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NAME

Weather::Com - fetching weather information from weather.com

SYNOPSIS

  #!/usr/bin/perl -w
  use Weather::Com::Finder;

  # you have to fill in your ids from weather.com here
  my $PartnerId  = 'somepartnerid';
  my $LicenseKey = 'mylicense';

  my %weatherargs = (
        'partner_id' => $PartnerId,
        'license'    => $LicenseKey,
        'language'   => 'de',
  );

  my $weather_finder = Weather::Com::Finder->new(%weatherargs);
  
  my @locations = $weather_finder->find('Heidelberg');
  
  foreach my $location (@locations) {
    print "Found weather for city: ", $location->name(), "\n";
    print "Current Conditions are ", 
      $location->current_conditions()->description(), "\n";
  }

DESCRIPTION

Weather::Com provides three interfaces to access weather information from weather.com.

Except from the main high level interface, there is also a simple, very easy to use one called Weather::Com::Simple. And if you want, you can also use the low level interface that is the basis for the two high level interfaces, directly (Weather::Com::Cached or even Weather::Com::Base).

Please refer to the POD of these modules directly for detailed information.

The data provided by weather.com and made accessible by this OO interface can be used for free under special terms. Please have a look at the application programming guide of weather.com http://www.weather.com/services/xmloap.html

LOCALIZATION

Weather-Com uses Locale::Maketext for the l10n. Foreach language there has to be package Weather::Com::L10N::[langcode] (e.g. Weather::Com::L10N::de).

Localization is new with version 0.4 of Weather-Com. Therefore, there are not too many languages supported, yet. If one wants to create such a language definition package for a language that is not part of this module, please do the following:

  1. check my homepage to verify that the language package has not been created by someone else, yet (http://www.schnuecker.org/index.php?weather-com).

  2. contact me to verify if anybody else already is already translating into this language

  3. just do it and send me your new language package. It then will be first put onto my website for download and then it will be part of the next release.

Dynamic Language Support

With version 0.5 of Weather-Com I have introduced a new feature called dynamic language support.

The language for all textual attributes that usually are translated in your default language you chose while creating your Weather::Com::Finder instance can now dynamically be changed on a per-method-call basis.

Have a look at this example:

  #!/usr/bin/perl -w
  use Weather::Com::Finder;

  # you have to fill in your ids from weather.com here
  my $PartnerId  = 'somepartnerid';
  my $LicenseKey = 'mylicense';

  my %weatherargs = (
        'partner_id' => $PartnerId,
        'license'    => $LicenseKey,
        'language'   => 'en',
  );

  my $weather_finder = Weather::Com::Finder->new(%weatherargs);
  
  my @locations = $weather_finder->find('Heidelberg');
  
  foreach my $location (@locations) {
    print "Found weather for city: ", $location->name(), "\n";
    print "Current Conditions are ", 
      $location->current_conditions()->description(), "\n";
      
    # HERE WE USE DYNAMIC LANGUAGE SUPPORT
    print "That is in German: ",
      $location->current_conditions()->description('de'), "\n";
  }

As you can see in this example, you can provide a language tag to a method that returns textual information.

If you want to find out if the dynamic language support is already implemented for a specific attribute of one Weather-Com class, have a look at the corresponding packages POD.

TUTORIAL

The usual way to use the Weather::Com module would be to instantiate a Weather::Com::Finder that allows you to search for a location by a search string or postal code or whatever weather.com may understand.

The finder returns an arrayref or an array of locations (depending on how you call the find() method). Each location is an object of Weather::Com::Location.

The locations consist of location specific data, a Weather::Com::CurrentConditions object, a Weather::Com::Forecast object and a Weather::Com::Units object.

Configuration parameters

You will need a configuration hash to instantiate a Weather::Com::Finder object. Except of the partner_id and the license all parameters are optional and have sensible defaults.

  use Weather::Com::Finder;

  my %config = (
        partner_id => 'somepartnerid',  # mandatory
        license    => 'somelicensekey'  # mandatory
        language   => 'de',
        units      => 's',
        cache      => '/tmp/weather',
        timeout    => 300,
        debug      => 1,
        proxy      => 'http://some.proxy.de:8080',
        proxy_user => 'myaccount',
        proxy_pass => 'myproxy_pass'
  );

The valid parameters are:

partner_id => 'somepartnerid'

To be allowed to fetch weather information from weather.com you need to register (free of charge) to get a so called Partner Id and a License Key.

license => 'somelicensekey'

See partner_id.

language => 'somelanguagecode'

weather.com returns some textual data to describe the weather conditions, uv index, moon phase, wind direction, etc.

If one specifies a valid language as configuration parameter, this textual descriptions are translated into that language. If one specifies a language for that there's no translation, the objects will return the english texts.

cache => '/any/path'

Maybe you want to define a special path to put the cache files into. The cache directory defaults to ".".

units => s | m

This parameter defines whether to fetch information in metric (m) or US (s) format.

Defaults to 'm'.

timeout => some integer (in seconds)

The timeout for LWP::UserAgent to get an HTTP request done usually is set to 180s. If you need a longer timeout or for some reasons a shorter one you can set this here.

