Changes

Version 1.45 - 15th April 2007
    + Added "allow_empty_sources" parameter to the new()
      constructor method.

    + Added support to pass in a printf format to the
      extended_legend parameter in the graph() method.


Version 1.44 - 24th Janurary 2008
    + Fixed some small typos in the POD.

    + Added "on_missing_ds" parameter to the new()
      constructor method to detemine what action should
      be taken when the user tries to update or insert
      new data point values in an RRD for a data source
      name that does not exist.

    + Added "tmpdir" parameter to the new() constructor
      method to force any temporary files to be created
      in the specified directory. This is only used in
      the add_source() / _modify_source code.

    + Added a number of additional TRACE() statements
      in the code to aid debugging with the DEBUG=1
      environment variable.

    + Changed graph() so that there is no longer an
      AVERAGE VDEF vname generated for each data source
      by default. See the updated example on drawing
      average lines in RRD::Simple::Examples.

    + Changed graph() method to allow undef or ''
      (empty) values to be passed in for the sources
      parameter. This is useful if you do not want to
      draw and data source values directly on the graph
      but instead only want to plot CDEF values. As a
      result and requirement of this change, the DEF
      statements for each and every data source in the
      RRD file are always defined early on in the
      commands passed on to RRDs.pm.

    + Added a new example to RRD::Simple::Examples
      to show how to generate predictive graphs to
      provide basic capacity planning. See
      examples/mem_usage-monthly.png for the example
      output.

    + Added a new "periods" parameter to the graph()
      method to restrict which graphs will be
      generated. For example, "weekly, month" could
      be specified to only generate those two graphs.
      This is useful if you want to use the SHIFT
      command to produce a capacity planning graph
      based on the last 6 months projecting in to the
      next 6 months in an annual graphing period.

    + Updated version of rrd.me.uk in the examples
      sub-directory of this distribution, inside the
      "rrd-server" directory.


Version 1.43 - 5th March 2007
    + Changed Build.PL to be more paranoid defaulting
      to no while using $build->y_n to work around
      potential removal of expected method functionality.

    + Added complain.txt. 

    + Added instructions for installing rrdtool and RRDs
      under Debian/Ubuntu, RHEL and Fedora Core to the
      INSTALL file.

    + Various fixes and improvements to the POD.

    + Added another example to RRD::Simple::Examples.

    + Fixed typos in existing examples 1 to 5 in
      RRD::Simple::Examples.


Version 1.42 - 27th February 2007
    + Increased the spacing on the graph between the
      timestamps in the bottom right hand corner and
      the legend if the "extended-legend" parameter is
      NOT specified.

    + Added the "file" parameter to the new() constructor
      method to specify the RRD filename to be used for
      by the resulting RRD::Simple object. Eventually
      this will replace the (now optional) ability to
      pass the RRD filename as the first parameter to
      subsequent object methods.

    + Changed the POD to reflect the above changes
      to the new() constructor method regarding passing
      of the RRD filename at object creation time.

    + Added new unit text for the above changes
      to the new() constructor method.

    + Corrected minimum RRD::Simple version for
      rrd-server.pl as documented in README.

    + Updated the main POD to include data resolution
      information for each of the 6 different data
      retention period schemes.

    + Changed to an inside out object. Use the DEBUG
      environment variable to debug.

    + Updated and renamed RRD::Simple::Examples from
      a .pm file to a .pod file since it contains no
      actual code (only documentation).


Version 1.41 - 11th February 2007
    + Added RRD::Simple::Examples POD.

    + Added new requirement of POSIX to Build.PL.

    + Added new timestamp parameter to the graph()
      method.

    + Added heartbeat() method and POD and unit
      test for it.

    + Documented some parameters to the new()
      constructor method that were previously
      undocumented.

    + Updated version of examples/data_gathering/*
      scripts, as currently used on http://rrd.me.uk


Version 1.40 - 24th August 2006
    + Some small changes to POD.

