Modern webservices using gRPC and Protocol Buffers in Golang

Creating modern webservices
in
Golang
// Omid Hojabri
// E-mail: o.hojabri@gmail.com
// Skype: hojabri
// LinkedIn: linkedin.com/in/hojabri
using gRPC + Protocol
Buffers

REST : Popular API
 REST (HTTP-JSON)
 JSON
 Format in URL:
 GET /api/v1/user/231/roles/453
 POST /api/v1/user/231/roles
 PUT …
 DELETE ...

Concerns about APIs
 Data size
 Latency
 Scalability
 Load Balancing
 Communication between languages
 Authentication
 Monitoring
 Logging

What is an API
 Is a contract
 Client sends REQUEST
 Server sends RESPONSE

gRPC
 Is a free and open-source framework developed by
 Allows to simply define REQUEST and RESPONSE for RPC (Remote Procedure Calls)
 Modern, Fast, Efficient (based on HTTP/2)
 Low latency
 Supports streaming
 Many languages support it
 Authentication, Monitoring, Load balancing and Logging are easy to define with gRPC
 Many companies like Google, Netflix, Square, CoreOS, Spotify, Docker, Cisco,… using it fully.

Official supported languages
 C/C++
 Java
 Android Java
 Go
 C#
 Kotlin
 Node.js
 Objective-C
 PHP (Beta)
 Python
 Ruby
 Dart

RPC
 Remote Procedure Call
 Client calls functions directly on the server
 gRPC implements RPC very cleanly and it solves a
lot of problems

gRPC overview
gRPC uses protocol buffers (protobuf) to communicate between clients and servers

How it runs?
 gRPC needs to define messages and services using Protocol
Buffers
 gRPC codes will be generated automatically with “protoc”
command!
 Data is binary
 You need just implementing the methods defined based on your
message type
 Defining Protocol Buffers in .proto files.

.proto files
 We define
messages and
service
definitions in
.proto files.
 (API contract)

Types of API in gRPC
1 Unary
2 Server Streaming
3 Client Streaming
4 Bi-directional Streaming

Unary API
Client Server
Request
Response

Server Streaming API
Client Server
Request
Message 1
Message 2
Message 3
Message n
.
.
.
.

Client Streaming API
Client Server
Message 1
Message 2
Message 3
Message n
Response
.
.
.
.

Bi-directional Streaming API
Client Server
Client Message 1
Client Message 2
Client Message 3
Server Message 3
Server Message 4
Server Message n
Client Message 4
Client Message n
Server Message 2
Server Message 1

gRPC vs REST
gRPC REST
Data is binary, smaller and communication is faster (25
more performance based on benchmarks)
Text based, bigger and slower
HTTP/2 (Low latency) HTTP/1.1 (Higher latency)
Unary, Server streaming, Client streaming, bi-
directional streaming
Request – Response only
Any API commands CRUD (Create – Retrieve – Update – Delete) POST –
GET – PUT - DELETE
Code generation by protocol buffers in any language Manual code or by OpenAPI/Swagger
RPC based HTTP words based

Installation
 Prerequisites:
 Go to be installed (any one of the three latest major
release)
 Protocol Buffer compiler (protoc v3)
 Go plugin for protocol compiler

Protocol Buffer Compiler (v3)
 The protocol buffer compiler (protoc) is used to
compile (code generation) .proto files, which contain
service and message definitions.
 Linux:

 MacOS:


Protocol Buffer Compiler (v3)
 Windows:
 Download and install the latest release of binary version
from:
 https://github.com/protocolbuffers/protobuf/releases/tag/v3.13.0
 (at the moment v3.13.0 is released)

Go plugin for the protocol
buffers
1 Install the protocol compiler plugin for Go (protoc-gen-go)
using the following command:
2 Update your PATH so that the protoc compiler can find the
plugin:

Installing dependencies
 Installing go grpc module: https://github.com/grpc/grpc-
go
 (It may take some time to install completely)

Configuration of a .proto file
 Syntax version and package definition:

 Message definition:

 Service Definition:

Generating Code
 Will generate a file called “greet.pb.go”

Full sample source code
 I’ve uploaded my sample source code which covers
all four types of gRPC API
https://github.com/hojabri/grpc-pr

Thank you
Github: https://github.com/hojabri
E-mail: o.hojabri@gmail.com
Skype: hojabri
LinkedIn: https://linkedin.com/in/hojabri

Modern webservices using gRPC and Protocol Buffers in Golang

More Related Content

What's hot (20)

Similar to Modern webservices using gRPC and Protocol Buffers in Golang (20)

Recently uploaded (20)

Modern webservices using gRPC and Protocol Buffers in Golang