settings file, list it under secrets:

secrets:
  - name: entsoe_key
    description: Our ENTSO-E Transparency Platform key.
    value: your-key

Sharing a source

A source configured once as a resource can be used by several modules. It is fetched once, so they share one cache:

resources:
  - type: source
    name: entsoe_be
    value:
      type: entsoe_day_ahead
      country_code: BE
      api_key: { type: secret, name: entsoe_key }
      cache: {}

modules:
  - type: tariff
    name: entsoe
    source: { type: resource, name: entsoe_be }
  - type: directive
    name: prices
    source:
      type: directive
      source: { type: resource, name: entsoe_be }
      boundaries: [0, 10, 25, 50]
      reverse: true

Caching

Without a cache, a source fetches its data again for every request. Give it a cache to keep what it fetched in memory:

Field	What it is
max_age	How long fetched data stays valid, as an ISO 8601 duration such as PT15M. The source’s own if left out.
chunk_size	The blocks of time fetched and kept together. A day, P1D, if left out.
max_chunks	How many blocks to keep, dropping the least recently used first. 1024 if left out.

cache: {} uses all defaults. That only works for sources that say how long their data stays valid, such as ENTSO-E, Elia and NED; each source page says so. For the others, give a max_age.

If fetching fresh data fails while older data is still in the cache, the older data is served rather than an error.