1 Iris 8.3.0 Released with first-class support for the MVC architecture pattern

github.com godoc.org goreportcard.com posted by iris-go 2688 days ago  

MVC (Model View Controller)

From version 8.3 and after Iris has first-class support for the MVC pattern, you'll not find these stuff anywhere else in the Go world.

Example Code

package main

import (
	"sync"

	"github.com/kataras/iris"
	"github.com/kataras/iris/mvc"
)

func main() {
	app := iris.New()
	app.RegisterView(iris.HTML("./views", ".html"))

	// when we have a path separated by spaces
	// then the Controller is registered to all of them one by one.
	//
	// myDB is binded to the controller's `*DB` field: use only structs and pointers.
	app.Controller("/profile /profile/browse /profile/{id:int} /profile/me",
		new(ProfileController), myDB) // IMPORTANT

	app.Run(iris.Addr(":8080"))
}

// UserModel our example model which will render on the template.
type UserModel struct {
	ID       int64
	Username string
}

// DB is our example database.
type DB struct {
	usersTable map[int64]UserModel
	mu         sync.RWMutex
}

// GetUserByID imaginary database lookup based on user id.
func (db *DB) GetUserByID(id int64) (u UserModel, found bool) {
	db.mu.RLock()
	u, found = db.usersTable[id]
	db.mu.RUnlock()
	return
}

var myDB = &DB{
	usersTable: map[int64]UserModel{
		1:  {1, "kataras"},
		2:  {2, "makis"},
		42: {42, "jdoe"},
	},
}

// ProfileController our example user controller which controls
// the paths of "/profile" "/profile/{id:int}" and "/profile/me".
type ProfileController struct {
	mvc.Controller // IMPORTANT

	User UserModel `iris:"model"`
	// we will bind it but you can also tag it with`iris:"persistence"`
	// and init the controller with manual &PorifleController{DB: myDB}.
	DB *DB
}

// Get method handles all "GET" HTTP Method requests of the controller's paths.
func (pc *ProfileController) Get() { // IMPORTANT
	path := pc.Path

	// requested: /profile path
	if path == "/profile" {
		pc.Tmpl = "profile/index.html"
		return
	}
	// requested: /profile/browse
	// this exists only to proof the concept of changing the path:
	// it will result to a redirection.
	if path == "/profile/browse" {
		pc.Path = "/profile"
		return
	}

	// requested: /profile/me path
	if path == "/profile/me" {
		pc.Tmpl = "profile/me.html"
		return
	}

	// requested: /profile/$ID
	id, _ := pc.Params.GetInt64("id")

	user, found := pc.DB.GetUserByID(id)
	if !found {
		pc.Status = iris.StatusNotFound
		pc.Tmpl = "profile/notfound.html"
		pc.Data["ID"] = id
		return
	}

	pc.Tmpl = "profile/profile.html"
	pc.User = user
}


/*
func (pc *ProfileController) Post() {}
func (pc *ProfileController) Put() {}
func (pc *ProfileController) Delete() {}
func (pc *ProfileController) Connect() {}
func (pc *ProfileController) Head() {}
func (pc *ProfileController) Patch() {}
func (pc *ProfileController) Options() {}
func (pc *ProfileController) Trace() {}
*/

/*
func (pc *ProfileController) All() {}
//        OR
func (pc *ProfileController) Any() {}
*/

Iris web framework supports Request data, Models, Persistence Data and Binding with the fastest possible execution.

Characteristics

All HTTP Methods are supported, for example if want to serve GET then the controller should have a function named Get(), you can define more than one method function to serve in the same Controller struct.

Persistence data inside your Controller struct (share data between requests) via iris:"persistence" tag right to the field or Bind using app.Controller("/" , new(myController), theBindValue).

Models inside your Controller struct (set-ed at the Method function and rendered by the View) via iris:"model" tag right to the field, i.e User UserModel `iris:"model" name:"user"` view will recognise it as {{.user}}. If name tag is missing then it takes the field's name, in this case the "User".

Access to the request path and its parameters via the Path and Params fields.

Access to the template file that should be rendered via the Tmpl field.

Access to the template data that should be rendered inside the template file via Data field.

Access to the template layout via the Layout field.

Access to the low-level context.Context via the Ctx field.

Flow as you used to, Controllers can be registered to any Party, including Subdomains, the Party's begin and done handlers work as expected.

Optional BeginRequest(ctx) function to perform any initialization before the method execution, useful to call middlewares or when many methods use the same collection of data.

Optional EndRequest(ctx) function to perform any finalization after any method executed.

Inheritance, see for example our mvc.SessionController, it has the mvc.Controller as an embedded field and it adds its logic to its BeginRequest, here.

Using Iris MVC for code reuse

By creating components that are independent of one another, developers are able to reuse components quickly and easily in other applications. The same (or similar) view for one application can be refactored for another application with different data because the view is simply handling how the data is being displayed to the user.

If you're new to back-end web development read about the MVC architectural pattern first, a good start is that wikipedia article.

Follow the examples below,

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