[erlang-questions] [ANN] qdate - Unified Date Formatting/Parsing and Timezone Management

Jesse Gumm <>
Tue Apr 30 07:09:50 CEST 2013


Hello Erlangers,

I'm proud to announce the beta release (v0.1.0) of "qdate" - a unified date
parsing/formatting and timezone management utility for Erlang.

Blog post describing my thoughts that went into its development
http://sigma-star.com/blog/post/qdate

Source code on GitHub (includes a README that covers all the functionality)
https://github.com/choptastic/qdate


At its core, qdate is basically a wrapper around ec_date (fork of dh_date
and part of erlware_commons) and erlang_localtime.

But it's much more than just a wrapper. It's the complete date and time
utility I feel is greatly needed in the Erlang world (since I found myself
needing it).

Briefly, here's what it does:

* Easily convert from any date format to any other date format: datetime(),
now(), unix timestamp, and formatted date strings (list and binaries) are
all acceptable:
    > qdate:to_string("Y-m-d g:ia", Date).
    "2012-12-21 5:51pm"
    > qdate:to_string(<<"Y-m-d g:ia">>, Date).
    <<"2012-12-21 5:51pm">>
    > qdate:to_unixtime(Date).
    1356112260
    > qdate:to_date(Date).
    {{2012,12,21},{17,51,0}}
    > qdate:to_now(Date).
    {1356,112260,0}
    % Note, that the argument `Date` can be anything
    % that's a Date/Time Format (datetime Tuple, now tuple,
    % Integer (unixtime), or string ("2012-12-21 5:51pm")

* Extends ec_date's formatting functions to include PHP's timezone-related
characters:
   > qdate:to_string("Y-m-d g:ia T", Date)
   "2012-12-21 5:51pm CST"

* Able to pre-parse timezones from text strings, and convert from one
timezone to another:
  % Read Timezone from string, convert to datetime in EST
   > qdate:to_date("2012-12-21 5:51pm CST","EST").
   {{2012,12,21},{18,51,0}}
   % Read timezone from string, convert to a string in EST
   > qdate:to_string("n/j/Y g:ia T","2012-12-21 5:51pm CST", "EST").
   "12/21/2012 6:51pm EST"

* Register timezones with the qdate server by a key (to make a timezone
alias) or by pid():
   %% Set timezone for the current process to GMT
   > qdate:set_timezone("GMT").
   %% Set timezone for some_key to HKT
   > qdate:set_timezone(some_key, "HKT").

* Register custom formatting strings with the qdate server, for quick
reference.
    > qdate:register_format(long_date, "l, F jS, Y g:i A T").
    ok
    > qdate:to_string(long_date,1356133860).
    "Friday, December 21st, 2012 11:51 PM GMT"

* Register custom parsing functions with the qdate server, to be
transparently used for conversion.
      > qdate:register_parser(weird_format, fun parse_esoteric_format/1).
     ok
     > qdate:to_date("20121221.115100").
     {{2012,12,21},{11,51,00}}

* Attempt to maintain API compatibility with ec_date by supporting
qdate:parse, qdate:nparse, and qdate:format.


I hope some of you find this useful in your apps.

Any issues, comments, complaints, bug reports, whatever, feel free to post
in this thread, make a github issue, shoot me a message on twitter
(@jessegumm) or email me directly.

Thanks, and I hope everyone has a glorious day or evening or whatever
timezone you happen to be in.

-- 
Jesse Gumm
Owner, Sigma Star Systems
414.940.4866 || sigma-star.com || @jessegumm
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://erlang.org/pipermail/erlang-questions/attachments/20130430/3b7339d4/attachment.html>


More information about the erlang-questions mailing list