Integration and Web Services

Expose BC data via web services, call external APIs with HttpClient, and import/export data with XmlPorts.

35 minAdvanced

Learning Objectives

Publish SOAP and OData web services from AL codeunits
Call external REST APIs using HttpClient
Import and export data with XmlPort objects

Web Services in Business Central

BC exposes data via SOAP and OData web services. Publish codeunits, pages, or queries as web services from the BC admin.

Service-Enabled Codeunit

CustomerWebService.Codeunit.al

codeunit 50100 "Customer Web Service"
{
    [ServiceEnabled]
    procedure GetCustomerBalance(CustomerNo: Code[20]): Decimal
    var
        Customer: Record Customer;
    begin
        if Customer.Get(CustomerNo) then
            exit(Customer."Balance (LCY)");
        Error('Customer %1 not found.', CustomerNo);
    end;
}

Publish this codeunit as a web service in BC: Web Services page → New → Object Type: Codeunit.

Calling External APIs

Use HttpClient to integrate with external systems:

ExternalAPI.Codeunit.al

procedure CallExternalAPI(): Text
var
    HttpClient: HttpClient;
    HttpResponseMessage: HttpResponseMessage;
    HttpHeaders: HttpHeaders;
    JsonResponse: Text;
begin
    HttpClient.DefaultRequestHeaders().Add('Authorization', 'Bearer ' + GetApiToken());
    HttpClient.Get('https://api.example.com/customers', HttpResponseMessage);

    if HttpResponseMessage.IsSuccessStatusCode then begin
        HttpResponseMessage.Content.ReadAs(JsonResponse);
        exit(JsonResponse);
    end else
        Error('API call failed with status %1', HttpResponseMessage.HttpStatusCode);
end;

Security

Never hardcode API keys in AL code. Use Isolated Storage or Azure Key Vault for secrets.

OData and API Pages

Modern integrations use API Pages (OData v4):

BonusAPI.Page.al

page 50100 "Bonus API"
{
    PageType = API;
    APIPublisher = 'navbc';
    APIGroup = 'learning';
    APIVersion = 'v1.0';
    EntityName = 'customerBonus';
    EntitySetName = 'customerBonuses';
    SourceTable = "Customer Bonus";
    DelayedInsert = true;

    layout
    {
        area(Content)
        {
            field(id; Rec."Entry No.") { }
            field(customerNo; Rec."Customer No.") { }
            field(amount; Rec."Bonus Amount") { }
        }
    }
}

XmlPort for Data Exchange

Import/export data in XML, CSV, or fixed-width formats:

CustomerImport.XmlPort.al

xmlport 50100 "Customer Import"
{
    Direction = Import;
    Format = VariableText;

    schema
    {
        textelement(Root)
        {
            tableelement(Customer; Customer)
            {
                fieldelement(No; Customer."No.") { }
                fieldelement(Name; Customer.Name) { }
            }
        }
    }
}

Integration Patterns

Pattern	Use Case
API Pages (OData)	Modern REST integrations, Power Platform
SOAP Web Services	Legacy system integrations
HttpClient	Call external REST/JSON APIs
XmlPort	File-based import/export, EDI
Event Subscribers	React to BC events for sync triggers

Key Revision Points (MB-820)

[ServiceEnabled] exposes codeunit procedures as web services
HttpClient for outbound API calls
API Pages are the modern OData integration approach
XmlPorts handle file-based data exchange