Option to preserve file mtime on save

mutagen/_iff.py

@@ -20,6 +20,7 @@
     delete_bytes,
     insert_bytes,
     loadfile,
+    set_restore_mtime,
     reraise,
     resize_bytes,
 )
@@ -364,11 +365,14 @@ def _pre_load_header(self, fileobj):
 
     @convert_error(IOError, error)
     @loadfile(writable=True)
-    def save(self, filething=None, v2_version=4, v23_sep='/', padding=None):
+    def save(self, filething=None, v2_version=4, v23_sep='/',
+    padding=None, preserve_mtime=False):
         """Save ID3v2 data to the IFF file"""
-
         fileobj = filething.fileobj
 
+        if preserve_mtime:
+            set_restore_mtime(fileobj)
+
         iff_file = self._load_file(fileobj)
 
         if 'ID3' not in iff_file:

mutagen/_util.py

@@ -16,6 +16,8 @@
 import codecs
 import errno
 import decimal
+import os
+import time
 from io import BytesIO
 from typing import Tuple, List
 
@@ -271,21 +273,35 @@ def _openfile(instance, filething, filename, fileobj, writable, create):
             else:
                 raise MutagenError(e)
 
-        with fileobj as fileobj:
-            yield FileThing(fileobj, filename, filename)
-
-            if inmemory_fileobj:
-                assert writable
-                data = fileobj.getvalue()
-                try:
-                    with open(filename, "wb") as fileobj:
-                        fileobj.write(data)
-                except IOError as e:
-                    raise MutagenError(e)
+        try:
+            with fileobj as fileobj:
+                yield FileThing(fileobj, filename, filename)
+
+                if inmemory_fileobj:
+                    assert writable
+                    data = fileobj.getvalue()
+                    try:
+                        with open(filename, "wb") as fileobj:
+                            fileobj.write(data)
+                    except IOError as e:
+                        raise MutagenError(e)
+        finally:
+            if hasattr(fileobj, "__restore_mtime__"):
+                new_atime = time.time_ns()
+                original_mtime = fileobj.__restore_mtime__
+                print("\nRetaining original mtime. file={}, atime={}, o_mtime={}"
+                .format(filename, new_atime, original_mtime))
+                os.utime(filename, ns=(new_atime, original_mtime))
     else:
         raise TypeError("Missing filename or fileobj argument")
 
 
+def set_restore_mtime(fileobj):
+    if fileobj is not None:
+        original_mtime = os.stat(fileobj.name).st_mtime_ns
+        setattr(fileobj, "__restore_mtime__", original_mtime)
+
+
 class MutagenError(Exception):
     """Base class for all custom exceptions in mutagen
 

mutagen/apev2.py

@@ -36,7 +36,8 @@
 
 from mutagen import Metadata, FileType, StreamInfo
 from mutagen._util import DictMixin, cdata, delete_bytes, total_ordering, \
-    MutagenError, loadfile, convert_error, seek_end, get_size, reraise
+    MutagenError, loadfile, convert_error, seek_end, get_size, reraise, \
+    set_restore_mtime
 
 
 def is_valid_apev2_key(key):
@@ -396,7 +397,7 @@ def __setitem__(self, key, value):
 
     @convert_error(IOError, error)
     @loadfile(writable=True, create=True)
-    def save(self, filething=None):
+    def save(self, filething=None, preserve_mtime=False):
         """Save changes to a file.
 
         If no filename is given, the one most recently loaded is used.
@@ -407,6 +408,9 @@ def save(self, filething=None):
 
         fileobj = filething.fileobj
 
+        if preserve_mtime:
+            set_restore_mtime(fileobj)
+
         data = _APEv2Data(fileobj)
 
         if data.is_at_start:

mutagen/asf/__init__.py

@@ -11,7 +11,8 @@
 __all__ = ["ASF", "Open"]
 
 from mutagen import FileType, Tags, StreamInfo
-from mutagen._util import resize_bytes, DictMixin, loadfile, convert_error
+from mutagen._util import resize_bytes, DictMixin, loadfile, convert_error, \
+    set_restore_mtime
 
 from ._util import error, ASFError, ASFHeaderError
 from ._objects import HeaderObject, MetadataLibraryObject, MetadataObject, \
@@ -245,7 +246,7 @@ def load(self, filething):
 
     @convert_error(IOError, error)
     @loadfile(writable=True)
-    def save(self, filething=None, padding=None):
+    def save(self, filething=None, padding=None, preserve_mtime=False):
         """save(filething=None, padding=None)
 
