fix: CopyObject with URL-encoded special chars

CopyObject was failing with NoSuchKey when source keys contained special
characters like {} or spaces. The X-Amz-Copy-Source header is URL-encoded
by clients, but ParseCopySource wasn't decoding before filesystem access.

Added url.QueryUnescape() to properly decode bucket and object names,
fixing copy operations for keys with special characters.

Fixing this also uncovered an errors with azure blob url encoding with
similar special character handling. Added this fix in for the integration
tests to pass.

Fixes #1832
Fixes #1637

tests/integration/CopyObject.go

@@ -1498,6 +1498,96 @@ func CopyObject_success(s *S3Conf) error {
 	})
 }
 
+func CopyObject_with_special_characters(s *S3Conf) error {
+	testName := "CopyObject_with_special_characters"
+	return actionHandler(s, testName, func(s3client *s3.Client, bucket string) error {
+		// Test copying objects with special characters that need URL encoding
+		// like curly braces, spaces, and other reserved characters
+		testCases := []struct {
+			name   string
+			srcKey string
+			dstKey string
+		}{
+			{
+				name:   "curly braces",
+				srcKey: "myfolder/{e14c392b-09ad-4188-85f4-b779af00fb88}/testfile",
+				dstKey: "myfolder/{e14c392b-09ad-4188-85f4-b779af00fb88}/copy",
+			},
+			{
+				name:   "multiple special chars",
+				srcKey: "folder/{id}/file #1",
+				dstKey: "folder/{id}/file #1 copy",
+			},
+			{
+				name:   "ampersand and hash",
+				srcKey: "file&with#special",
+				dstKey: "file&with#special-copy",
+			},
+			{
+				name:   "spaces and brackets",
+				srcKey: "my file [2024].txt",
+				dstKey: "my file [2024] copy.txt",
+			},
+		}
+
+		for _, tc := range testCases {
+			// Create source object
+			dataLength := int64(100)
+			r, err := putObjectWithData(dataLength, &s3.PutObjectInput{
+				Bucket: &bucket,
+				Key:    &tc.srcKey,
+			}, s3client)
+			if err != nil {
+				return fmt.Errorf("%s: failed to put source object: %w", tc.name, err)
+			}
+
+			// Copy the object
+			ctx, cancel := context.WithTimeout(context.Background(), shortTimeout)
+			_, err = s3client.CopyObject(ctx, &s3.CopyObjectInput{
+				Bucket:     &bucket,
+				Key:        &tc.dstKey,
+				CopySource: getPtr(fmt.Sprintf("%v/%v", bucket, tc.srcKey)),
+			})
+			cancel()
+			if err != nil {
+				return fmt.Errorf("%s: failed to copy object: %w", tc.name, err)
+			}
+
+			// Verify the copied object
+			ctx, cancel = context.WithTimeout(context.Background(), shortTimeout)
+			out, err := s3client.GetObject(ctx, &s3.GetObjectInput{
+				Bucket: &bucket,
+				Key:    &tc.dstKey,
+			})
+			cancel()
+			if err != nil {
+				return fmt.Errorf("%s: failed to get copied object: %w", tc.name, err)
+			}
+
+			if out.ContentLength == nil {
+				return fmt.Errorf("%s: expected content-length to be set, instead got nil", tc.name)
+			}
+			if *out.ContentLength != dataLength {
+				return fmt.Errorf("%s: expected content-length %v, instead got %v",
+					tc.name, dataLength, *out.ContentLength)
+			}
+
+			bdy, err := io.ReadAll(out.Body)
+			if err != nil {
+				return fmt.Errorf("%s: failed to read body: %w", tc.name, err)
+			}
+			out.Body.Close()
+
+			outCsum := sha256.Sum256(bdy)
+			if outCsum != r.csum {
+				return fmt.Errorf("%s: invalid object data, checksum mismatch", tc.name)
+			}
+		}
+
+		return nil
+	})
+}
+
 func CopyObject_object_acl_not_supported(s *S3Conf) error {
 	testName := "CopyObject_object_acl_not_supported"
 	return actionHandler(s, testName, func(s3client *s3.Client, bucket string) error {

tests/integration/group-tests.go

@@ -347,6 +347,7 @@ func TestCopyObject(ts *TestState) {
 		// azure doesn't support these metadata characters
 		ts.Run(CopyObject_with_metadata)
 	}
+	ts.Run(CopyObject_with_special_characters)
 	ts.Run(CopyObject_success)
 }
 
@@ -1404,6 +1405,7 @@ func GetIntTests() IntTests {
 		"CopyObject_should_copy_the_existing_checksum":                             CopyObject_should_copy_the_existing_checksum,
 		"CopyObject_should_replace_the_existing_checksum":                          CopyObject_should_replace_the_existing_checksum,
 		"CopyObject_to_itself_by_replacing_the_checksum":                           CopyObject_to_itself_by_replacing_the_checksum,
+		"CopyObject_with_special_characters":                                       CopyObject_with_special_characters,
 		"CopyObject_success":                                                       CopyObject_success,
 		"PutObjectTagging_non_existing_object":                                     PutObjectTagging_non_existing_object,
 		"PutObjectTagging_long_tags":                                               PutObjectTagging_long_tags,