    + Updated version of examples/data_gathering/*
      scripts, as currently used on http://rrd.me.uk

    + Changed RRDs::error calls to RRDs::error().

    + Changed debug warn() calls to carp().

    + Explicitly import fewer symbols from other
      modules.

    + Added rename_source() method and associated
      POD and unit test.

    + Changed the graph() method to recognise use
      of command (GPRINT,PRINT,COMMENT,VRULE,.. etc)
      over options and flags, so that they will be
      added to the graph definition after the
      data sources have been defined.

    + Added new unit tests for new functionality.
      t/35average_hrule.t tests and demonstrates
      how the changes to the graph() method can be
      used.

    + Fixed a bug where an uninitialised variable
      could cause unexpected behaviour if you tried
      to add a new data source using add_source()
      method. This only manifested itself with an
      versions of RRDs earlier than 1.2013, and
      where the rrdtool binary is not installed or
      the path to the rrdtool binary is unknown.


Version 1.39 - 26th June 2006
    + Changed the return value from the graph()
      method to be a hash instead of an array, so
      that the data inside can be easily identified
      as being generated by a specific graph (daily,
      weekly, monthly, annual or 3year).

    + Added the min, max and last values plotted in
      each graph, and the filename of the image file
      written to disk to the graph() method return
      value.

    + Added some more checks in unit tests t/23graph.t
      and t/21synopsis.t to account for the changed
      to the graph() method return value.

    + Updated POD to reflect change in the return
      value from the graph() method.

    + Fixed an uninitialised value warning that
      occured if the graph() method was passed too
      few items in the 'sources' paramater compared
      to the number of items passed in the
      'source_drawtypes' or 'source_labels'
      paramaters.

    + Added client/server server monitoring scripts
      in examples/data_gathering.

    + Updated POD for update() method to make it
      clearer that updating an RRD file that does not
      exist will result it one being automatically
      created for you using default values.


Version 1.38 - 15th June 2006
    + Fixed a major bug introduced in v1.37 where
      add_source() method appends new data sources
      instead of prepends. This would have swapped
      historical RRA data with different data source
      names if a new source was added during use
      of version 1.37.

    + Added examples/loadavg.pl

    + Modified examples/meminfo.pl to create
      swap-*.png graphs if /proc/meminfo is
      available.


Version 1.37 - 15th June 2006
    + Changed the add_source() method so that new
      data sources will be appended to the existing
      data sources, instead of prepended as was done
      before. This is useful if you are updating
      your RRD file directly with RRDs.pm and are
      assuming the order of the data source names
      in the RRD file.

    + Added ability to use the STACK draw type in
      the graph() method. See examples/vmstat.pl and
      examples/vmstat-cpu-daily.png an example of
      how to use it and what the results can look
      like.

    + Added a couple more tests to t/26add_source.t

    + $RRD::Simple::DEFAULT_DSTYPE and
      $RRD::Simple::DEBUG will now no longer be
      reset/overwritten when loading RRD::Simple,
      if the values were already defined. The
      existing documented logic will still work
      as expected, assuming you do not explicitly
      set the variable before loading RRD::Simple.
      This behaviour is intented to reduce confusion.

    + Added examples/processes.pl


Version 1.36 - 13th June 2006
    + Changed unit tests to skip tests if they find
      that RRDs is not actually installed. RRDs is
      clearly marked as a prerequisite for RRD::Simple
      to work. The module should not even build if
      RRDs is not installed. Submitting failed CPAN
      tester reports because you failed to install
      the prerequisite modules is stupid.

    + Added some brief instructions to INSTALL for
      installing RRDtool and RRDs.

    + Added a README in the examples directory to
      help briefly describe what each script does.