         Save tag changes back to the loaded file.
@@ -300,6 +301,9 @@ def save(self, filething=None, padding=None):
             header_ext.objects.append(MetadataLibraryObject())
 
         fileobj = filething.fileobj
+        if preserve_mtime:
+            set_restore_mtime(fileobj)
+
         # Render to file
         old_size = header.parse_size(fileobj)[0]
         data = header.render_full(self, fileobj, old_size, padding)

mutagen/dsf.py

@@ -14,7 +14,7 @@
 
 from mutagen import FileType, StreamInfo
 from mutagen._util import cdata, MutagenError, loadfile, \
-    convert_error, reraise, endswith
+    convert_error, reraise, endswith, set_restore_mtime
 from mutagen.id3 import ID3
 from mutagen.id3._util import ID3NoHeaderError, error as ID3Error
 
@@ -198,10 +198,15 @@ def _pre_load_header(self, fileobj):
 
     @convert_error(IOError, error)
     @loadfile(writable=True)
-    def save(self, filething=None, v2_version=4, v23_sep='/', padding=None):
+    def save(self, filething=None, v2_version=4, v23_sep='/', padding=None,
+            preserve_mtime=False):
         """Save ID3v2 data to the DSF file"""
 
         fileobj = filething.fileobj
+
+        if preserve_mtime:
+            set_restore_mtime(fileobj)
+
         fileobj.seek(0)
 
         dsd_header = DSDChunk(fileobj)

mutagen/easyid3.py

@@ -174,8 +174,9 @@ def __init__(self, filename=None):
 
     @loadfile(writable=True, create=True)
     def save(self, filething=None, v1=1, v2_version=4, v23_sep='/',
-             padding=None):
-        """save(filething=None, v1=1, v2_version=4, v23_sep='/', padding=None)
+             padding=None, preserve_mtime=False):
+        """save(filething=None, v1=1, v2_version=4, v23_sep='/', padding=None,
+                preserve_mtime=False)
 
         Save changes to a file.
         See :meth:`mutagen.id3.ID3.save` for more info.
@@ -191,12 +192,13 @@ def save(self, filething=None, v1=1, v2_version=4, v23_sep='/',
                 self.__id3.update_to_v23()
                 self.__id3.save(
                     filething, v1=v1, v2_version=v2_version, v23_sep=v23_sep,
-                    padding=padding)
+                    padding=padding, preserve_mtime=preserve_mtime)
             finally:
                 self.__id3._restore(backup)
         else:
             self.__id3.save(filething, v1=v1, v2_version=v2_version,
-                            v23_sep=v23_sep, padding=padding)
+                            v23_sep=v23_sep, padding=padding,
+                            preserve_mtime=preserve_mtime)
 
     delete = property(lambda s: s.__id3.delete,
                       lambda s, v: setattr(s.__id3, 'delete', v))

mutagen/flac.py

@@ -27,7 +27,7 @@
 import mutagen
 
 from mutagen._util import resize_bytes, MutagenError, get_size, loadfile, \
-    convert_error, bchr, endswith
+    convert_error, bchr, endswith, set_restore_mtime
 from mutagen._tags import PaddingInfo
 from mutagen.id3._util import BitPaddedInt
 from functools import reduce
@@ -836,13 +836,14 @@ def pictures(self):
 
     @convert_error(IOError, error)
     @loadfile(writable=True)
-    def save(self, filething=None, deleteid3=False, padding=None):
+    def save(self, filething=None, deleteid3=False, padding=None, preserve_mtime=False):
         """Save metadata blocks to a file.
 
         Args:
             filething (filething)
             deleteid3 (bool): delete id3 tags while at it
             padding (:obj:`mutagen.PaddingFunction`)
+            preserve_mtime (bool): Keep existing modified time on save
 
         If no filename is given, the one most recently loaded is used.
         """
@@ -856,6 +857,9 @@ def save(self, filething=None, deleteid3=False, padding=None):
                 raise ValueError("Invalid seektable object type!")
             self.metadata_blocks.append(self.seektable)
 
+        if preserve_mtime:
+            set_restore_mtime(filething.fileobj)
+
         self._save(filething, self.metadata_blocks, deleteid3, padding)
 
     def _save(self, filething, metadata_blocks, deleteid3, padding):

mutagen/id3/_file.py

@@ -11,7 +11,7 @@
 
 import mutagen
 from mutagen._util import insert_bytes, delete_bytes, enum, \
-    loadfile, convert_error, read_full
+    loadfile, convert_error, read_full, set_restore_mtime
 from mutagen._tags import PaddingInfo
 
 from ._util import error, ID3NoHeaderError, ID3UnsupportedVersionError, \
@@ -221,8 +221,9 @@ def _prepare_data(self, fileobj, start, available, v2_version, v23_sep,
     @convert_error(IOError, error)
     @loadfile(writable=True, create=True)
     def save(self, filething=None, v1=1, v2_version=4, v23_sep='/',
-             padding=None):
-        """save(filething=None, v1=1, v2_version=4, v23_sep='/', padding=None)
+             padding=None, preserve_mtime=False):
+        """save(filething=None, v1=1, v2_version=4, v23_sep='/', padding=None,
+                preserve_mtime=False)
 
         Save changes to a file.
 
