PostForm: Save supported headers in obj metadata (#3474)

Supported Headers like Content-Type, Cache-Control, Content-Encoding, X-Amz-* , etc.. are now saved in object metadata

cmd/bucket-handlers.go

@@ -429,9 +429,8 @@ func (api objectAPIHandlers) PostPolicyBucketHandler(w http.ResponseWriter, r *h
 		}
 	}
 
-	// Save metadata.
-	metadata := make(map[string]string)
-	// Nothing to store right now.
+	// Extract metadata to be saved from received Form.
+	metadata := extractMetadataFromForm(formValues)
 
 	sha256sum := ""
 

cmd/handler-utils.go

@@ -92,6 +92,32 @@ func extractMetadataFromHeader(header http.Header) map[string]string {
 	return metadata
 }
 
+// extractMetadataFromForm extracts metadata from Post Form.
+func extractMetadataFromForm(formValues map[string]string) map[string]string {
+	metadata := make(map[string]string)
+	// Save standard supported headers.
+	for _, supportedHeader := range supportedHeaders {
+		canonicalHeader := http.CanonicalHeaderKey(supportedHeader)
+		// Form field names are case insensitive, look for both canonical
+		// and non canonical entries.
+		if _, ok := formValues[canonicalHeader]; ok {
+			metadata[supportedHeader] = formValues[canonicalHeader]
+		} else if _, ok := formValues[supportedHeader]; ok {
+			metadata[supportedHeader] = formValues[canonicalHeader]
+		}
+	}
+	// Go through all other form values for any additional headers that needs to be saved.
+	for key := range formValues {
+		cKey := http.CanonicalHeaderKey(key)
+		if strings.HasPrefix(cKey, "X-Amz-Meta-") {
+			metadata[cKey] = formValues[key]
+		} else if strings.HasPrefix(cKey, "X-Minio-Meta-") {
+			metadata[cKey] = formValues[key]
+		}
+	}
+	return metadata
+}
+
 // Extract form fields and file data from a HTTP POST Policy
 func extractPostPolicyFormValues(reader *multipart.Reader) (filePart io.Reader, fileName string, formValues map[string]string, err error) {
 	/// HTML Form values

cmd/post-policy_test.go

@@ -178,6 +178,7 @@ func testPostPolicyBucketHandler(obj ObjectLayer, instanceType string, t TestErr
 	testCasesV4 := []struct {
 		objectName         string
 		data               []byte
+		expectedHeaders    map[string]string
 		expectedRespStatus int
 		accessKey          string
 		secretKey          string
@@ -188,6 +189,7 @@ func testPostPolicyBucketHandler(obj ObjectLayer, instanceType string, t TestErr
 			objectName:         "test",
 			data:               []byte("Hello, World"),
 			expectedRespStatus: http.StatusNoContent,
+			expectedHeaders:    map[string]string{"X-Amz-Meta-Uuid": "1234"},
 			accessKey:          credentials.AccessKeyID,
 			secretKey:          credentials.SecretAccessKey,
 			malformedBody:      false,
@@ -229,6 +231,18 @@ func testPostPolicyBucketHandler(obj ObjectLayer, instanceType string, t TestErr
 		if rec.Code != testCase.expectedRespStatus {
 			t.Errorf("Test %d: %s: Expected the response status to be `%d`, but instead found `%d`", i+1, instanceType, testCase.expectedRespStatus, rec.Code)
 		}
+		// When the operation is successful, check if sending metadata is successful too
+		if rec.Code == http.StatusNoContent {
+			objInfo, err := obj.GetObjectInfo(bucketName, testCase.objectName+"/upload.txt")
+			if err != nil {
+				t.Error("Unexpected error: ", err)
+			}
+			for k, v := range testCase.expectedHeaders {
+				if objInfo.UserDefined[k] != v {
+					t.Errorf("Expected to have header %s with value %s, but found value `%s` instead", k, v, objInfo.UserDefined[k])
+				}
+			}
+		}
 	}
 
 	// Test cases for signature-V4.
@@ -475,6 +489,8 @@ func newPostRequestV4Generic(endPoint, bucketName, objectName string, objData []
 		"x-amz-signature":  signature,
 		"x-amz-date":       t.Format(iso8601DateFormat),
 		"x-amz-algorithm":  "AWS4-HMAC-SHA256",
+		"x-amz-meta-uuid":  "1234",
+		"Content-Encoding": "gzip",
 	}
 
 	// Create the multipart form.