File Coverage

blib/lib/Geo/Coder/Google/V3.pm

Criterion	Covered	Total	%
statement	43	107	40.1
branch	5	40	12.5
condition	8	25	32.0
subroutine	9	15	60.0
pod	4	7	57.1
total	69	194	35.5

package Geo::Coder::Google::V3;

use strict;
use warnings;
our $VERSION = '0.19';

use Carp;
use JSON;
use HTTP::Request;
use LWP::UserAgent;
use URI;

my @ALLOWED_FILTERS = qw/route locality administrative_area postal_code country/;

sub new {
    my($class, %param) = @_;

    my $ua          = delete $param{ua}       || LWP::UserAgent->new(agent => __PACKAGE__ . "/$VERSION");
    my $host        = delete $param{host}     || 'maps.googleapis.com';
    my $language    = delete $param{language} || delete $param{hl};
    my $region      = delete $param{region}   || delete $param{gl};
    my $oe          = delete $param{oe}       || 'utf8';
    my $channel     = delete $param{channel}  || undef;
    my $client      = delete $param{client}   || '';
    my $key         = delete $param{key}      || '';
    my $components  = delete $param{components};

    bless {
        ua => $ua, host => $host, language => $language,
        region => $region, oe => $oe, channel => $channel,
        client => $client, key => $key, components => $components,
    }, $class;
}

sub ua {
    my $self = shift;
    if (@_) {
        $self->{ua} = shift;
    }
    $self->{ua};
}

sub reverse_geocode {
    my $self = shift;

    my %param;
    if (@_ % 2 == 0) {
        %param = @_;
    } else {
        $param{latlng} = shift;
    }

    my $latlng = $param{latlng}
        or Carp::croak("Usage: reverse_geocode(latlng => \$latlng)");

    return $self->geocode(location => $latlng, reverse => 1);
};

sub geocode {
    my $self = shift;

    my %param;
    if (@_ % 2 == 0) {
        %param = @_;
    } else {
        $param{location} = shift;
    }

    my $location = $param{location}
        or Carp::croak("Usage: geocode(location => \$location)");

    my $loc_param = $param{reverse} ? 'latlng' : 'address';

    my $uri = URI->new("https://$self->{host}/maps/api/geocode/json");
    my %query_parameters = ($loc_param => $location);
    $query_parameters{language} = $self->{language} if defined $self->{language};
    $query_parameters{region} = $self->{region} if defined $self->{region};
    $query_parameters{oe} = $self->{oe};
    $query_parameters{channel} = $self->{channel} if defined $self->{channel};
    my $components_params = $self->_get_components_query_params;
    $query_parameters{components} = $components_params if defined $components_params;
    $query_parameters{key} = $self->{key} if defined $self->{key};
    $uri->query_form(%query_parameters);
    my $url = $uri->as_string;

    # Process Maps Premier account info
    if ($self->{client} and $self->{key}) {
        delete $query_parameters{key};
        $query_parameters{client} = $self->{client};
        $uri->query_form(%query_parameters);

        my $signature = $self->make_signature($uri);
        # signature must be last parameter in query string or you get 403's
        $url = $uri->as_string;
        $url .= '&signature='.$signature if $signature;
    }

    my $res = $self->{ua}->get($url);

    if ($res->is_error) {
        Carp::croak("Google Maps API returned error: " . $res->status_line);
    }

    my $json = JSON->new->utf8;
    my $data = $json->decode($res->content);

    unless ($data->{status} eq 'OK' || $data->{status} eq 'ZERO_RESULTS') {
        Carp::croak(sprintf "Google Maps API returned status '%s'", $data->{status});
    }

    my @results = @{ $data->{results} || [] };
    wantarray ? @results : $results[0];
}

# methods below adapted from
# http://gmaps-samples.googlecode.com/svn/trunk/urlsigning/urlsigner.pl
sub decode_urlsafe_base64 {
  my ($self, $content) = @_;

  $content =~ tr/-/\+/;
  $content =~ tr/_/\//;

  return MIME::Base64::decode_base64($content);
}

sub encode_urlsafe{
  my ($self, $content) = @_;
  $content =~ tr/\+/\-/;
  $content =~ tr/\//\_/;

  return $content;
}

sub make_signature {
  my ($self, $uri) = @_;

  require Digest::HMAC_SHA1;
  require MIME::Base64;

  my $key = $self->decode_urlsafe_base64($self->{key});
  my $to_sign = $uri->path_query;

  my $digest = Digest::HMAC_SHA1->new($key);
  $digest->add($to_sign);
  my $signature = $digest->b64digest;

  return $self->encode_urlsafe($signature);
}

# Google API wants the components formatted in the following way:
# :|:|....|:
sub _get_components_query_params {
    my ($self, ) = @_;
    my $components = $self->{components};

    my @validated_components;
    foreach my $filter (sort keys %$components ) {
        next unless grep {$_ eq $filter} @ALLOWED_FILTERS;
        my $value = $components->{$filter};
        if (!defined $value) {
            Carp::croak("Value not specified for filter $filter");
        }
        # Google API expects the parameter to be passed as :
        push @validated_components, "$filter:$value";
    }
    return unless @validated_components;
    return join('|', @validated_components);
}

1;
__END__