Microservices Engine:Route requests of gRPC applications based on cloud-native gateways

Step 1: Deploy a gRPC application in the ACK cluster

For more information about how to deploy an application, see Create a stateless application by using a Deployment.

apiVersion: apps/v1
kind: Deployment
metadata:
  name: grpcbin
spec:
  replicas: 1
  selector:
    matchLabels:
      app: grpcbin
  template:
    metadata:
      labels:
        app: grpcbin
    spec:
      serviceAccountName: grpcbin
      containers:
      - image: docker.io/moul/grpcbin
        imagePullPolicy: IfNotPresent
        name: grpcbin
        ports:
        - containerPort: 9000
        - containerPort: 9001
        resources:
            requests:
              cpu: '1'
              memory: 2Gi
            limit:
              cpu: '1'
              memory: 2Gi
---
apiVersion: v1
kind: ServiceAccount
metadata:
  name: grpcbin
---
apiVersion: v1
kind: Service
metadata:
  name: grpcbin-grpc
  labels:
    app: grpcbin
spec:
  ports:
  - name: grpc
    port: 9000
    targetPort: 9000
  selector:
    app: grpcbin

The following code shows the proto definition for the gRPC service.

syntax = "proto3";

package grpcbin;

service GRPCBin {
  rpc Index(EmptyMessage) returns (IndexReply) {}
  // The method that is called without parameters specified. An empty response is returned after the call.
  rpc Empty(EmptyMessage) returns (EmptyMessage) {}
  // The request parameters are returned.
  rpc DummyUnary(DummyMessage) returns (DummyMessage) {}
  // A streaming call is initiated for the response, and 10 response messages are returned.
  rpc DummyServerStream(DummyMessage) returns (stream DummyMessage) {}
  // A streaming call is initiated for the request, 10 requests are received, and the last request body is returned.
  rpc DummyClientStream(stream DummyMessage) returns (DummyMessage) {}
  // The streaming method that is used for both requests and responses.
  rpc DummyBidirectionalStreamStream(stream DummyMessage) returns (stream DummyMessage) {}
  // After this method is called, a specified gRPC error is returned.
  rpc SpecificError(SpecificErrorRequest) returns (EmptyMessage) {}
  // After this method is called, a random error is returned.
  rpc RandomError(EmptyMessage) returns (EmptyMessage) {}
  // After this method is called, a header is returned.
  rpc HeadersUnary(EmptyMessage) returns (HeadersMessage) {}
  // After this method is called, no response is returned.
  rpc NoResponseUnary(EmptyMessage) returns (EmptyMessage) {}
}

message HeadersMessage {
  message Values {
    repeated string values = 1;
  }
  map<string, Values> Metadata = 1;
}

message SpecificErrorRequest {
  uint32 code = 1;
  string reason = 2;
}

message EmptyMessage {}

message DummyMessage {
  message Sub {
    string f_string = 1;
  }
  enum Enum {
    ENUM_0 = 0;
    ENUM_1 = 1;
    ENUM_2 = 2;
  }
  string f_string = 1;
  repeated string f_strings = 2;
  int32 f_int32 = 3;
  repeated int32 f_int32s = 4;
  Enum f_enum = 5;
  repeated Enum f_enums = 6;
  Sub f_sub = 7;
  repeated Sub f_subs = 8;
  bool f_bool = 9;
  repeated bool f_bools = 10;
  int64 f_int64 = 11;
  repeated int64 f_int64s= 12;
  bytes f_bytes = 13;
  repeated bytes f_bytess = 14;
  float f_float = 15;
  repeated float f_floats = 16;
}

message IndexReply {
  message Endpoint {
    string path = 1;
    string description = 2;
  }
  string description = 1;
  repeated Endpoint endpoints = 2;
}

The underlying layer of the gRPC service is based on the HTTP/2 protocol, and the Path field is in the format of {Package name}.{Service name}/{Method name}. MSE cloud-native gateways can use the Path field to implement gRPC routing. For example, if you use gRPC to access the Index method of grpcbin, the value of the Path field for the HTTP/2 protocol is grpcbin.GRPCBin/Index.

Step 2: Use the cloud-native gateway to route gRPC requests

Add the ACK cluster as a service source of the cloud-native gateway and add the grpcbin service.

Verify the result

Use BloomRPC to test the gRPC service availability. If a response is returned, the gRPC service is available.