![\"\"](\"https:\/\/magdy.dev\/blog\/wp-content\/uploads\/2019\/06\/grpc_image.png\")
gRPC supports many languages such as C#, Java, Python and more you check the supported languages from this link<\/a>.<\/p>\n\n\n\n We will learn the basic concepts of gRPC by doing, we will write a simple service in go to deal with user accounts as a server and use C# as a client to call and use it.<\/p>\n\n\n\n let\u2019s create a file called account.proto<\/em> At the begging, we specified that we will use proto3 which is the latest version of protocol buffers language, if we didn\u2019t specify it, it will assume that we\u2019re using proto2 and we don\u2019t want this to happen.<\/p>\n\n\n\n After that, we specified the package name which will be the package name in go or the namespace in C# later, for more information check the link<\/a>. Inside the service <\/strong>we specify the methods that we need to use in our service, we specify what input we need and what output will be produced from this method and the type of input and output is a message<\/em><\/strong>.<\/p>\n\n\n\n We have inside the service two methods one for creating an account which will take CreateAccountRequest as an input and return CreateAccountResponse. Ok, this is the definition but where I\u2019ll write my implementation? wait this will come next.<\/p>\n\n\n\n Let me explain what i have made here step by step:<\/p>\n\n\n\n 1- I imported\u00a0pb \u201cgithub.com\/Ahmad-Magdy\/grpc-by-example\/proto-go\u201d<\/em>\u00a0which contains the compiled proto file (\u201caccount.pb.go\u201d). enough talking and let\u2019s try to run the server program.<\/p>\n\n\n\n No error message, so everything is just fine \ud83c\udf89\ud83c\udf89.<\/p>\n\n\n\n let\u2019s go the client part in C# and create a new solution and project.<\/p>\n\n\n\n We made a new solution then we created a new project as base which will contain the proto packages in C# and also the generated files from the proto file in C# format.<\/p>\n\n\n\n We have to include <Protobuf> as Item group the comiler the .proto file every time we build the project.<\/p>\n\n\n\n By the end of the process we should have csproj looks like this:<\/p>\n\n\n\n If you run \u201cdotnet build\u201d you should be able to see two generated files, Account and AccountGrpc which we will use later.<\/p>\n\n\n\n Now let\u2019s create the actual client in the solutions\u2019 folder.<\/p>\n\n\n\n In this article, we learned about how to get started with gRPC, we learned about it by doing a small service in go and use it in C# which totally different language.<\/p>\n\n\n\n TODO: Share the project in Github.<\/p>\n\n\n\nDefining the service and message types by using Protobuf.<\/h2>\n\n\n\n
<\/p>\n\n\n\nsyntax = \"proto3\";\n\npackage accountproto;\n\nmessage CreateAccountRequest{\n string username = 1;\n string email = 2;\n}\n\nmessage CreateAccountResponse{\n string id = 1;\n}\n\nmessage GetAccountInformationRequest{\n string id = 1;\n}\n\nmessage GetAccountInformationResponse{\n string id = 1;\n string username = 2;\n string email = 3;\n}\n\nservice AccountService{\n rpc CreateAccount(CreateAccountRequest) returns (CreateAccountResponse){}\n rpc GetAccountInformation(GetAccountInformationRequest) returns (GetAccountInformationResponse){}\n}\n<\/code><\/pre>\n\n\n\n
The rest of the file consists of messages and service.
A message<\/strong> is what will be input or output from a service method which we define after, properties inside the message can be string, bytes, int32, float, double, and you check the rest of the supported types here<\/a>.