    + Changed the following three modules used in
      unit tests to be reccomended instead of required
      for building, since the unit tests will quite
      happily skip if they are not installed:
            'Test::Pod'           => 1.20,
            'Test::Pod::Coverage' => 1.06,
            'Test::Deep'          => 0.093,

    + Build.PL now makes an extra special point of
      warning about missing RRDs.pm, stating where a
      copy of RRDtool can be downloaded from, and
      that more details can be found in INSTALL.

    + Corrected a typo in examples/vmstat.pl in the
      command line for vmstat.


Version 1.35 - 10th June 2006
    + Added some more example images and scripts in
      the examples/ directory, and finished off
      examples/iostat.pl and examples/df.pl.

    + Added the "extended_legend" option to the graph()
      method, to include recent values to be printed
      next to the labels.

    + Changed the order of the default set of colours
      used to draw data sources in the graph() method,
      and altered the second and third shade cycles to
      make the colours slights more easily
      distingustable from one another.


Version 1.34 - 1st June 2006
    + Fixed a small gotcha whereby _ and - characters
      were not allowed in the "basename" paramater
      passed to the graph() method.

    + Fixed a typo in the code setting $VERSION.


Version 1.33 - 1st May 2006
    + Changed the default scheme from being 'year' to
      'mrtg' instead.

    + Added the "source_drawtypes" option to the graph
      method, so that AREA as well as LINE types can
      be plotted.

    + Renamed the t/*.t unit test files and did a little
      bit of refactoring of them. It's planned to
      improve upon them in the future.


Version 1.32 - 8th February 2006
    + No longer set alt-autoscale and alt-y-grid to
      on by default when creating graphs.

    + Changed the graph() method to default the end
      time for the graph to the last time the RRD
      was updated, instead of the current time.

    + Changed the default RRAs that are created in
      RRD files to be only AVERAGE and MAX. This is to
      reduce the file size and update times. To create
      RRD files with MIN and LAST CFs you can still use
      the "cf" parameter in the new() constructor method.

    + Changed the retention schemes to be more uniform
      and added an "mrtg" scheme that mimics the MRTG
      retention priod.

    + Updated unit tests to cope with code changes.


Version 1.31 - 19th January 2006
    + Fixed POD unit tests to run the right tests

    + Added more unit tests.

    + Added retention_period() to exports and documented
      in the POD

    + Bug fix whereby the add_source() wasn't finding
      the best heartbeat (it was returning a source
      name in some internal code instead of the correct
      integer value).

    + Added functionality for the graph() method to check
      what RRA CFs are available before blindly graphing
      the AVERAGE CF type. It will select best of the CFs
      available, in order of preference, AVERAGE, MAX,
      MIN, LAST.

    + Added (undocumented) "cf" parameter inside the
      new() constructor method to specify which CFs to use
      when creating RRAs in a new RRD file. This may be
      documented later if it's considered useful, and if
      the parameter name is correct (ie, shouldn't be
      named something else), or implemented in another way.

    + Fixed a bug which (until this release) would not
      and should not have been noticed since it only
      effected the passing of default values to the
      RRD::Simple $self object when used with indirect
      method calls requiring the new "cf" paramater.


Version 1.30 - 15th January 2006
    + Removed notice about add_source() not working with
      latest versions of RRD from the POD.

    + Added Test::Pod and Test::Pod::Coverage unit tests

    + The graph() method now allows arrays to be passed
      as key value options, thus allowing many --colour
      values to be set

    + Added the "source_colors" parameter to the graph()
      method to specify the plotted data source line colours

    + Added the "source_labels" parameter to the graph()
      method to specify data source labels in the legend/key

    + Changed the add_source() method to try and use
      the RRDs module for all the needed rrdtool
      functionality, instead of having to spawn an external
      copy of the rrdtool binary. A patch submitted to
      Tobi on 2006/01/08 which should be available in the
      1.2.13 release of rrdtool will allow RRDs::dump to
      dump to a filename instead of STDOUT, this removing
      the need for RRD::Simple to use the rrdtool binary
      at all.

