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Develop a .NET Custom Data Provider

A .NET Custom Data Provider

A custom .NET data connector is required .NET8 SDK and the steps to create it involve creating a library project in Visual Studio, referencing the Wyn assembly (Wyn.Data.Provider.Custom.dll) and the NuGet package of the data source, and finally, writing a class that implements a single interface (Wyn.Data.Provider.Custom.dll.INativeQueryDataProvider) which includes few properties and methods.

Here are the step-by-step instructions on how to build an example custom data provider for Firebird.

Developing a Firebird Data Source

Create a Visual Studio Project

  1. Create a Class Library project in Visual Studio.


    VSnewproject


  2. Choose a class library project.


    VSConfigureProject


Reference the Custom Provider Library

Search on Nuget and add the Wyn.Data.Provider.Custom package to the project.


Wyn.Data.Provider.Custom

Reference the Firebird Client library

Similarly, search for and add the FirebirdSql.Data.FirebirdClient NuGet package to the project.


VSProviderDependency

Add Project Resources

  1. Three resource files should be added to the project:

  • A small 16x16 icon that is shown in Wyn

  • A large 180x130 icon is shown in Wyn.

  • A markdown file named UserGuide.md file. This file explains how to add information about the database and the connection string.


    To complete the Firebird example project, download these three resources from the link below.


    .NET Firebird Sample


    Add Project Resources


  1. Select these resource files in the Visual Studio project and set Output Directory "Copy Always" in the properties window.


    Solution explorer


Implement the Interface in the Main class

The main class of the project should implement the INativeQueryDataProvider interface.


For the Firebird example, you can replace the content of the class with the complete example code below.


Implement the interface in the main class

Implement the Interface

Implement the methods in the FirebirdProvider class.

using FirebirdSql.Data.FirebirdClient; 
using Wyn.Data.Provider.Custom;
using System.Data;
using System.Reflection;

namespace FirebirdProvider
{
    public class FirebirdProvider : INativeQueryDataProvider
    {
        public static string ProviderName => "Firebird";

        public static void Configure(IFeatureCollection features)
        {
            features.Metadata().DisplayName = ProviderName;
            features.Metadata().Description = "This is Firebird provider.";

            var assemblyDirectory = Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location);
            if (Path.Combine(assemblyDirectory!, "UserGuide.md") is var userGuidePath && File.Exists(userGuidePath))
            {
                features.UserGuide().UserGuideMarkdown = File.ReadAllText(userGuidePath);
            }

            if (Path.Combine(assemblyDirectory!, "firebird_16x16.png") is var smallIconPath && File.Exists(smallIconPath))
            {
                features.Metadata().SmallIcon = GetDataURL(smallIconPath);
            }

            if (Path.Combine(assemblyDirectory!, "firebird_180x130.png") is var largeIconPath && File.Exists(largeIconPath))
            {
                features.Metadata().LargeIcon = GetDataURL(largeIconPath);
            }

            static string GetDataURL(string imgFilePath)
            {
                return "data:image/png;base64," + Convert.ToBase64String(File.ReadAllBytes(imgFilePath));
            }

            features.Get<IParameterParseFeature>().NeedFillParameters = false;
        }

        public static INativeQueryDataProvider CreateInstance() => new FirebirdProvider();

        public async Task ExecuteAsync(INativeQuery nativeQuery, Action<IDataReader> readerConsumer, params NativeParameter[] parameters)
        {
            using var connection = new FbConnection(nativeQuery.ConnectionString);
            await connection.OpenAsync();
            var command = connection.CreateCommand();
            command.CommandText = nativeQuery.QueryText;
            foreach (var parameter in parameters)
            {
                var para = command.CreateParameter();
                para.ParameterName = parameter.Name;
                para.Value = parameter.ParameterValue;
                command.Parameters.Add(para);
            }
            readerConsumer(await command.ExecuteReaderAsync());
        }

        public async Task TestConnectionAsync(string connectionString)
        {
            using var connection = new FbConnection(connectionString);
            await connection.OpenAsync();
        }
    }
}

Implement the Interface

Publish the project to generate the artifact file.

Right-click the project name in Visual Studio. Choose a target folder and click "Publish" to publish your project.


VSPublishArtifacts


Publish

Send to the Wyn Administrator

Zip the published artifacts folder and send it to the Wyn Server administrator to deploy to the Wyn Server machine. If you are the administrator, the instructions to deploy the custom connector and configure Wyn is in the Deploy and Configure a Custom Data Source.