Business Central Integration with Rest API – OnPrem - Part 2

Dear Reader’s, I am sharing simple REST API integration with Business Central 2020 Wave 1 release. This is based on Part 1, where I have used both Codeunit & DotNet. Here I am using only codeunits to simulate same thing without DotNet variables.

Thanks to "Arend-Jan Kauffmann" reply where he has mentioned why you have used DotNet where it all will be handled by AL Data Types & Methods (Wrapper Classes). He has also share detailed explanation in his blog. So, inspired and reconstructed my Part 1 into two samples:

Example 1: (Sample 1) Used codeunits to handle the request & response without any DotNet variable combination.

Example 2: (Sample 2) Used AL Data Types & Methods (Wrapper Classes) to handle the request & response without using any Codeunit & DotNet varibale. This sample will run on SaaS model as well.

Example 1: Below are example of calling API without using DotNet variable:

codeunit 50102 "Json API Test2"

{

    trigger OnRun()

    begin

        // Plesase fix below line in single line

        Url := 'http://samples.openweathermap.org/data/2.5/weather?zip=110001,in&

                        appid=b6907d289e10d714a6e88b30761fae22';

        HttpWebRequestMgt.Initialize(Url);

        HttpWebRequestMgt.DisableUI();

        HttpWebRequestMgt.SetMethod('GET');

        HttpWebRequestMgt.SetReturnType('application/json');

        Clear(TempBlob);

        TempBlob.CreateInStream(InStr);

        IF HttpWebRequestMgt.GetResponseStream(InStr) then begin

            InStr.ReadText(Json, MaxStrLen(Json));

            Message(Json);

            IF JSONMgmt.InitializeFromString(Json) then begin

                Temperature := JSONMgmt.GetValue('main.temp');

                Pressure := JSONMgmt.GetValue('main.pressure');

                Humidity := JSONMgmt.GetValue('main.humidity');

                TempMin := JSONMgmt.GetValue('main.temp_min');

                TempMax := JSONMgmt.GetValue('main.temp_max');

            end;

            MESSAGE(Text001, Temperature, Pressure, Humidity, TempMin, TempMax);

        end;

    end;

    var

        HttpWebRequestMgt: Codeunit "Http Web Request Mgt.";

        Url: Text;

        Json: Text;

        TempBlob: Codeunit "Temp Blob";

        InStr: InStream;

        Temperature: Text;

        Pressure: Text;

        Humidity: Text;

        TempMin: Text;

        TempMax: Text;

        JSONMgmt: Codeunit "JSON Management";

        // Plesase fix below line in single line

        Text001: Label 'Temperature: %1 \Pressure: %2 \Humidity: %3 

                            \Min Temperature: %4 \Max  Temperature: %5';

}

Example 2: (Sample 2) Using AL Data Types & Methods (Wrapper Classes) 

codeunit 50104 "Json API Test4"

{

    trigger OnRun()

    begin

        
        // Plesase fix below line in single line

        Url := 'http://samples.openweathermap.org/data/2.5/weather?zip=110001,in

                        &appid=b6907d289e10d714a6e88b30761fae22';

        HttpHeader := HttpWebClient.DefaultRequestHeaders;

        HttpHeader.Add('Accept', 'application/json');

        IF HttpWebClient.Get(Url, HttpWebResponse) then

            IF HttpWebResponse.IsSuccessStatusCode then begin

                HttpWebResponse.Content.ReadAs(Json);

                Message(Json);

                JObject.ReadFrom(Json);

                IF JObject.SelectToken('main.temp', JToken) then

                    Temperature := JToken.AsValue().AsText();

                IF JObject.SelectToken('main.pressure', JToken) then

                    Pressure := JToken.AsValue().AsText();

                IF JObject.SelectToken('main.humidity', JToken) then

                    Humidity := JToken.AsValue().AsText();

                IF JObject.SelectToken('main.temp_min', JToken) then

                    TempMin := JToken.AsValue().AsText();

                IF JObject.SelectToken('main.temp_max', JToken) then

                    TempMax := JToken.AsValue().AsText();

                MESSAGE(Text001, Temperature, Pressure, Humidity, TempMin, TempMax);

            end;

    end;

    var

        Url: Text;

        Json: Text;

        Temperature: Text;

        Pressure: Text;

        Humidity: Text;

        TempMin: Text;

        TempMax: Text;

        HttpWebClient: HttpClient;

        HttpHeader: HttpHeaders;

        HttpWebResponse: HttpResponseMessage;

        JObject: JsonObject;

        JToken: JsonToken;

// Plesase fix below line in single line

        Text001: Label 'Using Wrapper Class:\Temperature: %1 \Pressure: %2 

            \Humidity: %3 \Min Temperature: %4 \Max  Temperature: %5';

}

Stay tuned, next blog is coming soon...