Defaults to 180 seconds.

debug => 0 | 1

Set debugging on/off.

Defaults to 0 (off).

proxy => 'none' | 'http://some.proxy.de:8080'

Usually no proxy is used by the LWP::UserAgent module used to communicate with weather.com. If you want to use an HTTP proxy you can specify one here.

proxy_user => undef | 'myuser'

If specified, this parameter is provided to the proxy for authentication purposes.

Defaults to undef.

proxy_pass => undef | 'mypassword'

If specified, this parameter is provided to the proxy for authentication purposes.

Defaults to undef.

Weather::Com::Finder

Usually one would start by searching for a location. This is done by instantiating a Weather::Com::Finder object providing all necessary information about the weather.com license, the proxy if one is needed, etc.

  my $finder = Weather::Com::Finder->new(%config);

Then you call the finders find() method to search for locations whose name or whose postal code matches against the searchstring. The finder then returns an array (or arrayref) of Weather::Com::Location objects.

  # if you want an array of locations:
  my @locations = $finder->find('Heidelberg');
  
  # or if you prefer an arrayref:
  my $locations = $finder->find('Heidelberg');

For further information please refer to Weather::Com::Finder.

Weather::Com::Location

The Weather::Com::Location object contains information about the location itself (longitude, latitude, current local time, etc.), a Weather::Com::Units object that contains all information about the units of messures currently used with this location, and a Weather::Com::CurrentConditions object containing the current weather conditions of the location.

  foreach my $location (@locations) {
        print "Found location with name: ", $location->name(), "\n";
        print "The longitude of this location is: ", $location->longitude(), "\n";
  }

All information in the Weather::Com::Location object is updated with each single call of one of its methods corresponding to the caching rules implemented in Weather::Com::Cached.

For detailed information about the Weather::Com::Location class please refer to Weather::Com::Location.

Weather::Com::Units

The units class provides all units of measure corresponding to the data of the location object. You'll get an instance of this class by calling the units() method of your location object.

For detailed information about the Weather::Com::Units class please refer to Weather::Com::Units.

Weather::Com::CurrentConditions

Each location has a Weather::Com::CurrentConditions object accessible via its current_conditions() method.

  my $conditions = $location->current_conditions();
  print "Current temperature is ", $conditions->temperature(), "°C\n";
  print "but it feels like ", $conditions->windchill(), "°C!\n";

Anytime you call a method of your Weather::Com::CurrentConditions object, its data is refreshed automatically if needed according to the caching rules.

For detailed information about this class please refer to Weather::Com::CurrentConditions.

Weather::Com::Forecast

Each location has a Weather::Com::Forecast object to access weather forecasts. weather.com provides up to 9 days of forecast - or 10 days if one wants to count day 0 which is today in most cases.

  my $forecast = $location->forecast();
  print "Max. temperature tomorrow will be ", $forecast->day(1)->high(), "°C\n";

Any time you call a method of your Weather::Com::Forecast object, forecast data is updated if necessary.

For detailed information about this class please refer to Weather::Com::Forecast.

Other classes

There are a some other classes that are used to represent groups of weather data like wind (speed, direction, etc.), UV index, air pressure, etc.

Objects of these classes belong to objects of class Weather::Com::CurrentConditions or Weather::Com::Forecast that will be introduced with the next release. These objects data will only refresh when you call the corresponding method of the parent object.

For detailed information about these classes please refer to their own POD.

Classes available with this version are:

Weather::Com::AirPressure

Provides access to the barometric pressure data.

For detailed information about this class please refer to Weather::Com::AirPressure.

Weather::Com::UVIndex

Provides access to the uv index of the parent object.

For detailed information about this class please refer to Weather::Com::UVIndex.

Weather::Com::Wind

Provides access to wind speed, maximum gust, direction in degrees, etc.

EXTENSIONS

If you plan to extend these module, e.g. with some other caching mechanisms, please contact me. Perhaps we can add your stuff to this module.

SEE ALSO

Detailed documentation of the main interface

Weather::Com::Finder, Weather::Com::Location, Weather::Com::Units, Weather::Com::CurrentConditions, Weather::Com::AirPressure, Weather::Com::UVIndex, Weather::Com::Wind

Detailed documentation of the Simple API

Weather::Com::Simple

Detailed documentation of the low level interface

Weather::Com::Cached and Weather::Com::Base

BUGS/SUPPORT/PRE-RELEASES

If you want to report a bug, please use the CPAN bug reporting tool.

If you have any question, suggestion, feature request, etc. please use the CPAN forum.

If you are looking for fixes, pre-releases, etc. have a look at my website http://www.schnuecker.org/index.php?weather-com.

AUTHOR

Thomas Schnuecker, <thomas@schnuecker.de>

COPYRIGHT AND LICENSE

Copyright (C) 2004-2007 by Thomas Schnuecker

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

The data provided by weather.com and made accessible by this OO interface can be used for free under special terms. Please have a look at the application programming guide of weather.com (http://www.weather.com/services/xmloap.html)

1 POD Error

The following errors were encountered while parsing the POD:

Around line 311:

Non-ASCII character seen before =encoding in '"°C\n";'. Assuming CP1252