the number we specify after each property must be unique because it will represent the property name after the serialization process.<\/p>\n\n\n\n
The other one to get the account information which will take GetAccountInformationRequest as an input and return GetAccountInformationResponse.<\/p>\n\n\n\nHow to compile this\u00a0file:<\/h2>\n\n\n\n
protoc -I ..\/account-proto --go_out=plugins=grpc:.\/proto-go ..\/account-proto\/account.proto<\/code><\/li>
<\/li><\/ul>\n\n\n\npackage main\n\nimport (\n\t\"context\"\n\t\"fmt\"\n\t\"log\"\n\t\"net\"\n\t\"errors\"\n\n\tpb \"github.com\/Ahmad-Magdy\/grpc-by-example\/proto-go\"\n\n\t\"google.golang.org\/grpc\"\n\t\"google.golang.org\/grpc\/reflection\"\n\t\"github.com\/satori\/go.uuid\"\n)\n\ntype Account struct {\n\tID string\n\tUsername string\n\tEmail string\n}\n\nvar (\n\taccounts []*Account\n)\n\ntype server struct{}\n\nfunc (s *server) CreateAccount(ctx context.Context, accountRequest *pb.CreateAccountRequest) (*pb.CreateAccountResponse, error) {\n\tfmt.Printf(\"Server: Recived, %s\\n\", accountRequest.GetUsername())\n\n\tnewAccount := &Account{\n\t\tID: uuid.NewV4().String() ,\n\t\tUsername: accountRequest.GetUsername(),\n\t\tEmail: accountRequest.GetEmail(),\n\t}\n\n\taccounts = append(accounts, newAccount)\n\treturn &pb.CreateAccountResponse{Id: newAccount.ID}, nil\n}\n\nfunc (s *server) GetAccountInformation(ctx context.Context, m *pb.GetAccountInformationRequest) (*pb.GetAccountInformationResponse,error){\n\t for _,accountItem:= range accounts{\n\t\t if accountItem.ID == m.GetId(){\n\t\t\t return &pb.GetAccountInformationResponse{\n\t\t\t\t\t\t\t\t\t\t\tId:accountItem.ID, \n\t\t\t\t\t\t\t\t\t\t\tUsername : accountItem.Username, \n\t\t\t\t\t\t\t\t\t\t\tEmail:accountItem.Email, }, nil\n\t\t }\n\n\t }\n\t return nil, errors.New(\"account not found\")\n}\n\nfunc main() {\n\tlis, err := net.Listen(\"tcp\", \":3000\")\n\tif err != nil {\n\t\tlog.Fatal(\"Failed to listen: %v\", err)\n\t}\n\n\ts := grpc.NewServer()\n\tpb.RegisterAccountServiceServer(s, &server{})\n\treflection.Register(s)\n\tif err := s.Serve(lis); err != nil {\n\t\tlog.Fatal(\"Failed to serve: %v\", err)\n\t}\n}\n\n<\/code><\/pre>\n\n\n\n
2- I defined a new struct called\u00a0server<\/em>\u00a0which will contain the implementation of the methods we defined in the proto file.
3- We have two methods CreateAccount and GetAccountInformation so i created them.
4- I wrote a simple implementation of the two methods, it\u2019s not efficient or the best but it\u2019s enough to show you how it works.
5- Inside func main i created a new\u00a0grpc server<\/em>\u00a0and register my service in it, the code of registering the service\u00a0RegisterAccountServiceServer is autogenerated code from the compiled proto file that we defined.<\/em><\/p>\n\n\n\nTrying the\u00a0server:<\/h2>\n\n\n\n
![\"\"](\"https:\/\/magdy.dev\/blog\/wp-content\/uploads\/2019\/06\/grpc_console_go_run-1024x290.png\")
<\/figure>\n\n\n\nThe C#\u00a0part:<\/h2>\n\n\n\n
dotnet new sln --name xyz\ndotnet new classlib --name AccountServiceBase\ndotnet sln account-service-client.sln add AccountServiceBase\/AccountServiceBase.csproj\ncd AccountServiceBase\ndotnet add package Grpc\ndotnet add package Grpc.Tools\ndotnet add package Google.Protobuf\n<\/code><\/pre>\n\n\n\n<\/code><Project Sdk=\"Microsoft.NET.Sdk\">
<PropertyGroup>
<TargetFramework>netstandard2.0<\/TargetFramework>
<\/PropertyGroup>
<ItemGroup>
<PackageReference Include=\"Google.Protobuf\" Version=\"3.6.1\" \/>
<PackageReference Include=\"Grpc\" Version=\"1.18.0\" \/>
<PackageReference Include=\"Grpc.Tools\" Version=\"1.18.0\">
<IncludeAssets>runtime; build; native; contentfiles; analyzers<\/IncludeAssets>
<PrivateAssets>all<\/PrivateAssets>
<\/PackageReference>
<\/ItemGroup>
<ItemGroup>
<Protobuf Include=\"..\/..\/**\/*.proto\" OutputDir=\"%(RelativePath)\" CompileOutputs=\"false\" \/>
<\/ItemGroup>
<\/Project>
<\/pre>\n\n\n\ndotnet new console --name AccountServiceClient\ndotnet sln account-service-client.sln add AccountServiceClient\/AccountServiceClient.csproj\ndotnet add AccountServiceClient\/AccountServiceClient.csproj reference AccountServiceBase\/AccountServiceBase.csproj\n<\/code><\/pre>\n\n\n\nstatic void Main(string[] args)\n{\n var channel = new Channel(\"localhost:3000\", ChannelCredentials.Insecure);\n\n var client = new AccountService.AccountServiceClient(channel);\n\n var reply = client.CreateAccount(new CreateAccountRequest() {Username = \"Adam\",Email = \"a@amagdy.me\"});\n \n Console.WriteLine($\"Reply from the server with message {reply.Id}\");\n\n channel.ShutdownAsync().Wait();\n}\n<\/code><\/pre>\n\n\n\n![\"\"](\"https:\/\/magdy.dev\/blog\/wp-content\/uploads\/2019\/06\/grpc_running_program-1024x289.png\")
<\/figure>\n\n\n\nConclusion<\/h2>\n\n\n\n