RPC (Remote Procedure Call)

Make calling code on a remote machine feel like calling it local.

RPC handles everything (boilerplate) underneath.

(otherwise http JSON → call → parse response → handle errors)

rpc

Notes

  • stubs are auto generated code that performs plumbing code itself.

gRPC are faster than REST & graphQL

Why

Protocol Buff (binary encoding)

  • JSON → binary
  • 1KB → 200 bytes

HTTP/2

  • rest runs on HTTP/1.1 (each req needs new connection)
  • HTTP/2 supports streaming in both direction

Protobufs (Protocol Buffers)

  • google invented
  • serialize to binary

Steps

  1. we just write a "proto" file that describe data structure/format
  2. tools auto generate code in any language

.proto file

message User {
  int32 id = 1;
  string name = 2;
}

1,2 are sent (in binary) not "name", "id" etc.

service UserService {
  rpc GetUser (UserRequest) returns (User);
  rpc ListUsers (Empty) returns (stream User)->streaming;
}

Where it is used

  • microservices (high internal calls)
  • mobile clients (low battery, low network used)
  • real-time streaming
  • multi language systems