生成Golang grpc +自定义原型对象

I am trying to generate a gRPC client that returns a self defined proto object. This is my current proto command

protoc -I.:../ --go_out=plugins=grpc:Muser/messages.proto=github.com/.../.../user:. messages.proto

and this is the error Muser/messages.proto=github.com/.../.../user:./: No such file or directory

However this command:

protoc -I.:../ --go_out=Muser/messages.proto=github.com/.../.../user:. messages.proto

and this one:

protoc -I.:../ --go_out=plugins=grpc:. messages.proto

work perfectly. The problem is when I try to use the plugins:grpc part in conjunction to the path of the user/messages.proto file.

Any clue what the problem might be?

Per the protoc documentation here: https://github.com/golang/protobuf#parameters

To pass extra parameters to the plugin, use a comma-separated parameter list separated from the output directory by a colon:

So I believe the right command would be: protoc -I.:../ --go_out=plugins=grpc,Muser/messages.proto=github.com/.../.../user:. messages.proto