@42withyou 2016-09-23T07:25:18.000000Z 字数 8221 阅读 596

容器，依赖注入，控制反转

未分类

public function __construct()
{
    $this->users = new UserRepository;
}
public function __construct(UserRepository $users)
{
    $this->users = $users;
}

注册一个实例到容器中

$this->app['context'] = $this->app->share(function ($app) {
    return new Context;
});

或者绑定一个 Interface 到一个实体(Entity)

$this->app->bind(
    \App\Repositories\Api\UserRepositoryInterface::class,
    \App\Repositories\Api\Eloquent\UserRepository::class
);

参考灵析 api

不过类似 context 这种需求，在整个应用生命周期只需要一个，所以

$this->app->singleton('context', function () {
    return $this->app->make(\App\Utilities\Context\Context::class);
});

关于 Conainer 的实现, 有 laravel 的实现方式 Illuminate\Container，基本上出了 Thinkphp 所有国外框架都有容器这么一个概念。

参考 Demo

Facade

<?php
use Context;
class HomeController
{
    public function index()
    {
        Context::all();
    }
}

<?php
class ContextFacade extends Facade
{
    protected static function getFacadeAccessor()
    {
        return 'context';
    }
}

<?php
abstract class Facade
{
    protected static function getFacadeAccessor()
    {
        throw new RuntimeException('Facade does not implement getFacadeAccessor method.');
    }
    public static function __callStatic($method, $args)
    {
        // 返回容器中绑定的对象
        $instance = static::getFacadeRoot();
        if (! $instance) {
            throw new RuntimeException('A facade root has not been set.');
        }
        // ...$args ???
        return $instance->$method(...$args);
    }
}

关于解构符(spread operator)

function foo($a, ...$args)
{
    $a // 1,
    $args // [2,3,4]
}
foo(...[1,2,3,4]);

Collection

先看个例子感受一波

return collect($users)
    ->filter(function ($user) {
         return $user->isActive();
    })
    // ->reject(function ($user) { return $user->notActive() })
    ->map(function ($user) {
        return $user->posts;
    })
    ->reduce(function ($total, $item) {
        return $total + $item->commentCount;    
    }, 0);
    // ->sum('commentCount');

获取所有单身狗的邮箱

$people = collect([
    ['name' => 'RryLee', 'single' => true, 'email' => 'RryLee@justering.com'],
    ['name' => 'Yekz', 'single' => true, 'email' => 'Yekz@justering.com'],
    ['name' => 'Ferman', 'single' => false, 'email' => 'Ferman@justering.com'],
    ['name' => 'Sky', 'single' => true, 'email' => 'Sky@justering.com'],
    ['name' => 'Casper', 'single' => false, 'email' => 'Casper@justering.com'],
]);
$emails = [];
foreach ($people as $person) {
    if ($person['single']) {
        $emails[] = $person['email'];
    }
}
// collection.
$people->filter(function ($person) {
    return $person->single;
})->pluck('email');

获取代码行数最多的项目名称

$people = collect([
    [
        'name' => 'RryLee',
        'email' => 'RryLee@justering.com',
        'projects' => [
            ['name' => 'api', 'code_line' => 7444],
            ['name' => 'cfnew', 'code_line' => 5020],
            ['name' => 'lingxi', 'code_line' => 1200],
        ],
    ],
    [
        'name' => 'Yekz',
        'email' => 'Yekz@justering.com',
        'projects' => [
            ['name' => 'api', 'code_line' => 120],
            ['name' => 'cfnew', 'code_line' => 4000],
            ['name' => 'lingxi', 'code_line' => 8000],
            ['name' => 'mail', 'code_line' => 2122],
            ['name' => 'pay', 'code_line' => 1201],
        ],
    ],
    [
        'name' => 'Ferman',
        'email' => 'Ferman@justering.com',
        'projects' => [
            ['name' => 'cfnew', 'code_line' => 3000],
            ['name' => 'lingxi', 'code_line' => 5000],
            ['name' => 'pay', 'code_line' => 7000],
        ],
    ],
]);
$people->pluck('projects')
    /**
     * [
     *     [
                ['name' => 'api', 'code_line' => 7444],
                ['name' => 'cfnew', 'code_line' => 5020],
                ['name' => 'lingxi', 'code_line' => 1200],
     *     ],
     *     [...],
     *     [...],
     * ]
     */
    ->flatten(1)
    /**
     * [
     *     ['name' => 'api', 'code_line' => 7444],
     *     ['name' => ...],
     *     ['name' => ...],
     * ]
     */
    ->groupBy('name')
    /**
     * [
     *     'api' => [
     *         ['name' => 'api', 'code_line' => 7444],
     *         ['name' => 'api', 'code_line' => ...],
     *         ['name' => 'api', 'code_line' => ...],
     *     ],
     *     'cfnew' => [
     *         ...
     *     ]
     * ]
     */
    ->map(function ($groupedProjects) {
        return $groupedProjects->sum('code_line');
    })
    ->sort()
    ->reverse()
    ->keys()
    ->first();

