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PyPI · #1457 most downloaded on PyPI
RFC 5545 compatible parser and generator of iCalendar files
Last release 29 days ago
19 Aug 2026
Release timing varies
gaps range from 2 weeks to 5 months
Nearly every release is documented
notes for 59 of the last 60 stable releases
Nothing withdrawn
no release was ever pulled
20 years old
90 releases · first in 2006
Run tests with python 3.5 and 3.6. [geier]
Run tests with python 3.5 and 3.6. [geier]
Allow tests failing with pypy3 on travis.ci. [geier]
Encode error message before adding it to the stack of collected error messages.
Encode error message before adding it to the stack of collected error messages.
One column per quarter.
Successfully test with pypy and pypy3. [gforcada]
Fixes:
Successfully test with pypy and pypy3. [gforcada]
Minor documentation update. [tpltnt]
Updated components description to better comply with RFC 5545. Refs #183. [stlaz]
New:
Updated components description to better comply with RFC 5545. Refs #183. [stlaz]
Added PERIOD value type to date types. Also fixes incompatibilities described in #184. Refs #189. [stlaz]
Fixes:
Fix testsuite for use with dateutil>=2.5. Refs #195. [untitaker]
Reintroduce cal.Component.is_broken that was removed with 3.9.2. Refs #185. [geier]
Defined test_suite in setup.py. Now tests can be run via python setup.py test. [geier]
New:
Defined test_suite in setup.py. Now tests can be run via python setup.py test. [geier]
Fixes:
Fixed cal.Component.from_ical() representing an unknown component as one of the known. [stlaz]
Fixed possible IndexError exception during parsing of an ical string. [stlaz]
When doing a boolean test on icalendar.cal.Component, always return True. Before it was returning False due to CaselessDict, if it didn't contain any items. [stlaz]
Fixed date-time being recognized as date or time during parsing. Added better error handling to parsing from ical strings. [stlaz]
Added __version__ attribute to init.py. [TomTry]
Documentation fixes. [TomTry]
Pep 8, UTF 8 headers, dict/list calls to literals. [thet]
Fix vPeriod.__repr__. [spacekpe]
Fix vPeriod.__repr__. [spacekpe]
Improve foldline() performance. This improves the foldline performance, especially for large strings like base64-encoded inline attachements. In some cases (1MB string) from 7 Minutes to less than 20ms for ASCII data and 500ms for non-ASCII data. Ref: #163. [emfree]
Creating timezone objects from VTIMEZONE components. [geier]
Creating timezone objects from VTIMEZONE components. [geier]
Make python-dateutil a dependency. [geier]
Made RRULE tolerant of trailing semicolons. [sleeper]
Documentation fixes. [t-8ch, thet]
Add missing BYWEEKNO to recurrence rules. [russkel]
Add missing BYWEEKNO to recurrence rules. [russkel]
PERCENT property in VTODO renamed to PERCENT-COMPLETE, according to RFC5545. [thomascube]
PERCENT property in VTODO renamed to PERCENT-COMPLETE, according to RFC5545. [thomascube]
Exclude editor backup files from egg distributions. Fixes #144. [thet]
Exclude editor backup files from egg distributions. Fixes #144. [thet]
The representation of CaselessDicts in 3.8 changed the name attribute of Components and therefore broke the external API. This has been fixed. [untita
The representation of CaselessDicts in 3.8 changed the name attribute of Components and therefore broke the external API. This has been fixed. [untitaker]
Allow dots in property names (Needed for vCard compatibility). Refs #143. [untitaker]
Allow dots in property names (Needed for vCard compatibility). Refs #143. [untitaker]
Change class representation for CaselessDict objects to always include the class name or the class' name attribute, if available. Also show subcomponents for Component objects. [thet]
Don't use data_encode for CaselessDict class representation but use dict's __repr__ method. [t-8ch]
Handle parameters with multiple values, which is needed for vCard 3.0. Refs #142. [t-8ch]
For components with ignore_exceptions set to True, mark unparseable lines as broken instead rising a ValueError. VEVENT components have ignore_excepti
For components with ignore_exceptions set to True, mark unparseable lines as broken instead rising a ValueError. VEVENT components have ignore_exceptions set to True by default. Ref #131. Fixes #104. [jkiang13]
Make python-dateutil a soft-dependency. [boltnev]
Add optional sorted parameter to Component.to_ical. Setting it to false allows the user to preserve the original property and parameter order. Ref #136. Fixes #133. [untitaker]
Fix tests for latest pytz. Don't set tzinfo directly on datetime objects, but use pytz's localize function. Ref #138. [untitaker, thet]
Remove incorrect use of __all__. We don't encourage using from package import * imports. Fixes #129. [eric-wieser]
