gRPC services can be hosted on ASP.NET Core. Services have full integration with ASP.NET Core features such as logging, dependency injection (DI), authentication, and authorization.
### Add gRPC services to an ASP.NET Core app
gRPC requires the [Grpc.AspNetCore](https://www.nuget.org/packages/Grpc.AspNetCore) package. For information on configuring gRPC in a .NET app, see [Configure gRPC](xref:grpc/aspnetcore#configure-grpc).
`GreeterService` inherits from the `GreeterBase` type, which is generated from the `Greeter` service in the *\*.proto* file. The service is made accessible to clients in *Program.cs*:
To learn more about gRPC services on ASP.NET Core, see <xref:grpc/aspnetcore>.
## Call gRPC services with a .NET client
gRPC clients are concrete client types that are [generated from *\*.proto* files](xref:grpc/basics#generated-c-assets). The concrete gRPC client has methods that translate to the gRPC service in the *\*.proto* file.
```csharp
var channel = GrpcChannel.ForAddress("https://localhost:5001");
A gRPC client is created using a channel, which represents a long-lived connection to a gRPC service. A channel can be created using `GrpcChannel.ForAddress`.
For more information on creating clients, and calling different service methods, see <xref:grpc/client>.
* Contract-first API development, using Protocol Buffers by default, allowing for language agnostic implementations.
* Tooling available for many languages to generate strongly-typed servers and clients.
* Supports client, server, and bi-directional streaming calls.
* Reduced network usage with Protobuf binary serialization.
These benefits make gRPC ideal for:
* Lightweight microservices where efficiency is critical.
* Polyglot systems where multiple languages are required for development.
* Point-to-point real-time services that need to handle streaming requests or responses.
[!INCLUDE[](~/includes/gRPCazure.md)]
## C# Tooling support for .proto files
gRPC uses a contract-first approach to API development. Services and messages are defined in *\*.proto* files:
```protobuf
syntax = "proto3";
service Greeter {
rpc SayHello (HelloRequest) returns (HelloReply);
}
message HelloRequest {
string name = 1;
}
message HelloReply {
string message = 1;
}
```
.NET types for services, clients, and messages are automatically generated by including *\*.proto* files in a project:
* Add a package reference to [Grpc.Tools](https://www.nuget.org/packages/Grpc.Tools/) package.
* Add *\*.proto* files to the `<Protobuf>` item group.
```xml
<ItemGroup>
<ProtobufInclude="Protos\greet.proto"/>
</ItemGroup>
```
For more information on gRPC tooling support, see <xref:grpc/basics>.
## gRPC services on ASP.NET Core
gRPC services can be hosted on ASP.NET Core. Services have full integration with ASP.NET Core features such as logging, dependency injection (DI), authentication, and authorization.
### Add gRPC services to an ASP.NET Core app
gRPC requires the [Grpc.AspNetCore](https://www.nuget.org/packages/Grpc.AspNetCore) package. For information on configuring gRPC in a .NET app, see [Configure gRPC](xref:grpc/aspnetcore#configure-grpc).
### The gRPC service project template
The gRPC service project template provides a starter service:
```csharp
public class GreeterService : Greeter.GreeterBase
{
private readonly ILogger<GreeterService> _logger;
public GreeterService(ILogger<GreeterService> logger)
{
_logger = logger;
}
public override Task<HelloReply> SayHello(HelloRequest request,
ServerCallContext context)
{
_logger.LogInformation("Saying hello to {Name}", request.Name);
return Task.FromResult(new HelloReply
{
Message = "Hello " + request.Name
});
}
}
```
`GreeterService` inherits from the `GreeterBase` type, which is generated from the `Greeter` service in the *\*.proto* file. The service is made accessible to clients in *Startup.cs*:
```csharp
app.UseEndpoints(endpoints =>
{
endpoints.MapGrpcService<GreeterService>();
});
```
To learn more about gRPC services on ASP.NET Core, see <xref:grpc/aspnetcore>.
## Call gRPC services with a .NET client
gRPC clients are concrete client types that are [generated from *\*.proto* files](xref:grpc/basics#generated-c-assets). The concrete gRPC client has methods that translate to the gRPC service in the *\*.proto* file.
```csharp
var channel = GrpcChannel.ForAddress("https://localhost:5001");
var client = new Greeter.GreeterClient(channel);
var response = await client.SayHelloAsync(
new HelloRequest { Name = "World" });
Console.WriteLine(response.Message);
```
A gRPC client is created using a channel, which represents a long-lived connection to a gRPC service. A channel can be created using `GrpcChannel.ForAddress`.
For more information on creating clients, and calling different service methods, see <xref:grpc/client>.
