[RFC] Make Provider extends Geocoder

[MattKetmo]

One thing I'm not sure to understand is why there are both Geocoder and Provider interfaces.

Those 2 interfaces are almost identical (geocode() vs getGeocodedData() / reverse vs getReversedData()) and then bring no real value.

What I'm suggesting here is to make the Providers extending the Geocoders. Thus the ProviderBasedGeocoder just acts as an aggregator and each provider can be used individually as a valid Geocoder instance.

It facilitates the use of specific provider options and then it allows to bypass the level of abstraction I described at #322 (comment), which is for me the most blocking thing that prevent me from using this lib correctly.

In this PR I only fixed the GoogleMaps provider for the demo, and add a setRegion() method to it:

$adapter = new Ivory\HttpAdapter\CurlHttpAdapter();
$geocoder = new Geocoder\Provider\GoogleMaps($adapter);

$data = $geocoder->geocode('Toledo');
echo $data[0]->getCountry()->getCode(); // US

$geocoder->setRegion('ES');
$data = $geocoder->geocode('Toledo');
echo $data[0]->getCountry()->getCode(); // ES

Let me know what you think about it.

[willdurand]

Really interesting, thank you for this proposal, I like it!

[toin0u]

Very cool ! I like it as well 👍

[MattKetmo]

In fact I wonder if it's worthwhile to keep the Provider interface. We could drop the getName() method and specify it into the ProviderBasedGeocoder::registerProvider($name, Geocoder $geocoder) method (which could be renamed AggregateGeocoder::registerGeocoder($name, Geocoder $geocoder) ?).

[willdurand]

I was thinking about the AggregateGeocoder (or something like registry/aggregator/etc.)

[willdurand]

I don't like the registerProvider($name, $geocoder) signature, in fact, I'd like to avoid people to specify a "name"..

[willdurand]

Please, see #359