api: extract http headers with some supported header list. (#2268)

api-headers.go

@@ -62,20 +62,19 @@ func setObjectHeaders(w http.ResponseWriter, objInfo ObjectInfo, contentRange *h
 	// set common headers
 	setCommonHeaders(w)
 
-	// set object-related metadata headers
+	// Set content length.
+	w.Header().Set("Content-Length", strconv.FormatInt(objInfo.Size, 10))
+
+	// Set last modified time.
 	lastModified := objInfo.ModTime.UTC().Format(http.TimeFormat)
 	w.Header().Set("Last-Modified", lastModified)
 
-	if objInfo.ContentType != "" {
-		w.Header().Set("Content-Type", objInfo.ContentType)
-	}
+	// Set Etag if available.
 	if objInfo.MD5Sum != "" {
 		w.Header().Set("ETag", "\""+objInfo.MD5Sum+"\"")
 	}
-	if objInfo.ContentEncoding != "" {
-		w.Header().Set("Content-Encoding", objInfo.ContentEncoding)
-	}
-	w.Header().Set("Content-Length", strconv.FormatInt(objInfo.Size, 10))
+
+	// Set all other user defined metadata.
 	for k, v := range objInfo.UserDefined {
 		w.Header().Set(k, v)
 	}

fs-v1.go

@@ -314,12 +314,15 @@ func (fs fsObjects) GetObjectInfo(bucket, object string) (ObjectInfo, error) {
 		return ObjectInfo{}, toObjectErr(err, bucket, object)
 	}
 
+	if len(fsMeta.Meta) == 0 {
+		fsMeta.Meta = make(map[string]string)
+	}
+
 	// Guess content-type from the extension if possible.
-	contentType := fsMeta.Meta["content-type"]
-	if contentType == "" {
+	if fsMeta.Meta["content-type"] == "" {
 		if objectExt := filepath.Ext(object); objectExt != "" {
 			if content, ok := mimedb.DB[strings.ToLower(strings.TrimPrefix(objectExt, "."))]; ok {
-				contentType = content.ContentType
+				fsMeta.Meta["content-type"] = content.ContentType
 			}
 		}
 	}
@@ -332,7 +335,7 @@ func (fs fsObjects) GetObjectInfo(bucket, object string) (ObjectInfo, error) {
 		Size:            fi.Size,
 		IsDir:           fi.Mode.IsDir(),
 		MD5Sum:          fsMeta.Meta["md5Sum"],
-		ContentType:     contentType,
+		ContentType:     fsMeta.Meta["content-type"],
 		ContentEncoding: fsMeta.Meta["content-encoding"],
 		UserDefined:     fsMeta.Meta,
 	}, nil

handler-utils.go

@@ -19,6 +19,7 @@ package main
 import (
 	"io"
 	"net/http"
+	"strings"
 )
 
 // Validates location constraint in PutBucket request body.
@@ -58,3 +59,39 @@ func isValidLocationConstraint(r *http.Request) (s3Error APIErrorCode) {
 	}
 	return s3Error
 }
+
+// Supported headers that needs to be extracted.
+var supportedHeaders = []string{
+	"content-type",
+	"cache-control",
+	"content-encoding",
+	"content-disposition",
+	// Add more supported headers here.
+}
+
+// extractMetadataFromHeader extracts metadata from HTTP header.
+func extractMetadataFromHeader(header http.Header) map[string]string {
+	metadata := make(map[string]string)
+	// Save standard supported headers.
+	for _, supportedHeader := range supportedHeaders {
+		canonicalHeader := http.CanonicalHeaderKey(supportedHeader)
+		// HTTP headers are case insensitive, look for both canonical
+		// and non canonical entries.
+		if _, ok := header[canonicalHeader]; ok {
+			metadata[supportedHeader] = header.Get(canonicalHeader)
+		} else if _, ok := header[supportedHeader]; ok {
+			metadata[supportedHeader] = header.Get(supportedHeader)
+		}
+	}
+	// Go through all other headers for any additional headers that needs to be saved.
+	for key := range header {
+		cKey := http.CanonicalHeaderKey(key)
+		if strings.HasPrefix(cKey, "X-Amz-Meta-") {
+			metadata[cKey] = header.Get(cKey)
+		} else if strings.HasPrefix(key, "X-Minio-Meta-") {
+			metadata[cKey] = header.Get(cKey)
+		}
+	}
+	// Return.
+	return metadata
+}

handler-utils_test.go

@@ -21,6 +21,7 @@ import (
 	"encoding/xml"
 	"io/ioutil"
 	"net/http"
+	"reflect"
 	"testing"
 )
 
