GenericHost.DistanceMatrix

GenericHost.DistanceMatrix

Console app built on the .NET Generic Host that resolves an application service from the container and uses it to compute travel distance and duration between two places via the Distance Matrix API.

This is the dedicated showcase for the GoogleMapsApi.Extensions.DependencyInjection package: IGoogleMapsClient is registered once with AddGoogleMaps(...) and the ambient API key is bound from configuration, so TravelTimeService depends only on IGoogleMapsClient and never sees the key or an HttpClient.

Run

GOOGLE_API_KEY=your_api_key dotnet run --project samples/GenericHost.DistanceMatrix -- "New York, NY" "Boston, MA"

Omit the origin/destination args and it defaults to New York → Boston.

The API key resolves from (in order):

1. The GOOGLE_API_KEY environment variable (mapped into GoogleMaps:ApiKey in Program.cs).
2. The GoogleMaps:ApiKey configuration value — appsettings.json, user secrets, or a GoogleMaps__ApiKey environment variable.

What this demonstrates

• AddGoogleMaps(IConfiguration) — binds GoogleMapsClientOptions (the ambient API key) from a config section
• Constructor injection of IGoogleMapsClient into a regular application service
• Host.CreateApplicationBuilder generic-host wiring with IServiceCollection and ILogger<T>
• DistanceMatrixRequest / DistanceMatrixResponse with requests that carry no API key — it comes from DI

The Minimal API sample uses the AddGoogleMaps(Action<GoogleMapsClientOptions>) overload instead; this sample uses the configuration-binding overload.