Encountered an interesting issue with vobject. Calling 'v.serialize()' multiple times results in unexpected errors.

[Gerald-Meyers]

So I was modifying a vcf file I made on my phone and just trying out the vobject module to do so. I was trying to save a file but kept getting type errors pointing back to vobject's base.py.

'Gerald Meyers'
TypeError: a bytes-like object is required, not 'str'
v.serialize() output:

TypeError Traceback (most recent call last)
Cell In[14], line 4
2 with open(my_card, 'wb') as card:
3 # card.write(serialized.encode('utf-8'))
----> 4 card.write(v.serialize().encode('utf-8'))
5 except TypeError as e:

File c:\ProgramData\miniconda3\lib\site-packages\vobject\base.py:254, in VBase.serialize(self, buf, lineLength, validate, behavior)
253 logger.debug("serializing {0!s} with behavior {1!s}".format(self.name, behavior))
--> 254 return behavior.serialize(self, buf, lineLength, validate)
255 else:

File c:\ProgramData\miniconda3\lib\site-packages\vobject\behavior.py:166, in Behavior.serialize(cls, obj, buf, lineLength, validate)
164 undoTransform = False
--> 166 out = base.defaultSerialize(transformed, buf, lineLength)
167 if undoTransform:

File c:\ProgramData\miniconda3\lib\site-packages\vobject\base.py:1007, in defaultSerialize(obj, buf, lineLength)
1005 for child in obj.getSortedChildren():
1006 # validate is recursive, we only need to validate once
-> 1007 child.serialize(outbuf, lineLength, validate=False)
1008 if obj.useBegin:

File c:\ProgramData\miniconda3\lib\site-packages\vobject\base.py:254, in VBase.serialize(self, buf, lineLength, validate, behavior)
253 logger.debug("serializing {0!s} with behavior {1!s}".format(self.name, behavior))
--> 254 return behavior.serialize(self, buf, lineLength, validate)
255 else:

File c:\ProgramData\miniconda3\lib\site-packages\vobject\vcard.py:237, in Photo.serialize(cls, obj, buf, lineLength, validate)
236 lineLength = REALLY_LARGE
--> 237 VCardTextBehavior.serialize(obj, buf, lineLength, validate)

File c:\ProgramData\miniconda3\lib\site-packages\vobject\behavior.py:166, in Behavior.serialize(cls, obj, buf, lineLength, validate)
164 undoTransform = False
--> 166 out = base.defaultSerialize(transformed, buf, lineLength)
167 if undoTransform:

File c:\ProgramData\miniconda3\lib\site-packages\vobject\base.py:1015, in defaultSerialize(obj, buf, lineLength)
1014 if obj.behavior and not startedEncoded:
-> 1015 obj.behavior.encode(obj)
1017 s = six.StringIO()

File c:\ProgramData\miniconda3\lib\site-packages\vobject\vcard.py:161, in VCardTextBehavior.encode(cls, line)
160 else:
--> 161 line.value = backslashEscape(line.value)
162 line.encoded = True

File c:\ProgramData\miniconda3\lib\site-packages\vobject\base.py:1219, in backslashEscape(s)
1218 def backslashEscape(s):
-> 1219 s = s.replace("\", "\\").replace(";", ";").replace(",", ",")
1220 return s.replace("\r\n", "\n").replace("\n", "\n").replace("\r", "\n")

TypeError: a bytes-like object is required, not 'str'

During handling of the above exception, another exception occurred:

TypeError Traceback (most recent call last)
Cell In[14], line 8
6 print(f"TypeError: {e}")
7 print("v.serialize() output:")
----> 8 print(v.serialize())

File c:\ProgramData\miniconda3\lib\site-packages\vobject\base.py:254, in VBase.serialize(self, buf, lineLength, validate, behavior)
252 if DEBUG:
253 logger.debug("serializing {0!s} with behavior {1!s}".format(self.name, behavior))
--> 254 return behavior.serialize(self, buf, lineLength, validate)
255 else:
256 if DEBUG:

File c:\ProgramData\miniconda3\lib\site-packages\vobject\behavior.py:166, in Behavior.serialize(cls, obj, buf, lineLength, validate)
163 transformed = obj
164 undoTransform = False
--> 166 out = base.defaultSerialize(transformed, buf, lineLength)
167 if undoTransform:
168 obj.transformToNative()