@@ -84,3 +85,36 @@ func TestIsValidLocationContraint(t *testing.T) {
 		}
 	}
 }
+
+// Tests validate metadata extraction from http headers.
+func TestExtractMetadataHeaders(t *testing.T) {
+	testCases := []struct {
+		header   http.Header
+		metadata map[string]string
+	}{
+		// Validate if there a known 'content-type'.
+		{
+			header: http.Header{
+				"Content-Type": []string{"image/png"},
+			},
+			metadata: map[string]string{
+				"content-type": "image/png",
+			},
+		},
+		// Validate if there are no keys to extract.
+		{
+			header: http.Header{
+				"test-1": []string{"123"},
+			},
+			metadata: map[string]string{},
+		},
+	}
+
+	// Validate if the extracting headers.
+	for i, testCase := range testCases {
+		metadata := extractMetadataFromHeader(testCase.header)
+		if !reflect.DeepEqual(metadata, testCase.metadata) {
+			t.Fatalf("Test %d failed: Expected \"%#v\", got \"%#v\"", i+1, testCase.metadata, metadata)
+		}
+	}
+}

object-handlers.go

@@ -325,12 +325,8 @@ func (api objectAPIHandlers) CopyObjectHandler(w http.ResponseWriter, r *http.Re
 	// Save metadata.
 	metadata := make(map[string]string)
 	// Save other metadata if available.
-	if objInfo.ContentType != "" {
-		metadata["content-type"] = objInfo.ContentType
-	}
-	if objInfo.ContentEncoding != "" {
-		metadata["content-encoding"] = objInfo.ContentEncoding
-	}
+	metadata = objInfo.UserDefined
+
 	// Do not set `md5sum` as CopyObject will not keep the
 	// same md5sum as the source.
 
@@ -392,27 +388,10 @@ func (api objectAPIHandlers) PutObjectHandler(w http.ResponseWriter, r *http.Req
 		return
 	}
 
-	// Save metadata.
-	metadata := make(map[string]string)
+	// Extract metadata to be saved from incoming HTTP header.
+	metadata := extractMetadataFromHeader(r.Header)
 	// Make sure we hex encode md5sum here.
 	metadata["md5Sum"] = hex.EncodeToString(md5Bytes)
-	// Save other metadata if available.
-	contentType := r.Header.Get("Content-Type")
-	if contentType != "" {
-		metadata["content-type"] = contentType
-	}
-	contentEncoding := r.Header.Get("Content-Encoding")
-	if contentEncoding != "" {
-		metadata["content-encoding"] = contentEncoding
-	}
-	for key := range r.Header {
-		cKey := http.CanonicalHeaderKey(key)
-		if strings.HasPrefix(cKey, "X-Amz-Meta-") {
-			metadata[cKey] = r.Header.Get(cKey)
-		} else if strings.HasPrefix(key, "X-Minio-Meta-") {
-			metadata[cKey] = r.Header.Get(cKey)
-		}
-	}
 
 	var md5Sum string
 	switch getRequestAuthType(r) {
@@ -472,25 +451,8 @@ func (api objectAPIHandlers) NewMultipartUploadHandler(w http.ResponseWriter, r
 		}
 	}
 
-	// Save metadata.
-	metadata := make(map[string]string)
-	// Save other metadata if available.
-	contentType := r.Header.Get("Content-Type")
-	if contentType != "" {
-		metadata["content-type"] = contentType
-	}
-	contentEncoding := r.Header.Get("Content-Encoding")
-	if contentEncoding != "" {
-		metadata["content-encoding"] = contentEncoding
-	}
-	for key := range r.Header {
-		cKey := http.CanonicalHeaderKey(key)
-		if strings.HasPrefix(cKey, "X-Amz-Meta-") {
-			metadata[cKey] = r.Header.Get(cKey)
-		} else if strings.HasPrefix(key, "X-Minio-Meta-") {
-			metadata[cKey] = r.Header.Get(cKey)
-		}
-	}
+	// Extract metadata that needs to be saved.
+	metadata := extractMetadataFromHeader(r.Header)
 
 	uploadID, err := api.ObjectAPI.NewMultipartUpload(bucket, object, metadata)
 	if err != nil {