经验，要么不用，用了就用到底，不要因为纠结用不用浪费太多时间，一般这种情况，你都写不出来，最后使用 foreach 解决了。

关于 collection 的一切，都可以在这本书里找到，Never write loop again

Eloquent 在手，天下我有

应该是 php 世界里最好用的 orm，作者也说过整个框架最难写的地方就是 eloquent 了.

参考 app.php

OneToOne || OneToMany

<?php
namespace App;
use Eloquent;
class Post extends Eloquent
{
    public function comments()
    {
        return $this->hasMany(Comment::class);
    }
}

public function show($id)
{
    $post = Post::with('comments')->findOrFail($id); // 普通关联查询
    $post = Post::withCount('comments')->findOrFail($id); // 带上 count
    $post = Post::with([
        'comments' => function ($q) {
            return $q->latest('create_time');
        }
    ])->findOrFail($id);
}

public function recentComments()
{
    return $this->hasMany(Comment::class)
        ->where('created_at', '>', Carbon::yesterday());
}

public function scopeSince($query, $since, $column = 'created_at')
{
    return $query->where($column, '>', $since);
}
public function scopeSinceYesterday($query)
{
    return $this->since(Carbon::yesterday());
}
public function recentComments()
{
    return $this->hasMany(Comment::class)->sinceYesterday();
}

save comment?

public function store(Request $request, Post $post)
{
    // not to do like this!
    Comment::create([
        'post_id' => $post->id,
        'content' => 'wow!'
    ]);
    // here
    $post->comments()->create([
        'content' => 'wow!'
    ]);
}

class Post
{
    public function newComment($attributes)
    {
        return $this->comments()->create($attributes);
    }
}

只有这样的写法才能叫 Eloquent.

BelongsTo || BelongsToMany

class Post
{
    public function author()
    {
        return $this->belongsTo(Author::class);
    }
}

class Post
{
    public function newComment($author, $attributes)
    {
        $comment = new Comment($attributes);
        $comment->author()->associate($author);
        return $this->comments()->save($comment);
    }
}

关于 eloquent 和 repository 的选择

这一直都是一个社区争论很多的话题

直接使用 eloquent

方便
直接
优雅

同时

Model 太重
和 Controller 严重耦合

添加 repository 层后

Model 层几乎没有做太多事情
Controller 也干净了很多

导致

文件目录的增加是必然的
有很多时候你都想去直接使用 model，一些非常简单的 CURD
某些场景(api，需要url的很多参数)会和 request 在 repository 中严重耦合。(如果是 eloquent，那么只需要在 controller 中去使用 request 就好，不会影响整个应用层的体系结构)

整个应用生命周期

Eloquent

Millleware->Request->Controller->Eloquent->Response

Repository

Millleware->Request->Controller->Repository(Eloquent + Resquest)->Response

Eloquent 进阶

请食用 https://github.com/LingxiTeam/learn-eloquent 来进行深入实战学习。
目前内容并不太多，有时间都会抽空出来补充。

测试

Not jus TDD(Test-driven development), we want BDD(Behavior-driven development)

行为测试

class ExampleTestextendsTestCase
{
    /**
     * A basic functional test example.
     * @return void
     */
    public function testBasicExample()
    {
        $this->visit('/')
             ->see('Laravel 5')
             ->dontSee('Rails');
     }
 }

JSON API TEST

public function testSaveComment()
{
    $comment = str_random(16);
    $this->post('/api/v1/comment', ['content' => $comment])
         ->seeJson([
            'status_code' => '201',
            'message' => 'Created.'
         ])
         ->seeInDatabase('comments', ['content' => $comment]);
}