File c:\ProgramData\miniconda3\lib\site-packages\vobject\base.py:1007, in defaultSerialize(obj, buf, lineLength)
1003 foldOneLine(outbuf, "{0}BEGIN:{1}".format(groupString, obj.name),
1004 lineLength)
1005 for child in obj.getSortedChildren():
1006 # validate is recursive, we only need to validate once
-> 1007 child.serialize(outbuf, lineLength, validate=False)
1008 if obj.useBegin:
1009 foldOneLine(outbuf, "{0}END:{1}".format(groupString, obj.name),
1010 lineLength)

File c:\ProgramData\miniconda3\lib\site-packages\vobject\base.py:254, in VBase.serialize(self, buf, lineLength, validate, behavior)
252 if DEBUG:
253 logger.debug("serializing {0!s} with behavior {1!s}".format(self.name, behavior))
--> 254 return behavior.serialize(self, buf, lineLength, validate)
255 else:
256 if DEBUG:

File c:\ProgramData\miniconda3\lib\site-packages\vobject\vcard.py:237, in Photo.serialize(cls, obj, buf, lineLength, validate)
235 if wacky_apple_photo_serialize:
236 lineLength = REALLY_LARGE
--> 237 VCardTextBehavior.serialize(obj, buf, lineLength, validate)

File c:\ProgramData\miniconda3\lib\site-packages\vobject\behavior.py:166, in Behavior.serialize(cls, obj, buf, lineLength, validate)
163 transformed = obj
164 undoTransform = False
--> 166 out = base.defaultSerialize(transformed, buf, lineLength)
167 if undoTransform:
168 obj.transformToNative()

File c:\ProgramData\miniconda3\lib\site-packages\vobject\base.py:1015, in defaultSerialize(obj, buf, lineLength)
1013 startedEncoded = obj.encoded
1014 if obj.behavior and not startedEncoded:
-> 1015 obj.behavior.encode(obj)
1017 s = six.StringIO()
1019 if obj.group is not None:

File c:\ProgramData\miniconda3\lib\site-packages\vobject\vcard.py:161, in VCardTextBehavior.encode(cls, line)
159 line.value = codecs.encode(line.value.encode(encoding), "base64").decode("utf-8")
160 else:
--> 161 line.value = backslashEscape(line.value)
162 line.encoded = True

File c:\ProgramData\miniconda3\lib\site-packages\vobject\base.py:1219, in backslashEscape(s)
1218 def backslashEscape(s):
-> 1219 s = s.replace("\", "\\").replace(";", ";").replace(",", ",")
1220 return s.replace("\r\n", "\n").replace("\n", "\n").replace("\r", "\n")

TypeError: a bytes-like object is required, not 'str'
vobject.base.ContentLine

[da4089]

Thanks for the report!

It'd be helpful to know:

• the version of Python in use
• the version of vObject in use
• the operating system

and if possible,

• a copy of the vCard the triggers the error
• a short Python program that exhibits the issue

I tried:

import vobject

with open("test_files/vcard_with_groups.ics") as f:
    s = vobject.readOne(f)

c = vobject.readOne(s)
c.serialize().encode("utf-8")
c.serialize().encode("utf-8")
c.serialize().encode("utf-8")

using Python 2.7 and 3.8, but that works fine, so I imagine I'm missing something ...

[aaschmid]

I have the same problem on MacOS, tested with Python 3.10 and 3.12.7. vobject version is 0.9.8. Both is installed via nix.

  File "[...]/main.py", line 291, in _write
    card.serialize(buf=f)
  File "/nix/store/xz4l2h7q23i9azfjqdhwd6q0zsyzyl6n-python3.12-vobject-0.9.8/lib/python3.12/site-packages/vobject/base.py", line 264, in serialize
    return behavior.serialize(self, buf, lineLength, validate, *args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/nix/store/xz4l2h7q23i9azfjqdhwd6q0zsyzyl6n-python3.12-vobject-0.9.8/lib/python3.12/site-packages/vobject/behavior.py", line 167, in serialize
    out = base.defaultSerialize(transformed, buf, lineLength)
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/nix/store/xz4l2h7q23i9azfjqdhwd6q0zsyzyl6n-python3.12-vobject-0.9.8/lib/python3.12/site-packages/vobject/base.py", line 1066, in defaultSerialize
    child.serialize(outbuf, lineLength, validate=False)
  File "/nix/store/xz4l2h7q23i9azfjqdhwd6q0zsyzyl6n-python3.12-vobject-0.9.8/lib/python3.12/site-packages/vobject/base.py", line 264, in serialize
    return behavior.serialize(self, buf, lineLength, validate, *args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/nix/store/xz4l2h7q23i9azfjqdhwd6q0zsyzyl6n-python3.12-vobject-0.9.8/lib/python3.12/site-packages/vobject/behavior.py", line 167, in serialize
    out = base.defaultSerialize(transformed, buf, lineLength)
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/nix/store/xz4l2h7q23i9azfjqdhwd6q0zsyzyl6n-python3.12-vobject-0.9.8/lib/python3.12/site-packages/vobject/base.py", line 1093, in defaultSerialize
    foldOneLine(outbuf, s.getvalue(), lineLength)
  File "/nix/store/xz4l2h7q23i9azfjqdhwd6q0zsyzyl6n-python3.12-vobject-0.9.8/lib/python3.12/site-packages/vobject/base.py", line 1034, in foldOneLine
    outbuf.write(to_unicode(s))
TypeError: a bytes-like object is required, not 'str'

