title: Is using S3 Metadata Request to get ETag possible?
body: <p>The thing is that I need to get the etag information from Amazon before I actually get the file itself. </p>
  
  <p>After researching I found that the right way is using S3GetObjectMetadataRequest and later getObjectMetadata to fetch a S3GetObjectMetadataResponse object.</p>
  
  <p>But when trying to create a S3GetObjectMetadataRequest with: </p>
  
  <p><code>S3GetObjectMetadataRequest *metadata = [[S3GetObjectMetadataRequest alloc] initWithKey:key withBucket:bucket];</code></p>
  
  <p>a strong warning is showed:</p>
  
  <p><code>incompatible Objective-C types initializing 'struct S3GetObjectRequest *', expected 'struct S3GetObjectMetadataRequest *'</code></p>
  
  <p>The documentation on S3GetObjectMetadataRequest is absent and I couldn't find any reference on this anywhere.</p>
  
  <p>Am I overlooking this? Is there a easier way to get the ETag without having to download all the file?</p>