dateformat 0.9.7
Parse and format dates quickly
License: MIT

        
        `dateformat` does two things:  turn `datetime` objects into strings, and turn strings into `datetime` objects.
        It's goal is to do these things simply and well, and to satisfy the following criteria:
        
         * Be fast enough (see below for benchmarks)
         * Handle a variety of date formats from multiple sources
         * Parse and format dates in many timezones and with many timezone offsets
         * Represent the expected format in a way that a non-technical person may understand
         * Be explicit about the expected format to prevent heuristic errors
        
        > "But why another date library?"
        
        There isn't currently a python library I've been able to find that matches these 
        requirements well enough for my use-cases.  [`Arrow`](http://arrow.readthedocs.io/en/latest/)
         comes closest, but still isn't quite suitable performance-wise.
        
        # Usage
        
        All functionality is based around DateFormat() objects:
        
        ### `def __init__(self, spec, is_24hour=None)`
        
        create a dateformat object from the provided spec string.
        
        ```
        >>> from dateformat import DateFormat
        
        >>> date_format = DateFormat("YYYY-MM-DD hh:mm:ss.SSSS+HH:MM")
        ```
        
        If `is_24hour` is not provided, the format will be in 12-hour mode if an am/pm 
        part is present in the spec, otherwise, dates will be in 24-hour mode.
        
        DateFormat instances have two methods:
        
        ### `def parse(self, data)`
        
        Parse a string(`data`) containing a date into a datetime object.
        
        ```
        >>> date = date_format.parse("2017-06-03 15:32:00.2364-02:00")
        datetime.datetime(2017, 6, 3, 15, 32, 0, 236400, tzinfo=datetime.timezone(datetime.timedelta(-1, 79200)))
        ```
        
        ### `def format(self, date)`
        
        Format the passed in `datetime.datetime` object (`date`) as a string:
        
        ```
        >>> print(date_format.format(date))
        2017-06-03 15:32:00.2364-02:00
        ```
        
        ## Timezones
        
        If any part of the format provides a timezone, or UTC offset, then parsing 
        produces dates with a timezone indicating the relevant UTC offset.
        
        Likewise, if a dateformat has a timezone part, then dates passed to `.format()`
        must include a tzinfo value.
        
        If pytz is available, then some level of named timezone support is provided.
        
        ## Leading zeros
        
        All numeric parts of the date format are zero-padded to the number of characters
        in the spec.  I.e.  'DD' means that the day of the month is zero-padded to 2-digits.
        
        During parsing, a missing leading zero is usually ignored, but if there is no separator
        between parts (for example:  YYYYMMDD), then a missing leading zero will cause an error or bad value.
        
        Currently, all formatted dates are zero-padded, in the future, this may be controllable.
        
        ## Date format specification
        | Part | Example | Description |
        |---------|---------|---------------|
        | `+HHMM` | -0515 | A UTC offset provided as a 2-digit hour, and 2-digit minute, with no separator |
        | `+HH:MM` | -05:15 | A UTC offset provided as a 2-digit hour, and 2-digit minute, with a ':' separator |
        | `+HH` | -05 | A UTC offset provided as a 2-digit hour only |
        | `Dddddd` | Monday | The full locale-specific day of the week (Note, this value is ignored during date parsing, but added during date format) |
        | `Ddd` | Mon | The locale-specific short name for the day of the week (Ignored during parsing) |
        | `DD` | 05 | The zero-padded day of the month. |
        | `MMMMM` | September | Month as locale’s full name |
        | `MMM` | Sep | Month as locale’s abbreviated name |
        | `YYYY` | 2017 | Year with century as a number |
        | `YY` | 17 | Year without century as a zero-padded number |
        | `hh` | 09 | Hour as a zero-padded number |
        | `mm` | 06 | Minute as a zero-padded number |
        | `ss` | 45 | Second as a zero-padded number |
        | `SSSSSS` | 123456 | Microsecond as a zero-padded decimal number |
        | `SSSS`   | 1234 | 100-microseconds as a zero-padded number |
        | `SSS` | 123 | milliseconds as a zero-padded number |
        | `SS` | 12 | 10-milliseconds as a zero-padded number |
        | `am` `Am` `AM` `pm` `Pm` `PM` | am | either AM or PM depending on the hour.  `.format()` matches the case of the spec.  If present, the dateformat will default to 12-hour mode |
        | `of` | | Ignored during parsing, added during formtting |
        | `st` | th | The appropriate suffix for the day of the month, for example '1_st_ July', '2_nd_ March' |
        | `␣` | T | (Unicode OPEN BOX - U+2423) Matches either the character 'T' or a space ' '.  During formatting, 'T' is always used (this is provided to improve flexibility when parsing iso8601 formats) |
        | space | | Matches one or more spaces during parsing.  During formatting, one space will be output |
        | any of `:/-.,TZ()` | | Ignored during parsing, output as-is during formatting |
        