Also haven't looked deeper into it, maybe one of the new cards is broken or something else on my local machine causes the issue ...

[aaschmid]

Debugged my code, and it seems that only two cards were affected. Still couldn't find what the problem is. I am very sure that I created the contacts on my Pixel phone and synced that to my Contact app. But also changing the card in my Contact app manually hasn't solved my issue. Here is the code I use:

my_contacts = _load_contacts(my_contacts_dir, debug)
for path, card in my_contacts.items():
    changed = False
    if "," in card.fn.value:
        changed = True
        split = card.fn.value.split(",")
        card.fn.value = f"{split[1].strip()} {split[0].strip()}"

    if changed:
        if debug:
            print(f"Changed card for {card.getChildValue('fn')} (path: {path}).")
        _write(card, path)

def _write(card: Component, path: Path):
    with path.open("wb") as f:
        card.serialize(buf=f)

This is an anonymized version of the card which I try to adjust:

BEGIN:VCARD
VERSION:3.0
FN:Surname\, Firstname
N:Surname;Firstname;;;
ADR;TYPE=work,postal,parcel:;;Street str. 13\, 12345 City\, Deutschland;;;;
TEL;TYPE=cell,voice:+49 123 456789
REV:2024-12-30T19:08:21Z
UID:4fa3280a-cdd7-4aad-9fa6-bc797b1fff1f:1077539
END:VCARD

Edit: Tested 0.9.9 which also produces the above exception for the exact test card.

[da4089]

Thanks for this info @aaschmid!

I am able to reproduce the issue. For reference, my test case code is below.

import vobject

vobject_0084_card = \
    r"BEGIN:VCARD" "\r\n" \
    r"VERSION:3.0" "\r\n" \
    r"FN:Surname\, Firstname" "\r\n" \
    r"N:Surname;Firstname;;;" "\r\n" \
    r"ADR;TYPE=work,postal,parcel:;;Street str. 13\, 12345 City\, Deutschland;;;;" "\r\n" \
    r"TEL;TYPE=cell,voice:+49 123 456789" "\r\n" \
    r"REV:2024-12-30T19:08:21Z" "\r\n" \
    r"UID:4fa3280a-cdd7-4aad-9fa6-bc797b1fff1f:1077539" "\r\n" \
    r"END:VCARD" "\r\n"


def test_vobject_0084():
    card = vobject.readOne(vobject_0084_card)
    with open("/tmp/vobject_0084_card.txt", "wb") as f:
        card.serialize(buf=f)

[da4089]

This appears to be a symptom of an internal confusion between bytes and string, a consequence of vObject's origins before Python3. There's little clarity or consistency in internal APIs as to whether values should be in encoded or decoded form, and lots of hacky conversions between them if they're not what's expected at any particular point.

I'm working on this, but I expect it'll take a few days to sort it out.

[da4089]

One question: is there a reason you're both opening the output file using the "wb" mode?

If the output stream is opened with the "b" flag, it's a byte stream, and you cannot write string objects to it. This is the immediate cause of the error: serialise() expects to be able to write strings.

A file opened (for writing) with the "w" (not "wb") mode is in text mode, which will accept strings, and use an implicit codec to convert them to UTF-8 on disc.

[aaschmid]

No there is no specific reason to use wb mode. Using w as mode makes it work. Thanks for the quick response and fix.

As this change already fixes the problem, you can close my point of the issue. I just changed my code accordingly :-)

Only strange thing is that it has worked with the above code before, even though I cannot tell which versions of python and vobject I used at the time being...

[da4089]

I haven't checked, but I think Python 2.x would have worked.

[aaschmid]

But it is sunsetted ;-)