generated: '2026-07-27'
method: derived
source: openapi/chargy-open-charge-point-data-openapi.yml
description: >-
  Entity graph derived from the schemas of the char.gy Open Charge Point Data
  API. The feed is a two-collection model with one cross-collection reference:
  a connector points at a tariff by id, and that is the only join a consumer can
  make. There are no per-object endpoints, so every entity is reachable only by
  paging its parent collection.
entities:
  - name: Location
    collection: /locations
    identifier: id
    id_format: uuid
    count_observed: 5409
    key_fields: [country_code, party_id, id, parking_type, publish, name, address, city, postal_code, country, coordinates, time_zone, opening_times, last_updated]
    notes: >-
      party_id is always CGY and country_code always GB. parking_type was
      ON_STREET on every one of 250 sampled records — the lamp-post model.
  - name: EVSE
    embedded_in: Location
    identifier: uid
    business_identifier: evse_id
    id_format: 'uuid (uid); eMI3 GB*CGY*E*NNNNN (evse_id)'
    key_fields: [uid, evse_id, status, capabilities, connectors, physical_reference, last_updated]
  - name: Connector
    embedded_in: EVSE
    identifier: id
    id_format: 'ordinal string, e.g. "1"'
    key_fields: [id, standard, format, power_type, max_voltage, max_amperage, tariff_ids, terms_and_conditions, last_updated]
  - name: Tariff
    collection: /tariffs
    identifier: id
    id_format: uuid
    count_observed: 3
    key_fields: [country_code, party_id, id, currency, elements, last_updated]
  - name: TariffElement
    embedded_in: Tariff
    key_fields: [price_components, restrictions]
  - name: PriceComponent
    embedded_in: TariffElement
    key_fields: [type, price, step_size]
  - name: BusinessDetails
    embedded_in: Location
    roles: [operator, owner]
    key_fields: [name, website]
    notes: >-
      operator is always char.gy. owner is the local authority that owns the
      street furniture — Tower Hamlets, Southwark, Merton, Haringey and
      Buckinghamshire County Council were observed — and is absent on roughly
      40 percent of sampled records.
relationships:
  - from: Location
    to: EVSE
    type: has_many
    via: evses
    embedded: true
  - from: EVSE
    to: Connector
    type: has_many
    via: connectors
    embedded: true
  - from: Connector
    to: Tariff
    type: has_many
    via: tariff_ids
    embedded: false
    join: connector.tariff_ids[] == tariff.id
    note: >-
      The only cross-collection join in the model, and the only route from a
      charge point to its price. Consumers must fetch /tariffs separately and
      index it by id.
  - from: Location
    to: BusinessDetails
    type: has_one
    via: operator
    embedded: true
  - from: Location
    to: BusinessDetails
    type: has_one
    via: owner
    embedded: true
    optional: true
  - from: Location
    to: GeoLocation
    type: has_one
    via: coordinates
    embedded: true
  - from: Location
    to: Hours
    type: has_one
    via: opening_times
    embedded: true
  - from: Tariff
    to: TariffElement
    type: has_many
    via: elements
    embedded: true
  - from: TariffElement
    to: PriceComponent
    type: has_many
    via: price_components
    embedded: true
  - from: TariffElement
    to: TariffRestrictions
    type: has_one
    via: restrictions
    embedded: true
    optional: true
    note: >-
      Absence of restrictions means the price component applies at all times;
      the GBP tariff uses three elements to express weekday off-peak, weekday
      peak and weekend pricing.
access_notes:
  - No per-object read exists — GET /locations/{id} and /tariffs/{id} both 404.
  - >-
    No spatial, city, postcode or status filter exists, so any geographic query
    requires paging all 5,409 locations and filtering client-side.
  - >-
    date_from / date_to on last_updated are the only server-side filters, which
    makes incremental synchronisation practical even though targeted lookup is not.