好的测试应该从 0 开始 (仅代表个人观点)

写好测试数据来源

$factory->define(App\Models\Team\Contact::class, function (Faker\Generator $faker) {
    $birthday = $faker->date();
    return [
        'old_id' => mt_rand(100000, 999999),
        'team_id' => 1024,
        'name' => $faker->name,
        'nickname' => $faker->username,
        'email' => $faker->email,
        'birthday' => $birthday,
        'birth' => substr($birthday, -5),
        'source' => 'create'
    ];
});

ES6

Laravel 把 Vue 推向了世界，Vue 依赖于 ES6，加上 ES7 已经开始渐渐流行，你还不会 ES6?

所以， learn es6 by php.

var, let, const

在 es6 出来之前，javascript 是没有块级作用域这个概念的

function goTop(currentHeight)
{
    if (currentHeight > 100) {
        // go...
        var gone = true;
        console.log(gone);
    } else {
        console.log(gone);
    }
}
goTop(true); // true
goTop(); // undefined, 对于 js 初学者，这里就很迷惑，Uncaught ReferenceError: gone is not defined
function goTop(currentHeight)
{
    var gone;
    if (currentHeight > 100) {
        // go...
        gone = true;
        console.log(gone);
    } else {
        console.log(gone);
    }
}
// in es6
function goTop(currentHeight)
{
    if (currentHeight > 100) {
        // go...
        let gone = true;
        console.log(gone);
    } else {
        console.log(gone);
    }
}
goTop(); Uncaught ReferenceError: gone is not defined

至于 const，也是一个块级作用域的声明，其他和 php 一样，不过在 es6 里，并不会大写

const LANGUAGE = 'PHP';
const language = 'javascript';

这里有个小坑

const DATA = [1,2,3];
DATA[] = 4; // PHP Fatal error:  Cannot use [] for reading

const data = [1,2,3];
data.push(4); // [1,2,3,4]

Object.freeze

Arrow function

投票显示 es6 中最需要的功能

var es5 = {
    go: function (a) {
        console.log(this)
    }
}
var es6 = {
    go: a => {
        console.log(this)
    }
}
// 区别在于箭头函数不会改变当前作用域，也就是 this.
es6.go() // Window {speechSynthesis: ...}...
es5.go() // Object {}
es5.go.bind(this)() // Window {speechSynthesis: ...}...

默认参数

function foo (a = 1) {
    console.log(a);
}

解构

和 php 一样，很多语言都引入了这个特性, es6 更强大就是了

function go (a, ...rest) {
    console.log(a, rest);
}
go (1,...[2,3,4]); // 1 [2, 3, 4]
let obj = {
    a: 1,
    b: 2,
    c: 3
}
var a = obj.a;
let {a, b, c} = obj;
let {a, c} = obj;
let {d} = obj; // undefined

Templete (模板字符串)

const name = 'RryLee';
console.log(`Hi!, i am ${name}`);
// echo "Hi!, i am {$name}";

模板字符串还可以添加方法，可以自行了解

class

class People {
    construct (age, name) {
        this.age = age;
        this.name = name;
    }
    say () {
        console.log(`I am ${name} and ${age} years old.`)
    }
}

class People 
{
    public function __construct (age, name) {
        $this->age = $age;
        $this->name = $name;
    }
    public function say() {
        echo 'I am ', name, ' and ', age, ' years old.'
    }
}

模块化

// util.js
export function sum(a, b) {
    return a + b;
}
// client.js
import { sum } from './util.js'
console.log(sum(1, 3)) // 4
// util.js
export default function {
    console.log('I am default function.')
}
// client.js
import say from './util'
say() // I am default function.
// more
export default {}
export const app_name = 'lingxi'
export class User {}
export ...

以上基本涵盖了 es6 的全部基础用法，关于更好玩的 (Promise, Generator...)，当然是要自己去用了。Oh, 基础的还有 for-of(用于遍历数组，以及 es6 的数据解构, set, map 等1) 和 for-in (便利对象)

一个简单的迭代器实现 php 的 range() 方法

function* range(start, end) {
    for (let i = start, j = 0; i <= end; i ++, j ++) {
        yield [i, j];
    }
}
for (let [num, i] of range(1, 10)) {
    console.log(`${i} => ${num}`);
}