# Extending - Loaders

It's very easy to add custom providers. Remember that .NET creates a <mark style="color:blue;">**ConfigurationSource**</mark> that implements and returns a <mark style="color:blue;">**ConfigurationProvider**</mark>.&#x20;

You can see this pattern here: [Implement a custom configuration provider](https://docs.microsoft.com/en-us/dotnet/core/extensions/custom-configuration-provider).

### Custom Implementation

To implement a custom source and provider only requires a single line of code.

1. Call the ConfigureConfiguration method.&#x20;
2. This callback sends you two parameters:
   1. <mark style="color:blue;">**IConfigurationBuilder**</mark> This builder allows you to add a custom source.
   2. <mark style="color:blue;">**EnivronmentString**</mark> the string variable that is the current environment.&#x20;
3. Simply add a new instance of the source. (See **line 5**)

{% code lineNumbers="true" %}

```csharp
PerigeeApplication.ApplicationNoInit("DemoApp", (c) => {
    
    //Add ConfigurationSource to the builder
    c.ConfigureConfiguration((builder, EnvStr) => {
        builder.Add(new SQLConfigurationSource("connectionString", "select [name], [value] from dbo.configs", "sql"));
    });

    //Reload all providers
    c.ReloadProviders();

    //Reload the specific provider
    c.ReloadProvidersOfType(typeof(SQLConfigurationProvider));
    
    string MyValueFromSQL = c.GetValue<string>("sql:MyValue");
    
});
```

{% endcode %}

You can see how easy it is in the future to reload the providers. You can reload all of them or specific types by supplying that type information.

### Using the built in SQL Provider

If you're trying to load values from a SQL database, then Perigee ships with a loader ready to go in only a single line of code. Simply call the configuration method and supply the connection, query, and prefix.&#x20;

{% hint style="success" %}
Because this works with `IDBConnection`, it works with MSSQL, PostGres, MySql... etc. Just supply the appropriate connection and it will work!
{% endhint %}

{% code overflow="wrap" %}

```csharp
PerigeeApplication.ApplicationNoInit("DemoApp", (c) => {

    //Configure the SQL Property loader using SqlConnection
    c.ConfigureSqlPropertyLoader(
        () => new SqlConnection(c.GetConnectionString("main")),
        "SELECT [Key],[Value] FROM [dbo].[PropertyStore]");

    string MyValueFromSQL = c.GetValue<string>("sql:MyValue");
    
});
```

{% endcode %}


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