auth()->attempt($credentials)到底是什么？

if (! $token = auth()->attempt($credentials)) {
return response()->json([‘error’ => ‘账号或密码错误’], 401);
}

这部分是 laravel guard 的知识

我们在 config/auth 中设置了不同的 guard

'guards' => [
    'web' => [
        'driver' => 'session',
        'provider' => 'users',
    ],

    'api' => [
        'driver' => 'jwt',
        'provider' => 'users',
    ],
],

\Auth::guard (‘api’) 意思是使用 api guard，根据配置使用的 driver 是 jwt，provider 是 users。

driver jwt 在 jwt-auth 这个扩展中定义了

vendor/tymon/jwt-auth/src/Providers/AbstractServiceProvider.php

.
.
.
    protected function extendAuthGuard()
    {
        $this->app['auth']->extend('jwt', function ($app, $name, array $config) {
            $guard = new JwtGuard(
                $app['tymon.jwt'],
                $app['auth']->createUserProvider($config['provider']),
                $app['request']
            );

            $app->refresh('request', $guard, 'setRequest');

            return $guard;
        });
    }
.
.
.

你会看到最终是执行的 vendor/tymon/jwt-auth/src/JwtGuard.php 中的 attempt 方法

    public function attempt(array $credentials = [], $login = true)
    {
        $this->lastAttempted = $user = $this->provider->retrieveByCredentials($credentials);

        if ($this->hasValidCredentials($user, $credentials)) {
            return $login ? $this->login($user) : true;
        }

        return false;
    }