Country and Currency

In this example, we will create a Model file called CountryCurrency.json.

What we showcase in this example

• how to use the @@Seed property to read a CSV from an HTTP resource.
• how to build simple relationships between 2 Entities.

The source code

{
    "Model": {
        "Currency": {
            "Code": "String[3]",
            "Name": "Unicode",
            "NumericCode": "Int",

            "@@Seed": {
                "FromCsv": {
                    "Uri": "https://raw.githubusercontent.com/datasets/currency-codes/master/data/codes-all.csv",
                    "FirstLineIsHeader": true,
                    "MapHeaders": {
                        "Code": "AlphabeticCode",
                        "Name": "Currency",
                        "NumericCode": "NumericCode"
                    }
                }
            }
        },

        "Country": {
            "CountryName": "Unicode",
            "Alpha3": "String[3]",
            "CountryCode": "int",

            "@@Has": {
                "OfficialCurrency": "Currency"
            },

            "@@Seed": {
                "FromCsv": {
                    "Uri": "https://raw.githubusercontent.com/lukes/ISO-3166-Countries-with-Regional-Codes/master/all/all.csv",
                    "FirstLineIsHeader": true,
                    "MapHeaders": {
                        "CountryName": "name",
                        "Alpha3": "alpha-3",
                        "CountryCode": "country-code"
                    }
                }
            }
        }
    }
}

In the following example, we: - define an Entity called Currency with 3 Attributes: - Code of the type string with a maximum of length of 3. - Name of the type unicode indicating that it is a string that also supports unicode characters. - NumericCode of the type integer - use the special @@Seed property to specify that Currency has seed data, and that this data exists inside a CSV file located in a GitHub repository. - specify how the CSV data is mapped to each attribute using the MapHeaders property.