Won't read multiple vcards from .vcf file, vobject.readOne(f) only works the first vcard

    #!/usr/bin/env python2.7

    import vobject

    abfile='/foo/bar/directory/file.vcf'

    def test_vobject_dot_readOne():
        with open(abfile) as f:
            vcard = vobject.readOne(f)
            vcard = vobject.readOne(f)

    test_vobject_dot_readOne()

The above code does not work but if we remove one of the two repeated statements it does. I would like to read vcards one by one. Is there a way to do this with vobject.readOne(f)? How can I read vcard n from the file?

The vcf file I'm using is taken from google contacts (exporting as vcard format). Here is the file contents that I have used in the test with only two vcards:

    BEGIN:VCARD 
    VERSION:3.0
    FN:Foo_bar1
    N:;Foo_bar1;;;
    EMAIL;TYPE=INTERNET:foobar1@foo.bar.com
    END:VCARD
    BEGIN:VCARD
    VERSION:3.0
    FN:Foo_bar2 
    N:;Foo_bar2;;;
    EMAIL;TYPE=INTERNET:foobar2@foo.bar.com
    END:VCARD

One can then use the Vcard readings to perform comparisons to avoid duplicates as shown in another question:

To remove vcard contact duplicates, comparing if two vcards are equal in .vcf file does not work with simple == vobject comparison

Solution

Well let's hope I understood correctly what you were trying to do.

Are you trying to do something like this?

#!/usr/bin/env python2.7

import vobject

test_vcard_information = r"""BEGIN:VCARD
VERSION:3.0
FN:Foo_bar1
N:;Foo_bar1;
EMAIL;TYPE=INTERNET:foobar1@foo.bar.com
END:VCARD
BEGIN:VCARD
VERSION:3.0
FN:Foo_bar2
N:;Foo_bar2;
EMAIL;TYPE=INTERNET:foobar2@foo.bar.com
END:VCARD
"""

for vcard in vobject.readComponents(test_vcard_information):
    print vcard.fn.value

Or if you have the information in a file:

#!/usr/bin/env python2.7

import vobject

test_filename = r'/path/to/Test_addressbook.vcf'

with open(test_filename) as source_file:
    for vcard in vobject.readComponents(source_file):
       print vcard.fn.value

You would probably use .readOne() with a calendar file (.ics) since it would be composed of a single root object like in this example:

#!/usr/bin/env python2.7

import vobject

test_calendar_information = r"""BEGIN:VCALENDAR
PRODID:-//Mozilla.org/NONSGML Mozilla Calendar V1.1//EN
VERSION:2.0
BEGIN:VTIMEZONE
TZID:America/Toronto
BEGIN:DAYLIGHT
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
TZNAME:EDT
DTSTART:19700308T020000
RRULE:FREQ=YEARLY;BYDAY=2SU;BYMONTH=3
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
TZNAME:EST
DTSTART:19701101T020000
RRULE:FREQ=YEARLY;BYDAY=1SU;BYMONTH=11
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
CREATED:20170104T022518Z
LAST-MODIFIED:20170104T022643Z
DTSTAMP:20170104T022643Z
UID:3fab09d6-59bb-430b-8b21-56c9636871e2
SUMMARY:Write a chapter
CATEGORIES:Projects
DTSTART;TZID=America/Toronto:20170105T140000
DTEND;TZID=America/Toronto:20170105T150000
TRANSP:OPAQUE
X-MOZ-GENERATION:2
LOCATION:At home
DESCRIPTION:One day I will be a great writer but I have to start somewhere...
SEQUENCE:1
END:VEVENT
BEGIN:VEVENT
CREATED:20170104T022346Z
LAST-MODIFIED:20170104T022654Z
DTSTAMP:20170104T022654Z
UID:b304f46a-f533-4aa4-8ee1-3b59649dedfa
SUMMARY:See a movie
CATEGORIES:Entertainment
DTSTART;TZID=America/Toronto:20170103T110000
DTEND;TZID=America/Toronto:20170103T140000
TRANSP:OPAQUE
X-MOZ-GENERATION:4
LOCATION:Somewhere over the rainbow
DESCRIPTION:The Wizard of Oz is movie I haven't seen in a long time.\n\nWe
  should schedule a time to see it
SEQUENCE:1
END:VEVENT
END:VCALENDAR"""

vcalendar = vobject.readOne(test_calendar_information)
for vevent in vcalendar.vevent_list:
    print vevent.summary.value

Or if it is in a file:

#!/usr/bin/env python2.7

import vobject

test_filename = r'/path/to/Test_Calendar.ics'

with open(test_filename) as source_file:
    vcalendar = vobject.readOne(source_file)
    for vevent in vcalendar.vevent_list:
        print vevent.summary.value