Create a REST service using Go Language and BeeGo Framework.

Oleh Web-git 05 Agu, 2018 Posting Komentar

Golang
Go is an Open Source programming language developed by Google Inc.
To install go latest:

wget https://storage.googleapis.com/golang/go1.9.1.linux-amd64.tar.gz
Unzip in /usr/local directory:

sudo tar -C /usr/local -xzf go1.9.1.linux-amd64.tar.gz
tar -C ./ -xzf go1.9.1.linux-amd64.tar.gz
Then, modify /etc/profile file, add this line:

export PATH=$PATH:/usr/local/go/bin
also, add these lines in /home/$USER/.profile file:

export GOPATH=$HOME/golangProjects
export GOROOT=$HOME/go
export PATH=$PATH:$GOROOT/bin
Installing some libraries or dependencies for Golang
Web Frameworks

BeeGo

BeeGo is a Web Framework to develop using Golang Web Applications or RESTful services, you can find more information pressing here.
You can install on local writting this on terminal:

go get github.com/astaxie/beego
go get github.com/beego/bee
Then, move the golangProjects/bin/bee binary to go/bin directory.

REST Service

REST(REpresentational State Transfer) is an architecture that use HTTP protocol which provide an API with methods like GET, POST, PUT, DELETE, etc.
We use BeeGo framework and mgo driver to create a REST service on Golang using MongoDB:

First, once installed go and beego framework binaries, creates a directory and write in shell:
```
bee api myapi
```
The tree directory is like:
Second, you should download the database drivers, in my case is MongoDB.

DataBases Drivers

mgo

Is the MongoDB Driver for Golang. For more information or Doc press here.
To install, write on terminal:

go get gopkg.in/mgo.v2
go get gopkg.in/check.v1

Third, install mongoDB, you can see my example pressing here or see official doc here.

I use a Singleton Pattern to connect to database, like this:

    type singletonMongoDBSession struct {
      session *mgo.Session
      errDial error
    }

    var instance *singletonMongoDBSession
    var once sync.Once

    func GetSessErrMongoDBSession(dialInfo string) (*mgo.Session, error){
      var instance *singletonMongoDBSession
      if dialInfo == "Dial"{
        instance = NewMongoDBSession()
      } else if dialInfo == "DialWithInfo"{
        instance = NewMongoDBSessionInfo()
      }
      return instance.session, instance.errDial
    }
      
    func NewMongoDBSession() (*singletonMongoDBSession) {
      once.Do(func() {
        sess, err := mgo.Dial(urldb)
        instance = &singletonMongoDBSession{session: sess, errDial: err}
      })
      return instance
    }

Then, my model is like:

    type Login struct{
      Username           string       `json:"username"`
      Password           string       `json:"password"`
    }

    var login Login

    func init(){}

    func VerifyLogin(object Login) (ObjectId bool, err error) {
      objlogin := loginRequest(object)
        if objlogin == (Login{}) {
        fmt.Printf("\nNo se encontro Usuario !\n\n")
        return false, nil
      } else {
        return true, nil
      }
    }

I modify some files and add directories to make more understandable how you can separates service or information.

You can see my restapi-BeeGo example, just pressing there :D .

Another Packages for develop in Golang

Communitacion Protocols

MQTT Paho Golang

Is the MQTT library for Golang. For more information press here.
To install, write on terminal:

go get github.com/eclipse/paho.mqtt.golang

To configure Mosquitto service, you can check my tuto pressing here.

Mail Service

GoMail

Is the SMTP library for Golang. For more information press here.
To install, write on terminal:

go get gopkg.in/gomail.v2
Source : https://jenazad.github.io/frameworks/Create-a-REST-service-using-Go-Language-and-BeeGo-Framework

IDwebgit