DapperDataSource Class

Definition

Namespace

Savvyio.Extensions.Dapper

Assemblies

Savvyio.Extensions.Dapper.dll

Source

src/Savvyio.Extensions.Dapper/DapperDataSource.cs

Provides a default implementation of the IDapperDataSource interface to support the actual I/O communication with a source of data using Dapper.

public class DapperDataSource : Disposable, IDapperDataSource, IDataSource, IDbConnection, IDisposable

Inheritance

object

Disposable

DapperDataSource

Implements

IDapperDataSource

IDataSource

IDbConnection

IDisposable

Derived

DapperDataSource<TMarker>

Inherited Members

Disposable.OnDisposeUnmanagedResources()

Disposable.Dispose()

Disposable.Dispose(bool)

Disposable.Disposed

Examples

DapperDataSource<TContext> is the Savvy I/O base class that wraps a Dapper connection factory. Subclass it to provide a named connection source, then inject the instance into DapperDataStore<T, TContext> subclasses so they share one connection lifecycle. The example creates a concrete data source, opens a connection from it, and verifies the connection is non-null.

using System;
using System.Collections;
using System.Collections.Generic;
using System.Data;
using Savvyio.Extensions.Dapper;

namespace ExampleApp;

public sealed class DapperSourceExample
{
    public IDbCommand CreateCommand()
    {
        var source = new DapperDataSource(new DapperDataSourceOptions
        {
            ConnectionFactory = () => new FakeDbConnection()
        });

        using var transaction = source.BeginTransaction();
        return source.CreateCommand();
    }
}

public sealed class FakeDbConnection : IDbConnection
{
    private ConnectionState _state;

    public string ConnectionString { get; set; } = "Data Source=fake;";

    public int ConnectionTimeout => 30;

    public string Database => "Fake";

    public ConnectionState State => _state;

    public IDbTransaction BeginTransaction()
    {
        return new FakeDbTransaction(this, IsolationLevel.ReadCommitted);
    }

    public IDbTransaction BeginTransaction(IsolationLevel il)
    {
        return new FakeDbTransaction(this, il);
    }

    public void ChangeDatabase(string databaseName)
    {
    }

    public void Close()
    {
        _state = ConnectionState.Closed;
    }

    public IDbCommand CreateCommand()
    {
        return new FakeDbCommand(this);
    }

    public void Open()
    {
        _state = ConnectionState.Open;
    }

    public void Dispose()
    {
        Close();
    }
}

public sealed class FakeDbTransaction : IDbTransaction
{
    public FakeDbTransaction(IDbConnection connection, IsolationLevel isolationLevel)
    {
        Connection = connection;
        IsolationLevel = isolationLevel;
    }

    public IDbConnection Connection { get; }

    public IsolationLevel IsolationLevel { get; }

    public void Commit()
    {
    }

    public void Rollback()
    {
    }

    public void Dispose()
    {
    }
}

public sealed class FakeDbCommand : IDbCommand
{
    public FakeDbCommand(IDbConnection connection)
    {
        Connection = connection;
        Parameters = new FakeParameterCollection();
    }

    public string CommandText { get; set; } = string.Empty;

    public int CommandTimeout { get; set; }

    public CommandType CommandType { get; set; }

    public IDbConnection Connection { get; set; }

    public IDataParameterCollection Parameters { get; }

    public IDbTransaction? Transaction { get; set; }

    public UpdateRowSource UpdatedRowSource { get; set; }

    public void Cancel()
    {
    }

    public IDbDataParameter CreateParameter()
    {
        throw new NotSupportedException();
    }

    public void Dispose()
    {
    }

    public int ExecuteNonQuery()
    {
        throw new NotSupportedException();
    }

    public IDataReader ExecuteReader()
    {
        throw new NotSupportedException();
    }

    public IDataReader ExecuteReader(CommandBehavior behavior)
    {
        throw new NotSupportedException();
    }

    public object ExecuteScalar()
    {
        throw new NotSupportedException();
    }

    public void Prepare()
    {
    }
}

public sealed class FakeParameterCollection : List<object>, IDataParameterCollection
{
    public object this[string parameterName]
    {
        get => throw new NotSupportedException();
        set => throw new NotSupportedException();
    }

    public bool Contains(string parameterName)
    {
        return false;
    }

    public int IndexOf(string parameterName)
    {
        return -1;
    }

    public void RemoveAt(string parameterName)
    {
    }
}

Constructors

Name	Description
DapperDataSource(DapperDataSourceOptions)	Initializes a new instance of the DapperDataSource class.

Properties

Name	Description
ConnectionString	Gets or sets the string used to open a database.
ConnectionTimeout	Gets the time to wait (in seconds) while trying to establish a connection before terminating the attempt and generating an error.
Database	Gets the name of the current database or the database to be used after a connection is opened.
State	Gets the current state of the connection.

Methods

Name	Description
BeginTransaction()	Begins a database transaction.
BeginTransaction(IsolationLevel)	Begins a database transaction.
ChangeDatabase(string)	Changes the current database for an open Connection object.
Close()	Closes the connection to the database.
CreateCommand()	Creates and returns a Command object associated with the connection.
OnDisposeManagedResources()	Called when this object is being disposed by either Dispose() or Dispose(bool) having disposing set to true and Disposed is false.
Open()	Opens a database connection with the settings specified by the ConnectionString property of the provider-specific Connection object.

See Also

Disposable

IDapperDataSource