Service_Weather for Developers Part 1

As promised in my last post, here is a basic run down on using Horde_Service_Weather in your own projects.

First, make sure you have the package installed. As of this writing, the latest available packaged release is 1.0.0RC2:

If you have not yet installed any Horde 4 packages, you will need to setup PEAR for Horde 4 (this is not meant to be a HOWTO on installing Horde. See the Horde install docs for more information).

// If you have not yet discovered Horde's PEAR channel:
pear channel-discover pear.horde.org

// Install the package:
pear install horde/Horde_Service_Weather

Next, we need to decide on the actual weather data provider. I recommend using Wunderground, as it is, by far, the most complete of the available choices. It requires registration for at least a free developer's account. Once you have your API key, you can create the weather object:

// Parameters for all driver types
// Note that below we use the global $injector to get the HttpClient and Cache instances.
// If not using the $injector, substitute your own instances in place of the $injector call.
$params = array(
    'http_client' => $injector->createInstance('Horde_Core_Factory_HttpClient')->create(),
    'cache' => $injector->getInstance('Horde_Cache'),
    'cache_lifetime' => 3600
);
$params['apikey'] = 'yourAPIKey';
$weather = new Horde_Service_Weather_WeatherUnderground($params);

Of course, if you choose to use, e.g., Google instead of Wunderground, just create the appropriate object:

// Google returns already localized strings,
// just pass it your language code.
$params['language'] = 'en';
$weather = new Horde_Service_Weather_Google($params);

Now we have our weather object, connected to the desired backend data provider. Let's fetch some weather information:

// Set the desired units
// Defaults to Horde_Service_Weather::UNITS_STANDARD
$weather->units = Horde_Service_Weather::UNITS_METRIC;

// Get current conditions.
// The location identifier can take a wide range of formats.
$conditions = $weather->getCurrentConditions('boston,ma');

// Unit labels
$units = $weather->getUnits();

// Basic condition description:
// e.g., "Sunny" or "Partly Cloudy" etc.
echo $conditions->condition;

// Current temp
echo $conditions->temp . $units['temp'];

Of course, lots of other properties are available. Check the documentation for details. Now, let's get a forecast:

// Get a 5 day forecast.
$forecast = $weather->getForecast('boston,ma', Horde_Service_Weather::FORECAST_5DAY);

// Each forecast result contains a collection of "Period" objects:
foreach ($forecast as $period) {
    echo 'Date: ' . (string)$period->date;  // Horde_Date object
    echo 'Hi: ' $period->high . $units['temp'];
    // Display other properties etc...
}

// If you want just a specific period:
$periodOne = $forecast->getForecastDay(0)
;
// Total snow accumulation for the day:
echo $periodOne->snow_total . $units['snow'];

Again, check the documentation for details on available properties.

In the next installment, we'll look at validating locations, searching locations and using a location autocompleter.

Have fun!