hdk-core/src/Service/OssService.php

<?php
/**
 * OssService.php@LuxStudio
 *
 * @author 李东云<dongyun.li@luxcreo.cn>
 * Powered by PhpStorm
 * Created on 2022/5/11
 */

namespace Singularity\HDK\Core\Service;

use Hyperf\Codec\Json;

use function Hyperf\Config\config;

class OssService
{
    /**
     * @param string|null $accessKeyId 不传则取配置文件
     * @param string|null $accessKeySecret 不传则取配置文件
     * @param string|null $host 不传则取配置文件
     * @param int|null $expiration 过期时间，默认30s
     */
    public function __construct(
        public ?string $accessKeyId = null,
        public ?string $accessKeySecret = null,
        public ?string $host = null,
        public ?string $callbackUrl = null,
        public ?int $expiration = 30
    ) {
        $this->accessKeyId ??= config('common.third_party.storage.oss.access_key_id');
        $this->accessKeySecret ??= config('common.third_party.storage.oss.access_key_secret');
        $this->host ??= config('common.third_party.storage.oss.oss_host');
        $this->callbackUrl ??= config('common.third_party.storage.oss.oss_callback') ?? null;
    }

    /**
     * 生成签证
     *
     * @param string|null $dir
     * @param bool $isImage
     * @param int $maxFileSize 最大文件大小（单位：b）
     *
     * @return array{
     *     'accessid' : string,
     *     'host' : string,
     *     'policy': string,
     *     'signature': string,
     *     'expire' : int,
     *     'dir' : string,
     *     'callback':string
     * }
     */
    public function generatePolicy(
        string $dir = null,
        bool $isImage = false,
        int $maxFileSize = 1048576000
    ): array {
        $expire_time = time() + $this->expiration;
        $expiration = $this->gmtIso8601($expire_time);

        //最大文件大小.用户可以自己设置
        $condition = [
            0 => 'Content-Length-Range',
            1 => 0,
            2 => $maxFileSize,
        ];
        $conditions[] = $condition;

        // 表示用户上传的数据，必须是以$dir开始，不然上传会失败，这一步不是必须项，只是为了安全起见，防止用户通过policy上传到别人的目录。
        if ($dir) {
            $start = [
                0 => 'starts-with',
                1 => '$key',
                2 => $dir,
            ];
            $conditions[] = $start;
        }


        $policy = Json::encode([
            'expiration' => $expiration,
            'conditions' => $conditions,
        ]);
        $base64_policy = base64_encode($policy);
        $string_to_sign = $base64_policy;
        $signature = base64_encode(hash_hmac('sha1', $string_to_sign, $this->accessKeySecret, true));

        $callback = isset($this->callbackUrl) ? Json::encode([
            'callbackUrl' => $this->callbackUrl,
            'callbackBody' => $isImage ? <<<'callbackBody'
{
    "bucket": ${bucket},
    "object": ${object},
    "etag": ${etag},
    "size": ${size},
    "mimeType": ${mimeType},
    "imageInfo": {
        "height": ${imageInfo.height},
        "width": ${imageInfo.width},
        "format": ${imageInfo.format}
    },
    "uid": ${x:uid},
    "name": ${x:name},
    "hash": ${x:hash}
}
callbackBody : <<<'callbackBody'
{
    "bucket": ${bucket},
    "object": ${object},
    "etag": ${etag},
    "size": ${size},
    "mimeType": ${mimeType},
    "uid": ${x:uid},
    "name": ${x:name},
    "hash": ${x:hash}
}
callbackBody,
            'callbackBodyType' => 'application/json',
        ]) : null;

        $result = [
            'accessid' => $this->accessKeyId,
            'host' => $this->host,
            'policy' => $base64_policy,
            'signature' => $signature,
            'expire' => $expire_time,
            'dir' => $dir,
        ];
        if (isset($callback)) {
            $result += ['callback' => base64_encode($callback),];
        }
        return $result;
    }

    /**
     * 将时间戳转化为 ISO8601 格式
     *
     * @param int $time
     *
     * @return string
     */
    protected function gmtIso8601(int $time): string
    {
        return str_replace('+00:00', '.000Z', gmdate('c', $time));
    }
}