laravel踩坑記:空字符轉(zhuǎn)null

場(chǎng)景：手頭的項(xiàng)目需要對(duì)外提供API服務(wù)，需要對(duì)請(qǐng)求數(shù)據(jù)進(jìn)行簽名校驗(yàn)。提交接口的數(shù)據(jù)會(huì)有''空字符值存在，laravel的Illuminate\Foundation\Http\Request接收到參數(shù)后，會(huì)將空字符強(qiáng)制轉(zhuǎn)換為NULL,導(dǎo)致簽名校驗(yàn)通不過(guò)。

經(jīng)過(guò)一番努力，找到幕后黑手。
Illuminate/Foundation/Http組件中有定義這個(gè)中間件。
vendor/laravel/framework/src/Illuminate/Foundation/Http/Middleware/ConvertEmptyStringsToNull.php

<?php

namespace Illuminate\Foundation\Http\Middleware;

class ConvertEmptyStringsToNull extends TransformsRequest
{
    /**
     * Transform the given value.
     *
     * @param  string  $key
     * @param  mixed  $value
     * @return mixed
     */
    protected function transform($key, $value)
    {
        return is_string($value) && $value === '' ? null : $value;
    }
}

解決方法：
既然是中間件作祟，肯定在內(nèi)核中有注冊(cè)。找到內(nèi)核注釋該中間件就好。
app/Http/Kernel.php

class Kernel extends HttpKernel
{
    /**
     * The application's global HTTP middleware stack.
     *
     * These middleware are run during every request to your application.
     *
     * @var array
     */
    protected $middleware = [
        \App\Http\Middleware\CheckForMaintenanceMode::class,
        \Illuminate\Foundation\Http\Middleware\ValidatePostSize::class,
        \App\Http\Middleware\TrimStrings::class,
        //\Illuminate\Foundation\Http\Middleware\ConvertEmptyStringsToNull::class,//會(huì)將''轉(zhuǎn)化為null
        \App\Http\Middleware\TrustProxies::class,
        \Illuminate\Session\Middleware\StartSession::class,
    ];