- Pep8 and cleanup. [lasudry]
Pep8 and cleanup. [lasudry]
Open text files referenced by setup.py as utf-8, no matter what the locale settings are set to. Fixes #122. [sochotnicky]
Open text files referenced by setup.py as utf-8, no matter what the locale settings are set to. Fixes #122. [sochotnicky]
Add tox.ini to source tarball, which simplifies testing for in distributions. [sochotnicky]
Python3 (3.3+) + Python 2 (2.6+) support [geier]
Python3 (3.3+) + Python 2 (2.6+) support [geier]
Made sure to_ical() always returns bytes [geier]
Support adding lists to a component property, which value already was a list and remove the Component.set method, which was only used by the add method. [thet]
Remove ability to add property parameters via a value's params attribute when adding via cal.add (that was only possible for custom value objects and makes up a strange API), but support a parameter attribute on cal.add's method signature to pass a dictionary with property parameter key/value pairs. Fixes #116. [thet]
Backport some of Regebro's changes from his regebro-refactor branch. [thet]
Raise explicit error on another malformed content line case. [hajdbo]
Correctly parse datetime component property values with timezone information when parsed from ical strings. [untitaker]
Let to_unicode be more graceful for non-unicode strings, as like CMFPlone's safe_unicode does it. [thet]
Let to_unicode be more graceful for non-unicode strings, as like CMFPlone's safe_unicode does it. [thet]
Switch to unicode internally. This should fix all en/decoding errors. [thet]
Switch to unicode internally. This should fix all en/decoding errors. [thet]
Support for non-ascii parameter values. Fixes #88. [warvariuc]
Added functions to transform chars in string with '\' + any of r',;:' chars into '%{:02X}' form to avoid splitting on chars escaped with '\'. [warvariuc]
Allow seconds in vUTCOffset properties. Fixes #55. [thet]
Let Component.decode better handle vRecur and vDDDLists properties. Fixes #70. [thet]
Don't let Component.add re-encode already encoded values. This simplifies the API, since there is no need explicitly pass encode=False. Fixes #82. [thet]
Rename tzinfo_from_dt to tzid_from_dt, which is what it does. [thet]
More support for dateutil parsed tzinfo objects. Fixes #89. [leo-naeka]
Remove python-dateutil version fix at all. Current python-dateutil has Py3 and Py2 compatibility. [thet]
Declare the required python-dateutil dependency in setup.py. Fixes #90. [kleink]
Raise test coverage. [thet]
Remove interfaces module, as it is unused. [thet]
Remove test_doctests.py, test suite already created properly in test_icalendar.py. [rnix]
Transformed doctests into unittests, Test fixes and cleanup. [warvariuc]
Drop support for Python < 2.6. [thet]
Drop support for Python < 2.6. [thet]
Allow vGeo to be instantiated with list and not only tuples of geo coordinates. Fixes #83. [thet]
Don't force to pass a list to vDDDLists and allow setting individual RDATE and EXDATE values without having to wrap them in a list. [thet]
Fix encoding function to allow setting RDATE and EXDATE values and not to have bypass encoding with an icalendar property. [thet]
Allow setting of timezone for vDDDLists and support timezone properties for RDATE and EXDATE component properties. [thet]
Move setting of TZID properties to vDDDTypes, where it belongs to. [thet]
Use @staticmethod decorator instead of wrapper function. [warvariuc, thet]
Extend quoting of parameter values to all of those characters: ",;: â'". This fixes an outlook incompatibility with some characters. Fixes: #79, Fixes: #81. [warvariuc]
Define VTIMETZONE subcomponents STANDARD and DAYLIGHT for RFC5545 compliance. [thet]
Documentation file layout restructuring. [thet]
Documentation file layout restructuring. [thet]
Fix time support. vTime events can be instantiated with a datetime.time object, and do not inherit from datetime.time itself. [rdunklau]
Correctly handle tzinfo objects parsed with dateutil. Fixes #77. [warvariuc, thet]
Text values are escaped correclty. Fixes #74. [warvariuc]
Returned old folding algorithm, as the current implementation fails in some cases. Fixes #72, Fixes #73. [warvariuc]
Supports to_ical() on date/time properties for dates prior to 1900. [cdevienne]
Make sure parameters to certain properties propagate to the ical output. [kanarip]
Make sure parameters to certain properties propagate to the ical output. [kanarip]
Re-include doctests. [rnix]
Ensure correct datatype at instance creation time in prop.vCalAddress and prop.vText. [rnix]
Apply TZID parameter to datetimes parsed from RECURRENCE-ID [dbstovall]
Localize datetimes for timezones to avoid DST transition errors. [dbstovall]
Allow UTC-OFFSET property value data types in seconds, which follows RFC5545 specification. [nikolaeff]