    + Tweaked POD a little

    + Fixed some typos in the code where "3year" and "3years"
      were being mixed up. They have all been changed to be
      "3years" now, as per the POD.

    + Added the retention_period() method to return (in 
      seconds) how long the RRD will store data for.

    + The graph() method will now only generate graphs which
      the RRD file has enough data for. (ie, a 1 week long
      RRD file will not try and generate a 3 year graph etc)

    + Fixed a bug whereby the create() method and the graph()
      method were both getting the same values back from the
      _seconds_in() function, which should not be the case.
      This was resulting in blocky graphs because there was
      not enough margin between RRA boundies to ensure that
      each graph was getting the highest resolution data that
      you would expect. Also, _seconds_in() was returning
      slightly too high values, which indirectly caused the
      X asis labels to overlap eachother in some instances.


Version 1.29 - 6th January 2006
    + Improved makefile version extraction.

    + Changed license to Apache 2.0
      http://www.apache.org/licenses/LICENSE-2.0

    + Changed escaping on date in graph() to only happen
      with RRDs version 1.2 or greater (escaping should not
      be used with version 1.0)

    + Changed how the last values are pulled from the RRA
      in the last_values() method so it's more reliable
      now.

    + Fixed add_source() to work with rrdtool 1.2x and RRD
      version 0003 files.

    + Added /usr/local/rrdtool*/bin/ to the search path
      when looking for the rrdtool binary.

    + Tweaked Makefile.PL


Version 1.25 - 28th December 2005
    + Added Changes file.

    + Changed cluck warnings to only be output when perl
      warnings are enabled ($^W is set true).

    + t/04lazy_create_by_update.t
      t/07correct_spelling.t
      -- Disabled warnings being output for some unit tests
         so as not to alarm people. (The warnings are
         intentional when $^W is true, so it is deliberately
         set to false for those tests).

    + Modified Makefile.PL to send anonymous information to
      http://perlgirl.org.uk/lib/usage.cgi if the user
      agrees. This is so I can track which of my modules
      are most heavily used and on what platforms, so I can
      concentrate on maintaning the most popular ones in
      my limited spare time.


Version 1.24 - 26th December 2005
    + Added explicit specification of a data retention
      period (internally to RRD::Simple called a scheme).

    + Added checking of RRD file versions before
      attempting to add a new data source to an existing
      RRD file. add_source() can only be used on RRD
      version 001 files at the moment (rrdtool version
      1.0.x). Unit tests have been updated to take this
      in to account and skip if necessary.

    + Tidied and improved some of the error messages that
      are returned if the addition of a new data source
      to an existing RRD file fails.

    + Fixed escaping of the time date stamp that is added
      to the graphs so that it is compatible with rrdtool
      version 1.2.x.

    + Altered parsing of arguments to the graph() method
      so that _ characters are converted to - characters
      before passing to the RRDs module. This negated the
      need to quote a number or arguments that are passed
      in to the graph() method.

    + Added some more comments in the code.

    + Added some more POD.


Version 1.21 - 14th December 2005
    + Added examples/ApacheAccessLogActivity.pl
      -- Example script to import apache access log
         files in to a simple RRD file for graphing

    + Fixed a bug in the update() method to allow explicit
      specification of data insertion time. Previously if no
      RRD file was specified, the explicitly specified
      insertion time would have incorrectly been used as the
      RRD filename.

    + Added an experimental last_values() method to return
      the last values stored in the LAST CF RRA. This is not
      currently documented because it does not function as
      you would logically expect.

    + Added t/09last_value.t
      -- This test is essentially skipped because the output
         is not as you might expect. It will be enabled once
         the last_values() method is working better.

    + Added the 'basename' argument to the graph() method.

    + Added the 'sources' argument to the graph() method.

    + Fixed a few minor typos in warning messages.

    + Added more POD.

    + Improved unit tests.