@@ -241,6 +242,8 @@ def save(self, filething=None, v1=1, v2_version=4, v23_sep='/',
                 if v2_version == 3. Defaults to '/' but if it's None
                 will be the ID3v2v2.4 null separator.
             padding (:obj:`mutagen.PaddingFunction`)
+            preserve_mtime:
+                Keep the original file modified time as it was before saving.
 
         Raises:
             mutagen.MutagenError
@@ -253,6 +256,9 @@ def save(self, filething=None, v1=1, v2_version=4, v23_sep='/',
 
         f = filething.fileobj
 
+        if preserve_mtime:
+            set_restore_mtime(f)
+
         try:
             header = ID3Header(filething.fileobj)
         except ID3NoHeaderError:

mutagen/mp4/__init__.py

@@ -32,7 +32,7 @@
 from mutagen._constants import GENRES
 from mutagen._util import cdata, insert_bytes, DictProxy, MutagenError, \
     hashable, enum, get_size, resize_bytes, loadfile, convert_error, bchr, \
-    reraise
+    reraise, set_restore_mtime
 from ._atom import Atoms, Atom, AtomError
 from ._util import parse_full_atom
 from ._as_entry import AudioSampleEntry, ASEntryError
@@ -389,7 +389,7 @@ def _render(self, key, value):
 
     @convert_error(IOError, error)
     @loadfile(writable=True)
-    def save(self, filething=None, padding=None):
+    def save(self, filething=None, padding=None, preserve_mtime=False):
 
         values = []
         items = sorted(self.items(), key=lambda kv: _item_sort_key(*kv))
@@ -418,7 +418,10 @@ def save(self, filething=None, padding=None):
         except AtomError as err:
             reraise(error, err, sys.exc_info()[2])
 
-        self.__save(filething.fileobj, atoms, data, padding)
+        fileobj = filething.fileobj
+        if preserve_mtime:
+            set_restore_mtime(fileobj)
+        self.__save(fileobj, atoms, data, padding)
 
     def __save(self, fileobj, atoms, data, padding):
         try:

mutagen/ogg.py

@@ -23,7 +23,7 @@
 
 from mutagen import FileType
 from mutagen._util import cdata, resize_bytes, MutagenError, loadfile, \
-    seek_end, bchr, reraise
+    seek_end, bchr, reraise, set_restore_mtime
 from mutagen._file import StreamInfo
 from mutagen._tags import Tags
 
@@ -571,8 +571,8 @@ def add_tags(self):
         raise self._Error
 
     @loadfile(writable=True)
-    def save(self, filething=None, padding=None):
-        """save(filething=None, padding=None)
+    def save(self, filething=None, padding=None, preserve_mtime=False):
+        """save(filething=None, padding=None. preserve_mtime=False))
 
         Save a tag to a file.
 
@@ -581,11 +581,15 @@ def save(self, filething=None, padding=None):
         Args:
             filething (filething)
             padding (:obj:`mutagen.PaddingFunction`)
+            preserve_mtime (bool)
         Raises:
             mutagen.MutagenError
         """
 
         try:
+            if preserve_mtime:
+                set_restore_mtime(filething.fileobj)
+
             self.tags._inject(filething.fileobj, padding)
         except (IOError, error) as e:
             reraise(self._Error, e, sys.exc_info()[2])

mutagen/wave.py

@@ -22,6 +22,7 @@
     endswith,
     loadfile,
     reraise,
+    set_restore_mtime
 )
 
 __all__ = ["WAVE", "Open", "delete"]
@@ -118,10 +119,15 @@ def _pre_load_header(self, fileobj):
 
     @convert_error(IOError, error)
     @loadfile(writable=True)
-    def save(self, filething, v1=1, v2_version=4, v23_sep='/', padding=None):
+    def save(self, filething, v1=1, v2_version=4, v23_sep='/', padding=None,
+            preserve_mtime=False):
         """Save ID3v2 data to the Wave/RIFF file"""
 
         fileobj = filething.fileobj
+
+        if preserve_mtime:
+            set_restore_mtime(fileobj)
+
         wave_file = _WaveFile(fileobj)
 
         if u'id3' not in wave_file:

tests/__init__.py

@@ -35,6 +35,16 @@ def get_temp_copy(path):
     return filename
 
 
+def get_temp_copy_keep_metadata(path):
+    """Returns a copy of the file with the same extension"""
+
+    ext = os.path.splitext(path)[-1]
+    fd, filename = mkstemp(suffix=ext)
+    os.close(fd)
+    shutil.copy2(path, filename)
+    return filename
+
+
 def get_temp_empty(ext=""):
     """Returns an empty file with the extension"""