Dan.Plugin.Sjofart

Plugin for integrations towards Sjøfartsdirektoratet

Adding mapping for new documents

When calling Sjøfartsdirektoratet's API for vessel data, it contains a collection of Document objects. These documents do not share the same format, meaning they can't be reasonably deserialised into a simple POCO. To manage this, a custom JsonConverter has been made VesselDocumentConverter. Using the Document Classes found in the VesselDocuments folder, this converter can determine what class to deserialise to as long as the Document Class has been implemented correctly.

Let's make an example class for a document:

{
    "CertificateOfNationalityDate": "2012.03.20",
    "SrMeasurementData": {
        "ClassificationSociety": "Anonymised",
        "MeasurementCertificateCountry": "Anonymised",
        "VesselType": "STYKKGODSSKIP: - UBESTEMT",
        "BuildMaterial": "STÅL",
        "Propulsion": "MOTOR",
        "Length": {
            "Value": 81.07,
            "Unit": "METER"
        },
        "Width": {
            "Value": 12.8,
            "Unit": "METER"
        },
        "Depth": {
            "Value": 7.1,
            "Unit": "METER"
        },
        "GrossTonnage": 2528.0,
        "NetTonnage": 1372.0,
        "NISApprovedDate": "2012.02.16",
        "SeaworthyDate": "2012.02.16"
    },
    "Register": "Norsk Internasjonalt Skipsregister",
    "IsConferred": true,
    "DocumentTypeClass": "TE",
    "DocumentType": "MÅLEBREV",
    "JournalDate": "2012.03.20",
    "Date": "2000.06.22",
    "JournalKey": "Anonymised"
}

The identifiers for vessel documents are "DocumentTypeClass" and "DocumentType". The class we make needs to implement the interface IDocumentIdentifiable where we set these values. The class also needs to implement IVesselDocument, the VesselDocument class is an abstract class that implements the interface that can be used too.

So with that we can make a class that looks like:

[Serializable]
public class MeasurementDataDocument : VesselDocument, IDocumentIdentifiable
{
    public static string DocumentTypeClassIdentifier => "TE";
    public static string[] DocumentTypeIdentifiers => ["MÅLEBREV"];
}

The DocumentTypeIdentifiers is an array, because the same document can sometimes have different DocumentTypes. For Measurement Data Documents, "MÅLEDATA" is another value that is sometimes used, so we can add that to the array.

[Serializable]
public class MeasurementDataDocument : VesselDocument, IDocumentIdentifiable
{
    public static string DocumentTypeClassIdentifier => "TE";
    public static string[] DocumentTypeIdentifiers => ["MÅLEBREV", "MÅLEDATA"];
}

As long as those two static properties are set correctly, the rest can be implemented as a normally expected. In this case we are interested in some of the data found in the SrMeasurementData property.

[Serializable]
public class MeasurementDataDocument : VesselDocument, IDocumentIdentifiable
{
    public static string DocumentTypeClassIdentifier => "TE";
    public static string[] DocumentTypeIdentifiers => ["MÅLEBREV", "MÅLEDATA"];

    [JsonPropertyName("SrMeasurementData")]
    public SrMeasurementData SrMeasurementData { get; set; }
}

Finally, the ResponseModelMapper must be updated to map the data from the new document to the ResponseModel class.