Mark Fowler > Test-Recent > Test::Recent

Download:
Test-Recent-2.50.tar.gz

Dependencies

Annotate this POD

Website

View/Report Bugs
Module Version: 2.50   Source  

NAME ^

Test::Recent - check a time is recent

SYNOPSIS ^

   use Test::More;
   use Test::Recent qw(recent);

   # check things happened in the last ten seconds
   recent DateTime->now, "now is recent!";
   recent "2012-12-23 00:00:00", "end of mayan calendar happened recently?";

   # check things happened in the last hour
   recent "2012-12-23 00:00:00", DateTime::Duration->new( hours => 1 ), "mayan";
   recent "2012-12-23 00:00:00", "1 hour", "mayan"

DESCRIPTION ^

Simple module to check things happened recently.

Functions

These are exported on demand or may be called fully qualified

recent $date_and_time
recent $date_and_time, $test_description
recent $date_and_time, $duration, $test_description

Tests (using the Test::Builder framework) if the time occurred within the duration ago from the current time. If no duration is passed, ten seconds is assumed.

occured_within_ago $date_and_time, $duration

Returns true if and only if the time occurred within the duration ago from the current time.

Parsing of DateTimes

This module supports the following things being passed in as a date and time:

epoch seconds
A DateTime object
An ISO8601 formatted date string

i.e. anything that DateTime::Format::ISO8601 can parse

A Postgres style TIMESTAMP WITH TIME ZONE

i.e. something of the form YYYY-MM-DD HH:MM:SS.ssssss+TZ

Older versions of this module used DateTimeX::Easy to parse the datetime, but this proved to be unreliable.

Future Timestamps

By default Test::Recent fails any timestamp that comes from the future as not being recent, which is sensible behavior if you expect the timestamps to be generated on the same machine as you're running the test on.

However, there are several situations where this might not be what you want.

Remote Machines

If your network is faster than the clock drift between the machine you're running the test on and the machine (e.g. the database server) that's creating the timestamp then you might get future timestamps.

Rounding Errors

Some situations can result in creating a timestamp from the future due to rounding errors. For example executing this on postgresql:

  SELECT EXTRACT(epoch FROM current_timestamp)::integer;

Will give you a timestamp in the future 50% of the time.

There's two things you can do:

Pass an arrayref instead

Instead of passing just a single duration, you can pass an arrayref containing two durations:

   recent $datetime, [ 10, 5 ], "is within 10 sec ago, or 5 secs from now";
   recent $datatime, [
      DateTime::Duration->new( seconds => 10 ),
      DateTime::Duration->new( seconds => 5 ),
   ],  "is within 10 sec ago, or 5 secs from now";

   occured_within_ago $datetime, [ 10, 5 ] or die "boom!";
   occured_within_ago $datatime, [
      DateTime::Duration->new( seconds => 10 ),
      DateTime::Duration->new( seconds => 5 ),
   ] or die "boom";
Set the global variable

You can set a global variable that will always allow so much into the future:

  local $Test::Recent::future_duration = 5;
  recent $datetime, 10, "is within 10 sec ago, or 5 secs from now";

  local $Test::Recent::future_duration =
     DateTime::Duration->new( seconds => 5 );
  recent $datetime, 10, "is within 10 sec ago, or 5 secs from now";

Overriding the sense of "now"

Sometimes you want someone else's concept of now. For example, you might want to pull back the time from the database server and compare against that rather than your own local clock.

This can be done by setting the $Test::Recent::RelativeTo variable. For safety's sake, this should probably be done with local:

    {
        local $Test::Recent::RelativeTo =
            $dbh->selectcol_arrayref("SELECT NOW()")->[0];
        recent($time);
    }

You can set $Test::Recent::RelativeTo to anything that Test::Recent can parse.

AUTHOR ^

Written by Mark Fowler <mark@twoshortplanks.com>

COPYRIGHT ^

Copyright OmniTI 2012. All Rights Reserved. Copyright Circonus 2014. All Rights Reserved.

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

BUGS ^

This module ignores sub-seconds. This is primarily because the current implementation of DateTime's now method does not return nanoseconds, meaning that technically now returns a time that is in the past and might occur before a timestamp you hand in that contained nanoseconds (and therefore would erroneously be not concidered "recent")

Bugs should be reported via this distribution's CPAN RT queue. This can be found at https://rt.cpan.org/Dist/Display.html?Test-Recent

You can also address issues by forking this distribution on github and sending pull requests. It can be found at http://github.com/2shortplanks/Test-Recent

In order not to depend on another DateTime library, this module converts postgres style TIMESTAMP WITH TIME ZONE by using a regular expression and simply ignoring microseconds. This potentially introduces a one second inaccuracy in the recent handling.

SEE ALSO ^

DateTime::Format::ISO8601, Time::Duration::Parse

syntax highlighting: