Routing in Downlink

Downlink by default has a very aggressive route template: {version}/{platform?}/{arch?} meaning it will often match routes you didn't want it to.

To correct this, Downlink (since 0.2) includes support for prefixing the route template used for Downlink's actions.

Configuration

Tip

This method is also supported in the Docker image (even though it is not generally needed)

By default, Downlink will look for a configuration key called DownlinkPrefix and prepend the value of that to Downlink's action routes:

DownlinkPrefix: 'download'

{
    "DownlinkPrefix": "download"
}

This will change the template to download/{version}/{platform?}/{arch?}, effectively isolating Downlink form other routes in your application.

Code (for self-hosting)

If you're hosting Downlink, you can also add a prefix in your startup code:

// in Startup.cs
public void ConfigureServices(IServiceCollection services)
{
    services.AddMvc().AddDownlink(d => d.UseRoutePrefix("download"));
}

This will result in the same route template as the first example.

Internally, this is replacing the ConfigurationRoutePrefixBuilder with the StaticRoutePrefixBuilder.

Extensibility

This functionality is specifically designed for extensibility and is built around a super-simple IRoutePrefixBuilder interface:

string GetPrefix();

If you have your own implementation of the IRoutePrefixBuilder interface, register it using the UseRouteBuilder builder method and Downlink will invoke it instead on app start:

// in Startup.cs
public void ConfigureServices(IServiceCollection services)
{
    services.AddMvc().AddDownlink(d => d.UseRouteBuilder<MyAwesomeBuilder>());
}

Advanced extensibility

Warning

This is only recommended for advanced users who really know what they're doing: you can completely break your app this way.

If you need super-finegrained control over Downlink's routing behaviour, you can also re-implement the convention used for Downlink routing. This is mostly useful if you need to make non-trivial edits to the route template used by Downlink.

Downlink provides the IDownlinkRouteConvention interface to override the conventions applied on app start. If you register an implementation of IDownlinkRouteConvention in the Downlink builder, it will be added to the app's convention map and applied on app start.

Warning

Your IDownlinkRouteConvention implementation will be applied to the whole app, not just Downlink controllers and actions.

You can find the default convention implementation in DownlinkRouteConvention.