gRPC Microservices example using .NET6 Gateway gRPC stub and .NET 6 gRPC Server

gRPC is a RPC protocol using HTTP/2 as transport layer and sending/recieving messages using Protobuf.

In this example we have a .NET 6 API Gateway which acts a gRPC stub and .NET 6 gRPC server connected to Azure Postgres SQL for persistence.

In this example we implement 5 restful API(s) which make a gRPC call to the gRPC server.

• /api/Products?v=1&searchAfter=2023-02-16T09:52:57.6046760Z&limit=100 (HTTP GET)
• /api/Products/2e2c4a74-a6d2-4c79-ad1f-a5e9bdc7a005?v=1 (HTTP GET)
• /api/Products (HTTP POST)
• /api/Products/2e2c4a74-a6d2-4c79-ad1f-a5e9bdc7a005?v=1 (HTTP PUT)
• /api/Products/2e2c4a74-a6d2-4c79-ad1f-a5e9bdc7a005?v=1 (HTTP DELETE)

Following is a high-level flow diagram between the client, gRPC client stub api and the gRPC server.

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To Run

Pre-requisites -

• Provision a Azure Postgres SQL with the following settings mentioned here.
• Install Postman for testing gRPC
• Add server reflection to exposing services metadata to be detected to Postman.
• Install Azure Data Studio
• Run seed script.

Server side configurations -

dotnet new sln
mkdir src
cd src

dotnet new grpc -o Api --Framework net6.0
dotnet new classlib -o Domain --framework=net6.0
dotnet new classlib -o Infrastructure --framework=net6.0

dotnet sln add .\src\Api
dotnet sln add .\src\Domain
dotnet sln add .\src\Infrastructure

Install the following nuget packages to work with the gRPC server and connect to Azure Postgres SQL.

• Grpc.AspNetCore
• Grpc.Tools
• AutoMapper
• AutoMapper.Extensions.Microsoft.DependencyInjection
• Dapper
• Npgsql

We can share the .proto file with the client so that the client can generate the code.

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Client side configurations -

dotnet new sln
mkdir src
cd src

dotnet new webapi -o Api --framework=net6.0
dotnet new classlib -o Domain --framework=net6.0
dotnet new classlib -o Application --framework=net6.0
dotnet new classlib -o Infrastructure --framework=net6.0

dotnet sln add .\src\Api
dotnet sln add .\src\Domain
dotnet sln add .\src\Application
dotnet sln add .\src\Infrastructure

Install the following nuget packages to work with the gRPC stub client.

• Google.Protobuf
• Grpc.Net.Client
• Grpc.Tools
• Microsoft.AspNetCore.Mvc.NewtonsoftJson
• Microsoft.AspNetCore.Mvc.Versioning
• MediatR
• AutoMapper
• AutoMapper.Extensions.Microsoft.DependencyInjection
• FluentValidation
• FluentValidation.AspNetCore
• FluentValidation.DependencyInjectionExtensions

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To deploy gRPC server in Azure App Service -

• Provision a Linux Azure App Service targetting runtime .NET 6 LTS or .NET 7 STS
• Enable the options in the configuration section of the Azure App Service
• Add the same port number of https which is present in the launchSettings.json file in the HTTP20_ONLY_PORT configuration.
• For more details check out the official documentation here.