Getting Missing Key-Pair-Id query parameter or cookie value error from cloudfront

Question

Using cloudfront to serve private content from s3 bucket using signed cookies. I am able to generate cookies, but when i request a resource, i get Missing Key-Pair-Id query parameter or cookie value error, either from node.js or even any client/browser/postman

const cloudFront = new AWS.CloudFront.Signer(
  fs.readFileSync('./rsa-APKAIQSVJ2R3T6PYTOUQ.pem', 'utf8'),
  fs.readFileSync('./pk-APKAIQSVJ2R3T6PYTOUQ.pem', 'utf8')
);

const policy = JSON.stringify({
  Statement: [{
    Resource: 'http*://d2q89b5pewg0ry.cloudfront.net/images/',
    Condition: {
      DateLessThan: {
        'AWS:EpochTime': Math.floor(new Date().getTime() / 1000) + 60 * 60 * 3
      }
    },
  }]
});

const cookie = cloudFront.getSignedCookie({
  policy: policy
});

let cookieString = '';
for(var cookieKey in cookie)
{
  cookieString += cookieKey + '=' + cookie[cookieKey] + ";";
}
return axios.get('https://d2q89b5pewg0ry.cloudfront.net/images/hikup.jpg',{
  headers: {
    Cookie: cookieString
  }
}).then((response) => {
  return response;
}).catch((error) => {
  return error;
});

Answer 1

You're not using the full constructor, check below:

CloudFront signed cookies node,js

The cookies should have 3 keys and their values:

CloudFront-Expires
CloudFront-Signature
CloudFront-Key-Pair-Id

You also need to add cookie/key CloudFront-Key-Pair-Id= APKAIQSVJ2R3T6PYTOUQ when making the request.

The CloudFront-Key-Pair-Id is not the public key, it just the ID(like an access key ID) so CloudFront can see which public key it needs to decrypt the signature. You can have up to 2 keys active on CloudFront and you create the signature with private key and Public key is with CloudFront, when cloudfront receives the request, it checks the CloudFront-Key-Pair-Id to know which public it should use, so end of story, the CloudFront-Key-Pair-Id is the ID when you login to AWS console and go to Security Credentials and click CloudFront Keypairs, You'll see a Access Key ID, thats one you need to define. (which is same as the file name)