Connect to Apache Airflow Data from Blazor Apps

Blazor is a framework for developing modern, client-side web UIs using .NET technology. Instead of coding in JavaScript, developers can use the familiar C# language and .NET libraries to build app UIs.

The CData API Driver for ADO.NET can be used with standard ADO.NET interfaces, such as LINQ and Entity Framework, to interact with live Apache Airflow data. Since Blazor supports .NET Core, developers can use CData ADO.NET Providers in Blazor apps. In this article, we will guide you to build a simple Blazor app that talks to Apache Airflow using standard SQL queries.

Install the CData API Driver for ADO.NET

CData ADO.NET Providers allow users to access Apache Airflow just like they would access SQL Server, using simple SQL queries.

Install the Apache Airflow ADO.NET Data Provider from the CData website or from NuGet. Search NuGet for "Apache Airflow ADO.NET Data Provider."

Create a Apache Airflow-Connected Blazor App

Start by creating a Blazor project that references the CData API Driver for ADO.NET

1. Create a Blazor project on Visual Studio.

2. From the Solution Explorer, right click Dependencies, then click Add Project Reference.
3. In the Reference Manager, click the Browse button, and choose the .dll file of the installed ADO.NET Provider (e.g. System.Data.CData.API.dll, typically located at C:\Program Files\CData\CData API Driver for ADO.NET\lib etstandard2.0).

SELECT Apache Airflow Data from the Blazor App

1. Open the Index.razor file from the Project page.
2. In a APIConnection object, set the connection string:

   Start by setting the Profile connection property to the location of the ApacheAirflow Profile on disk (e.g. C:\profiles\ApacheAirflow.apip). Next, set the ProfileSettings connection property to the connection string for ApacheAirflow (see below).

   ApacheAirflow API Profile Settings

   Apache Airflow 3 uses JWT Bearer tokens for API authentication. You can generate a token from the Airflow web UI under Settings or via the Airflow CLI using airflow users create and the /api/v2/auth/token endpoint. Note that this profile targets Apache Airflow 3.x using the /api/v2 REST API. The legacy /api/v1 endpoint used by Airflow 2.x is not supported.

   After setting the following connection properties, you are ready to connect:

   • AuthScheme: Set this to APIKey.
   • APIKey: Set this to your Apache Airflow JWT Bearer token.
   • Server: Set this to the base URL of your Airflow instance (e.g. http://localhost:8080).

   For example: Profile=C:\profiles\ApacheAirflow.apip;AuthScheme=APIKey;ProfileSettings='APIKey=your_jwt_token;Server=http://localhost:8080';

3. The code below creates a simple Blazor app for displaying Apache Airflow data, using standard SQL to query Apache Airflow just like SQL Server.

         @page "/"
         @using System.Data;
         @using System.Data.CData.API;
         
         <h1>Hello, world!</h1>
         
         Welcome to your Data app.
         
         <div class="row">
             <div class="col-12">
         
                 @using (APIConnection connection = new APIConnection(
                   "Profile=C:\profiles\ApacheAirflow.apip;AuthScheme=APIKey;ProfileSettings='APIKey=your_jwt_token;Server=http://localhost:8080';"))
                 {
                     var sql = "SELECT DagRunId, State FROM DagRuns WHERE DagId = 'example_dag'";
                     var results = new DataTable();
         
                     APIDataAdapter dataAdapter = new APIDataAdapter(sql, connection);
                     dataAdapter.Fill(results);
         
                     <table class="table table-bordered">
                         <thead class="thead-light">
                             <tr>
                                 @foreach (DataColumn item in results.Rows[0].Table.Columns)
                                 {
                                     <th scope="col">@item.ColumnName</th>
                                 }
                             </tr>
                         </thead>
                         <tbody>
                             @foreach (DataRow row in results.Rows)
                             {
                                 <tr>
                                     @foreach (var column in row.ItemArray)
                                     {
                                         <td>@column.ToString()</td>
                                     }
                                 </tr>
                             }
                         </tbody>
                     </table>
                 }
             </div>
         </div>
       

4. Rebuild and run the project. The ADO.NET Provider renders Apache Airflow data as an HTML table in the Blazor app.

   At this point, you have a Apache Airflow-connected Blazor app, capable of working with live Apache Airflow data just like you would work with a SQL Server instance. Download a free, 30-day trial and start working with live Apache Airflow data in your Blazor apps today.