        
        # Examples
        
        | Format                   | Example                |
        |--------------------------|------------------------|
        | `YYYY-MM-DDThh:mm:ss`    | 2017-06-06T09:45:15    |
        | `YYYYMMDDhhmmss`         | 20170606094515         |
        | `YYYYMMDDhhmmss.SSSSSSZ` | 20170606094515.123456Z |
        | `MM/DD/YY hh:mm+HHMM`    | 06/06/17 09:45-0500    |
        
        
        # Library comparison
        
        ## dateformat ⇄ datetime (builtin python module)
        
        Dateformat is *not* trying to be a replacement for the builtin datetime module.  `datetime.datetime` objects are used as the input/output to the parsing and formatting methods.
        
        It is designed as a replacement for the  `datetime.datetime.strftime` and `datetime.datetime.strptime` methods, providing:
        
         * better timezone handling
         * a simpler/more common syntax for specifying the date formats
         * slightly faster parsing
        
        ## dateformat ⇄ dateutil.parser.parse()
        
        `dateutil.parser.parse`'s intent is to turn a string in an unknown format into a date.  It does that by using a variety of heuristics to try to figure out the format the date has been expressed in.
        
        This approach is highly useful, and very flexible, but suffers from a couple of drawbacks that dateformat doesn't have:
        
         * There is ambiguity about what date will be produced from a given string, there are situations where that risk cannot be accepted, and it's important for the system to only accept a certain date format
         * Because of all the work that dateutil is doing to work out the format used, it's fairly slow, at just under 10x slower than `strptime`, this is very noticable over 10s - 100s thousands of dates.
        
        ## dateformat ⇄ arrow
        
        arrow is the closest to the way dateformat works, the syntax for describing dates is very similar. Unfortunately, arrow constructs its parser every time a date is parsed, creating a significant overhead when parsing each date.
        
        ## dateformat ⇄ iso8601 / ciso8601
        
        ciso8601 is _really_ fast.  Unfortunately both these libraries only handle a single date format, so are not useful in this situation.
        
        # Benchmarks
        
        the `benchmark/` dir contains some simple scripts to show how the relative libraries perform at parsing and formatting dates.
        
        Running on a 2016 macbook pro, on Python 3.6.3 gave the following results (best of 3 runs):
        
        (Please note, the parse time chart y-axis has been clamped to 1s, but dateparser took 16s to complete)
        
        ![chart showing relative date parse performance](https://github.com/stestagg/dateformat/raw/master/benchmark/parse_times.png)
        
        ![chart showing relative date format performance](https://github.com/stestagg/dateformat/raw/master/benchmark/format_times.png)
        
        
Keywords: date time parsing formatting datetime
Platform: UNKNOWN
Classifier: Development Status :: 3 - Alpha
Classifier: Intended Audience :: Developers
Classifier: Topic :: Software Development :: Build Tools
Classifier: License :: OSI Approved :: MIT License
Classifier: Programming Language :: Python :: 3
Classifier: Programming Language :: Python :: 3.3
Classifier: Programming Language :: Python :: 3.4
Classifier: Programming Language :: Python :: 3.5
Provides-Extra: test