Remove utctz and normalized_timezone methods to simplify the codebase. The methods were too tiny to be useful and just used at one place. [thet]
When using Component.add() to add icalendar properties, force a value conversion to UTC for CREATED, DTSTART and LAST-MODIFIED. The RFC expects UTC for those properties. [thet]
Removed last occurrences of old API (from_string). [Rembane]
Add 'recursive' argument to property_items() to switch recursive listing. For example when parsing a text/calendar text including multiple components (e.g. a VCALENDAR with 5 VEVENT``s), the previous situation required us to look over all properties in ``VEVENT``s even if we just want the properties under the ``VCALENDAR component (VERSION, PRODID, CALSCALE, METHOD). [dmikurube]
All unit tests fixed. [mikaelfrykholm]
For all TZID parameters in DATE-TIME properties, use timezone identifiers (e.g. Europe/Vienna) instead of timezone names (e.g. CET), as required by RF
For all TZID parameters in DATE-TIME properties, use timezone identifiers (e.g. Europe/Vienna) instead of timezone names (e.g. CET), as required by RFC5545. Timezone names are used together with timezone identifiers in the Timezone components. [thet]
Timezone parsing, issues and test fixes. [mikaelfrykholm, garbas, tgecho]
Since we use pytz for timezones, also use UTC tzinfo object from the pytz library instead of own implementation. [thet]
Update Release information. [thet]
Update Release information. [thet]
Add API for proper Timezone support. Allow creating ical DATE-TIME strings with timezone information from Python datetimes with pytz based timezone in
Add API for proper Timezone support. Allow creating ical DATE-TIME strings with timezone information from Python datetimes with pytz based timezone information and vice versa. [thet]
Unify API to only use to_ical and from_ical and remove string casting as a requirement for Python 3 compatibility: New: to_ical. Old: ical, string, as_string and string casting via __str__ and str. New: from_ical. Old: from_string. [thet]
migration to https://github.com/collective/icalendar using svn2git preserving tags, branches and authors. [garbas]
migration to https://github.com/collective/icalendar using svn2git preserving tags, branches and authors. [garbas]
using tox for testing on python 2.4, 2.5, 2.6, 2.6. [garbas]
fixed tests so they pass also under python 2.7. [garbas]
running tests on https://jenkins.plone.org/job/icalendar (only 2.6 for now) with some other metrics (pylint, clonedigger, coverage). [garbas]
review and merge changes from https://github.com/cozi/icalendar fork. [garbas]
created sphinx documentation and started documenting development and goals. [garbas]
hook out github repository to https://about.readthedocs.com service so sphinx documentation is generated on each commit (for main). Documentation can be visible on: https://icalendar.readthedocs.io/en/latest/ [garbas]
Fix deprecation warnings about object.__init__ taking no parameters.
Fix deprecation warnings about object.__init__ taking no parameters.
Set the VALUE parameter correctly for date values.
Long binary data would be base64 encoded with newlines, which made the iCalendar files incorrect. (This still needs testing).
Correctly handle content lines which include newlines.
Made the tests run under Python 2.5+
Made the tests run under Python 2.5+
Renamed the UTC class to Utc, so it would not clash with the UTC object, since that rendered the UTC object unpicklable.
EXDATE and RDATE now returns a vDDDLists object, which contains a list of vDDDTypes objects. This is do that EXDATE and RDATE can contain lists of dat
EXDATE and RDATE now returns a vDDDLists object, which contains a list of vDDDTypes objects. This is do that EXDATE and RDATE can contain lists of dates, as per RFC.
*Note!*: This change is incompatible with earlier behavior, so if you handle EXDATE and RDATE you will need to update your code.
When createing a vDuration of -5 hours (which in itself is nonsensical), the ical output of that was -P1DT19H, which is correct, but ugly. Now it's '-PT5H', which is prettier.
Fixed a string index out of range error in the new folding code.
Fixed a string index out of range error in the new folding code.
Fixed a bug in caselessdicts popitem. (thanks to Michael Smith )
Fixed a bug in caselessdicts popitem. (thanks to Michael Smith <msmith@fluendo.com>)
The RFC 2445 was a bit unclear on how to handle line folding when it happened to be in the middle of a UTF-8 character. This has been clarified in the following discussion: [Ietf-calsify] draft-ietf-calsify-rfc2445bis-01.txt / UTF-8. And this is now implemented in iCalendar. It will not fold in the middle of a UTF-8 character, but may fold in the middle of a UTF-8 composing character sequence.
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