Money.ExchangeRates.OpenExchangeRates (Money v6.1.0)

Implements the Money.ExchangeRates for the Open Exchange Rates service.

Required configuration:

The configuration key :open_exchange_rates_app_id should be set to your app_id. For example:

config :ex_money,
  open_exchange_rates_app_id: "your_app_id"

or configure it via environment variable:

config :ex_money,
  open_exchange_rates_app_id: {:system, "OPEN_EXCHANGE_RATES_APP_ID"}

It is also possible to configure an alternative base url for this service in case it changes in the future. For example:

config :ex_money,
  open_exchange_rates_app_id: "your_app_id"
  open_exchange_rates_url: "https://openexchangerates.org/alternative_api"

Summary

Functions

get_historic_rates(date, config)

Retrieves the historic exchange rates from Open Exchange Rates site.

get_latest_rates(config)

Retrieves the latest exchange rates from Open Exchange Rates site.

init(default_config)

Update the retriever configuration to include the requirements for Open Exchange Rates. This function is invoked when the exchange rate service starts up, just after the ets table :exchange_rates is created.

Functions

get_historic_rates(date, config)

Retrieves the historic exchange rates from Open Exchange Rates site.

date is a Date.t/0 or any date-compatible map or struct (Calendar.date/0).
config is the retrieval configuration. When invoked from the exchange rates service this will be the config returned from Money.ExchangeRates.config/0

Returns:

{:ok, rates} if the rates can be retrieved
{:ok, :not_modified} if the rates are unchanged since the last retrieval
{:error, reason} if rates cannot be retrieved

Typically this function is called by the exchange rates retrieval service although it can be called outside that context as required.

get_latest_rates(config)

Retrieves the latest exchange rates from Open Exchange Rates site.

config is the retrieval configuration. When invoked from the exchange rates service this will be the config returned from Money.ExchangeRates.config/0

Returns:

{:ok, rates} if the rates can be retrieved
{:ok, :not_modified} if the rates are unchanged since the last retrieval
{:error, reason} if rates cannot be retrieved

Typically this function is called by the exchange rates retrieval service although it can be called outside that context as required.

init(default_config)

Update the retriever configuration to include the requirements for Open Exchange Rates. This function is invoked when the exchange rate service starts up, just after the ets table :exchange_rates is created.

default_config is the configuration returned by Money.ExchangeRates.default_config/0

Returns the configuration either unchanged or updated with additional configuration specific to this exchange rates retrieval module.