Introduction to custom dependency injection examples of lumen in php

For example, I now have a token authentication system. Currently, I use mysql token table to implement it. It may be changed to redis in the future. How can I achieve seamless connections in the future?

First define a contract file app/Contracts/TokenHandler.php

<?php

namespace App\Contracts;

/**
 * 处理Token的Contracts
 * @package App\Contracts
 */
interface TokenHandler
{
    /**
     * 创建一个token
     * @param $userId integer 用户Id
     * @return string
     */
    public function createToken($userId);

    /**
     * 得到该token的用户
     * @param $token string token值
     * @return \App\User 拥有该token的用户
     */
    public function getTokenUser($token);

    /**
     * 删除一个token
     * @param $token string token值
     * @return bool 是否成功
     */
    public function removeToken($token);
}

Three methods are defined here: create token, get the user corresponding to the token, and delete token.

Then we write an implementation app/Services/MysqlTokenHandler.php under Mysql

<?php

namespace App\Services;

use App\Contracts\TokenHandler;
use App\Orm\Token;

/**
 * 处理Token的Contracts对应的Mysql Service
 * @package App\Services
 */
class MysqlTokenHandler implements TokenHandler
{
    /**
     * @var int 一个用户能够拥有的token最大值
     */
    protected $userTokensMax = 10;

    /**
     * @inheritdoc
     */
    public function createToken($userId)
    {
        while (Token::where(&#39;user_id&#39;, $userId)->count() >= $this->userTokensMax) {
            Token::where(&#39;user_id&#39;, $userId)->orderBy(&#39;updated_at&#39;, &#39;asc&#39;)->first()->delete();
        }

        $token = \Illuminate\Support\Str::random(32);
        if (!Token::create([&#39;token&#39; => $token, &#39;user_id&#39; => $userId])) {
            return false;
        }

        return $token;
    }

    /**
     * @inheritdoc
     */
    public function getTokenUser($token)
    {
        $tokenObject = Token::where(&#39;token&#39;, $token)->first();

        return $tokenObject && $tokenObject->user ? $tokenObject->user : false;
    }

    /**
     * @inheritdoc
     */
    public function removeToken($token)
    {
        return Token::find($token)->delete();
    }
}

Then Bind the mapping relationship between the two in bootstrap/app.php:

##

$app->singleton(
    App\Contracts\TokenHandler::class,
    App\Services\MysqlTokenHandler::class);

If it is replaced by redis in the future, Just rewrite an implementation of RedisTokenHandler and rebind it, and the specific business logic code does not need to be changed.

So you can directly inject the object instance in the controller, as long as you declare the contract type before the parameters:

    public function logout(Request $request, TokenHandler $tokenHandler)
    {
        if ($tokenHandler->removeToken($request->input('api_token'))) {
            return $this->success([]);
        } else {
            return $this->error(Lang::get('messages.logout_fail'));
        }
    }

You can also get the injection manually in the code An instance of an object, such as:

$currentUser = app(\App\Contracts\TokenHandler::class)->getTokenUser($request->input('api_token'));

The above is the detailed content of Introduction to custom dependency injection examples of lumen in php. For more information, please follow other related articles on the PHP Chinese website!