{ Hi! I'm Mike }
I'm a core developer with The Horde Project and a founding parter of Horde LLC - the company behind the world's most flexible groupware platform. This is my personal blog full of random thoughts about development and life in general.
December 23, 2011

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!

December 22, 2011

Service_Weather

With the recent discontinuation of The Weather Channel's public API access, Horde was left without a data feed for weather information other than the aviation style METAR/TAF reports. Weather information has historically been used  in two places in Horde; The WeatherDotCom portal block, and in the Timeobjects module, where we export the weather information to other applications - like Kronolith, Horde's calendaring application.

After an audit of available (and free) weather services, I settled on the following three services as suitable as alternatives to TWC's dead data feed.

Weather Underground: Of the three providers we decided to support, this one provides the most detailed data. You must sign up for an account for your Horde install. There is a free "developer" account option, though it does have relatively low usage limits which may be a problem if you have a large user base. We of course cache every request to help with getting the most out of those limits. They also offer very reasonable paid options as well.

World Weather Online: Another free service that provides a fair amount of data, though it's not as detailed as Weather Underground. Free account required, with higher limits than Weather Underground.

Google: Google does not provide an official weather API, but they do have an API interface that is used internally for Google's weather portal block. The data provided is not very detailed, but if you are looking for a provider that does not require any registration, this might be a solution for you.  No registration, no known limits, though this is unofficial, so keep that in mind.

It's worth noting that the biggest thing missing, even from Weather Underground's feed is the day/night forecast style. They provide an hourly forecast, but no simple day/night forecast. The non-hourly forecast data is provided as a single set of conditions for the entire day. Another fairly well known provider AccuWeather, appears to provide this (and fairly detailed data as well), but sadly, they have informed me that they no longer provide free data feeds - even for FOSS projects. Also, before anyone asks, yes I did look at Yahoo's weather feed. This is an RSS feed, which in and of itself is not a problem, but they only provided very basic data, for only a day or two in the future...not enough for our needs.

The end result of all this is the new Horde_Service_Weather library, a new Weather block, and support for the new weather drivers in the Timeobjects application for exporting the weather to applications like Kronolith.  As a side effect of all this, the weather support in Horde has, IMO, been greatly improved. The weather portal block code received a much needed overhaul including the ability to dynamically change the location being displayed directly from the portal screen, along with autocompletion of the locations.

At the time of this writing, Service_Weather is in Beta, and available via Horde's PEAR server. The new weather block is included in the most recent Horde release, and the latest Timeobjects release contains support for the new code as well.

For developers interested in learning how to use Service_Weather in their own applications - look forward to a blog entry in the near future detailing the usage.