mnb.hu-apicalls-test

Some test calls to the Hungarian central bank's API (Magyar Nemzeti Bank, "Hungarian National Bank").

The API is a public SOAP API.

Requirements

• Python ^3.8
• Poetry

Notes, how-tos

List available operations from the API

First, get an overview of all available operations and their call signatures:

python -mzeep https://www.mnb.hu/arfolyamok.asmx?wsdl

Response:

Service: MNBArfolyamServiceSoapImpl
     Port: CustomBinding_MNBArfolyamServiceSoap (Soap11Binding: {http://tempuri.org/}CustomBinding_MNBArfolyamServiceSoap)
         Operations:
            GetCurrencies() -> GetCurrenciesResult: xsd:string
            GetCurrencyUnits(currencyNames: xsd:string) -> GetCurrencyUnitsResult: xsd:string
            GetCurrentExchangeRates() -> GetCurrentExchangeRatesResult: xsd:string
            GetDateInterval() -> GetDateIntervalResult: xsd:string
            GetExchangeRates(startDate: xsd:string, endDate: xsd:string, currencyNames: xsd:string) -> GetExchangeRatesResult: xsd:string
            GetInfo() -> GetInfoResult: xsd:string

The zeep library use the first defined service by default. Some example calls:

result = client.service.GetCurrencies()
result = client.service.GetInfo()
result = client.service.GetCurrencyUnits('EUR')

Converting the returned data

The zeep should convert the XML from the API into a dict but the API somehow returns an invalid/incomplete XML.

I use the xmltodict library manages to do it.

I then structure the data the way I want in the prepare_data() function.

The data converted into JSON looks like this (extract only):

{
    "date": "2021-09-28",
    "rates": {
        "AUD": {
            "unit": "1",
            "value": "223,72"
        },
        "BGN": {
            "unit": "1",
            "value": "183,76"
        },
        "BRL": {
            "unit": "1",
            "value": "57,06"
        },
        "JPY": {
            "unit": "100",
            "value": "276,48"
        }
    }
}

This allows me to access the results this way:

print(final_dict["rates"]["AUD"])
{'unit': '1', 'value': '223,72'}
# 1 AUD = 223,72 HFU

print(final_dict["rates"]["JPY"])
{'unit': '100', 'value': '276,48'}
# 100 JPY = 276,48 HFU

The data structure is of course modifiable.