AWS S3签名不匹配

Question

我被卡在s3.getSignedUrl上，并收到错误消息“签名不匹配，计算出的签名不匹配...”。我已经检查了凭据以及许多其他内容，但是没有取得任何进展。我的访问密钥和机密已保存在凭证文件中。

我返回的网址是https://postcard-photo-repo-dev.s3.amazonaws.com/Screenshot7.png?AWSAccessKeyId=AKIAJWHTSREEZUZGGO3A&Expires=1534619652&Signature=MkyVjARuo3PaO6lAYV6Li%2FAaR9E%3D

upload.js文件：

function getSignedRequest(file) {
    const xhr = new XMLHttpRequest();
    xhr.open('GET', `/api/feed/sign-s3?file-name=${file.name}&file-type=${file.type}`);
    xhr.onreadystatechange = () => {
        if(xhr.readyState === 4){
            if(xhr.status === 200){
                const response = JSON.parse(xhr.responseText);
                uploadFile(file, response.signedRequest, response.url);
            } else {
                alert('Could not get signed URL');
            }
        }
    };
    xhr.send();
}

function uploadFile(file, signedRequest, url){
    const xhr = new XMLHttpRequest();
    xhr.open('PUT', signedRequest);
    xhr.onreadystatechange = () => {
        if(xhr.readyState === 4) {
            if(xhr.status === 200) {
                $('#preview').src = url;
                $('#avatar-url').value = url;
            } else {
                alert('Could not upload file');
            }
        }
    };
    xhr.send(file);
}

路由文件：

router.get('/sign-s3', (req, res) => {
    const s3 = new aws.S3();
    const fileName = req.query['file-name'];
    const fileType = req.query['file-type'];
    const s3Params = {
        Bucket: S3_BUCKET,
        Key: fileName,
        Expires: 600,
        // ACL: 'public-read',
        // ContentType: fileType
    };

    s3.getSignedUrl('putObject', s3Params, (err, data) => {
        if(err) {
            console.log(err);
            return res.end();
        }
        console.log(data);
        const returnData = {
            signedRequest: data,
            url: `https://${S3_BUCKET}.s3.amazonaws.com/${fileName}`
        };
        res.write(JSON.stringify(returnData));
        res.end();
    });
});