Remove Content-Encoding header follow aws-sdk-java

Added benefit is AWS S3 doesn't return wrong empty
Content-Encoding, this is possibly an AWS S3 bug.

Fixes #758

pkg/s3signer/request-signature-streaming.go

@@ -32,7 +32,6 @@ import (
 // http://docs.aws.amazon.com/AmazonS3/latest/API/sigv4-streaming.html#example-signature-calculations-streaming
 const (
 	streamingSignAlgorithm = "STREAMING-AWS4-HMAC-SHA256-PAYLOAD"
-	streamingEncoding      = "aws-chunked"
 	streamingPayloadHdr    = "AWS4-HMAC-SHA256-PAYLOAD"
 	emptySHA256            = "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"
 	payloadChunkSize       = 64 * 1024
@@ -99,9 +98,8 @@ func prepareStreamingRequest(req *http.Request, sessionToken string, dataLen int
 	if sessionToken != "" {
 		req.Header.Set("X-Amz-Security-Token", sessionToken)
 	}
-	req.Header.Add("Content-Encoding", streamingEncoding)
-	req.Header.Set("X-Amz-Date", timestamp.Format(iso8601DateFormat))
 
+	req.Header.Set("X-Amz-Date", timestamp.Format(iso8601DateFormat))
 	// Set content length with streaming signature for each chunk included.
 	req.ContentLength = getStreamLength(dataLen, int64(payloadChunkSize))
 	req.Header.Set("x-amz-decoded-content-length", strconv.FormatInt(dataLen, 10))

pkg/s3signer/request-signature-streaming_test.go

@@ -42,7 +42,7 @@ func TestGetSeedSignature(t *testing.T) {
 	req = StreamingSignV4(req, accessKeyID, secretAccessKeyID, "", "us-east-1", int64(dataLen), reqTime)
 	actualSeedSignature := req.Body.(*StreamingReader).seedSignature
 
-	expectedSeedSignature := "007480502de61457e955731b0f5d191f7e6f54a8a0f6cc7974a5ebd887965686"
+	expectedSeedSignature := "38cab3af09aa15ddf29e26e36236f60fb6bfb6243a20797ae9a8183674526079"
 	if actualSeedSignature != expectedSeedSignature {
 		t.Errorf("Expected %s but received %s", expectedSeedSignature, actualSeedSignature)
 	}
@@ -74,7 +74,7 @@ func TestSetStreamingAuthorization(t *testing.T) {
 	reqTime, _ := time.Parse(iso8601DateFormat, "20130524T000000Z")
 	req = StreamingSignV4(req, accessKeyID, secretAccessKeyID, "", location, dataLen, reqTime)
 
-	expectedAuthorization := "AWS4-HMAC-SHA256 Credential=AKIAIOSFODNN7EXAMPLE/20130524/us-east-1/s3/aws4_request,SignedHeaders=content-encoding;host;x-amz-content-sha256;x-amz-date;x-amz-decoded-content-length;x-amz-storage-class,Signature=007480502de61457e955731b0f5d191f7e6f54a8a0f6cc7974a5ebd887965686"
+	expectedAuthorization := "AWS4-HMAC-SHA256 Credential=AKIAIOSFODNN7EXAMPLE/20130524/us-east-1/s3/aws4_request,SignedHeaders=host;x-amz-content-sha256;x-amz-date;x-amz-decoded-content-length;x-amz-storage-class,Signature=38cab3af09aa15ddf29e26e36236f60fb6bfb6243a20797ae9a8183674526079"
 
 	actualAuthorization := req.Header.Get("Authorization")
 	if actualAuthorization != expectedAuthorization {