How do I put object to amazon s3 using presigned url?

It may help you too :) Add a ContentType property :

s3.getSignedUrl('putObject', {
    Bucket: 'myBucket',
    Expires: 60*60,
    Key: 'myKey',
    ContentType: 'image/jpeg',
}, function (err, url) {
   console.log(url);
});

I managed to succesfully upload a file by using your code.

Here are the steps I followed:

1. Created a new bucket and a new IAM user

2. Set IAM user's policy as below:

   {
       "Version": "2012-10-17",
       "Statement": [
           {
               "Sid": "Stmt1418647210000",
               "Effect": "Allow",
               "Action": [
                   "s3:Put*"
               ],
               "Resource": [
                   "arn:aws:s3:::myBucket/*"
               ]
           }
       ]
   }
   

3. Did NOT create a bucket policy

4. Used your code to generate the pre-signed URL:

   var aws = require('aws-sdk');
   aws.config = {
       accessKeyId: myAccessKeyId,
       secretAccessKey: mySecretAccessKey
   };
   
   var s3 = new aws.s3();
   s3.getSignedUrl('putObject', {
       Bucket: 'myBucket',
       Expires: 60*60,
       Key: 'myKey'
   }, function (err, url) {
       console.log(url);
   });
   

5. Copied the URL on the screen and used curl to test the upload as below:

   curl.exe -k -X PUT -T "someFile" "https://myBucket.s3.amazonaws.com/myKey?AWSAccessKeyId=ACCESS_KEY_ID&Expires=1457632663&Signature=Dhgp40j84yfjBS5v5qSNE4Q6l6U%3D"
   

In my case it generally took 5-10 seconds for the policy changes to take effect so if it fails the first time make sure to keep sending it for a while.

Hope this helps.