Generate response example values using swagger with GRPC - swagger

Question

I'm generating swagger json file using protoc-gen-swagger with gRPC service. The output json is being generated with empty response examples, I want to add response examples to the definition so it gets automatically populated in the generated json.
This is my current definition.
service UserService {
rpc GetUser (GetUserRequest) returns (UserResponse){
option (google.api.http) = {
get: "/api/v1/user/{username}"
response_body: "*"
};
option (grpc.gateway.protoc_gen_swagger.options.openapiv2_operation) = {
description: "Returns user object";
operation_id: "get_user";
summary: "Get User";
};
}
}
message GetUserRequest {
string username = 1;
}
message UserResponse {
User user = 1;
}
message User {
string first_name = 1;
string last_name = 2;
string username = 3;
}
When I generate the swagger file using the command
protoc -I ${PROTOPATH} \
-I $GOPATH/src \
--swagger_out=logtostderr=true:${OUT_PATH}
I get a swagger file with this user object definition
"User": {
"type": "object",
"properties": {
"first_name": {
"type": "string"
},
"last_name": {
"type": "string"
},
"username": {
"type": "string"
},
}
}
What I want is to generate it with example values like this:
"User": {
"type": "object",
"properties": {
"first_name": {
"type": "string",
"example": "Adam"
},
"last_name": {
"type": "string",
"example": "Smith"
},
"username": {
"type": "string",
"example": "asmith79"
},
}
}

Answer 1

Found the answer to this here: https://github.com/grpc-ecosystem/grpc-gateway/blob/master/examples/internal/proto/examplepb/a_bit_of_everything.proto#L197
Simple by adding grpc.gateway.protoc_gen_swagger.options.openapiv2_schema as an option to the message.
import "protoc-gen-swagger/options/annotations.proto";
message User {
option (grpc.gateway.protoc_gen_swagger.options.openapiv2_schema) = {
example: { value: '{ "first_name": "Adam", "last_name":"Smith", "username":"asmith79"}' }
};
string first_name = 1;
string last_name = 2;
string username = 3;
}