Upload error: Could not contact request signing server

[sgtpepper908]

In Node.js, where do I pass my access key and secret access key? Is it automatically detected by AWS-SDK? I created AWS.config but I don't see it being used in the example.

app.use('/s3', require('react-s3-uploader/s3router')({
    bucket: "MyS3Bucket",
    region: 'us-east-1', //optional
    signatureVersion: 'v4', //optional (use for some amazon regions: frankfurt and others)
    signatureExpires: 60, //optional, number of seconds the upload signed URL should be valid for (defaults to 60)
    headers: {'Access-Control-Allow-Origin': '*'}, // optional
    ACL: 'private', // this is default
    uniquePrefix: true // (4.0.2 and above) default is true, setting the attribute to false preserves the original filename in S3
}));

Upload error: Could not contact request signing server. Status = 0