--- lib/Finance/Quote.pm 2009-10-05 13:39:57.000000000 -0400
+++ lib/Finance/Quote.pm 2010-09-02 01:03:48.000000000 -0400
@@ -41,9 +41,11 @@
use vars qw/@ISA @EXPORT @EXPORT_OK @EXPORT_TAGS
$VERSION $TIMEOUT %MODULES %METHODS $AUTOLOAD
- $YAHOO_CURRENCY_URL $USE_EXPERIMENTAL_UA/;
+ $YAHOO_CURRENCY_URL $YAHOO_CURRENCY_QUOTES_URL
+ $USE_EXPERIMENTAL_UA/;
$YAHOO_CURRENCY_URL = "
http://uk.finance.yahoo.com/q?s=";
+$YAHOO_CURRENCY_QUOTES_URL = "
http://uk.finance.yahoo.com/d/quotes.csv?e=.csv&f=l&s=";
@ISA = qw/Exporter/;
@EXPORT = ();
@@ -238,36 +240,88 @@
return $amount if ($from eq $to); # Trivial case.
- my $ua = $this->user_agent;
+ sub primary_url {
+ my ($this,$from,$to) = @_;
- my $data = $ua->request(GET "${YAHOO_CURRENCY_URL}$from$to%3DX")->content;
- # The web page returns utf8 content which gives a warning when parsing $data
- # in HTML::Parser
- my $tb = HTML::TreeBuilder->new_from_content(decode_utf8($data));
-
- # Find the <div> with the data
- my $div = $tb->look_down('id','yfi_quote_summary_data');
- # Make sure there's a <div> to parse.
- return undef unless $div;
-
- # The first <b> should contain the quote
- my $rate_element=$div->look_down('_tag','b');
- # Make sure there's a <b> to parse.
- return undef unless $rate_element;
-
- my $exchange_rate=$rate_element->as_text;
-
- $exchange_rate =~ s/,// ; # solve a bug when conversion rate
- # involves thousands. yahoo inserts
- # a comma when thousands occur
-
- {
- local $^W = 0; # Avoid undef warnings.
-
- # We force this to a number to avoid situations where
- # we may have extra cruft, or no amount.
- return undef unless ($exchange_rate+0);
+ my $ua = $this->user_agent;
+
+ my $data = $ua->request(GET "${YAHOO_CURRENCY_URL}$from$to%3DX")->content;
+ # The web page returns utf8 content which gives a warning when parsing $data
+ # in HTML::Parser
+ my $tb = HTML::TreeBuilder->new_from_content(decode_utf8($data));
+
+ # Find the <div> with the data
+ my $div = $tb->look_down('id','yfi_quote_summary_data');
+ # Make sure there's a <div> to parse.
+ return undef unless $div;
+
+ # The first <b> should contain the quote
+ my $rate_element=$div->look_down('_tag','b');
+ # Make sure there's a <b> to parse.
+ return undef unless $rate_element;
+
+ my $exchange_rate=$rate_element->as_text;
+
+ $exchange_rate =~ s/,// ; # solve a bug when conversion rate
+ # involves thousands. yahoo inserts
+ # a comma when thousands occur
+ {
+ local $^W = 0; # Avoid undef warnings.
+ return undef unless ($exchange_rate+0);
+ }
+ return $exchange_rate * 1.0;
}
+
+
+ sub secondary_url {
+ my ($this,$from,$to) = @_;
+ # Check against alternative URL as the original URL gives a rate
+ # multiplied by 100 for some currencies, for instance for NOKGBP=X
+ # (compare with GBPNOK=X)
+ #
+ # The alternative "CSV download" URL does not have this problem
+ # and don't require any screenscrapingm but the resolution is
+ # lower, typically just 2 digits, so we should only use it if we
+ # find a large difference from the original exchange rate.
+ #
+ # See
http://www.gummy-stuff.org/Yahoo-data.htm for details about the
+ # fields for the f= parameter.
+ my $ua = $this->user_agent;
+ my $quotes_rate = $ua->request(GET "${YAHOO_CURRENCY_QUOTES_URL}$from$to%3DX")->content;
+ {
+ # Avoid undef warnings.
+ local $^W = 0;
+ return undef unless ($quotes_rate+0);
+ }
+ return $quotes_rate * 1.0;
+ }
+
+ my $primary_rate = primary_url($this, $from, $to);
+ my $secondary_rate = secondary_url($this, $from, $to);
+ my $exchange_rate = $primary_rate;
+
+ if ( $primary_rate && $secondary_rate ) {
+ my $ratio = $primary_rate / $secondary_rate;
+ if ( $ratio < 0.5 || $ratio > 2 ) {
+ # Large difference, ignore $primary_rate
+ # (This seems to happen for NOK->GBP, DKK->USD)
+ if ( $ratio < 106 && $ratio > 94 ) {
+ # off by factor of 100, this is the typical error
+ $exchange_rate = $exchange_rate / 100;
+ }
+ else {
+ $exchange_rate = $secondary_rate;
+ }
+ # TODO: Work out the difference in scale (typically 100)
+ # and multiply the original $exchange_rate
+ }
+ } elsif ( !$primary_rate && $secondary_rate ) {
+ # $primary rate failed, fall back to secondary
+ $exchange_rate = $secondary_rate;
+ } elsif ( ! $exchange_rate ) {
+ return undef;
+ }
+
return ($exchange_rate * $amount);
}
