Question

I decided to pull information from Google’s Weather API – The code I’m using below works fine.

            XmlDocument widge = new XmlDocument();
            widge.Load("https://www.google.com/ig/api?weather=Brisbane/dET7zIp38kGFSFJeOpWUZS3-");
            var weathlist = widge.GetElementsByTagName("current_conditions");
            foreach (XmlNode node in weathlist)
            {

                City.Text = ("Brisbane");
                CurCond.Text = (node.SelectSingleNode("condition").Attributes["data"].Value);
                Wimage.ImageUrl = ("http://www.google.com/" + node.SelectSingleNode("icon").Attributes["data"].Value);
                Temp.Text = (node.SelectSingleNode("temp_c").Attributes["data"].Value + "°C");
        }
     }

As I said, I am able to pull the required data from the XML file and display it, however if the page is refreshed or a current session is still active, I receive the following error:

WebException was unhandled by user code – The remote server returned
an error: 403 Forbidden Exception.

I’m wondering whether this could be to do with some kind of access limitation put on access to that particular XML file?

Further research and adaptation of suggestions

As stated below, this is by no means best practice, but I’ve included the catch I now use for the exception. I run this code on Page_Load so I just do a post-back to the page. I haven’t noticed any problems since. Performance wise I’m not overly concerned – I haven’t noticed any increase in load time and this solution is temporary due to the fact this is all for testing purposes. I’m still in the process of using Yahoo’s Weather API.

        try
        {
            XmlDocument widge = new XmlDocument();
            widge.Load("https://www.google.com/ig/api?weather=Brisbane/dET7zIp38kGFSFJeOpWUZS3-");
            var list2 = widge.GetElementsByTagName("current_conditions");
            foreach (XmlNode node in list2)
            {

                City.Text = ("Brisbane");
                CurCond.Text = (node.SelectSingleNode("condition").Attributes["data"].Value);
                Wimage.ImageUrl = ("http://www.google.com/" + node.SelectSingleNode("icon").Attributes["data"].Value);
                Temp.Text = (node.SelectSingleNode("temp_c").Attributes["data"].Value + "°C");

            }
        }
        catch (WebException exp)
        {
            if (exp.Status == WebExceptionStatus.ProtocolError &&
                exp.Response != null)
            {
                var webres = (HttpWebResponse)exp.Response;
                if (webres.StatusCode == HttpStatusCode.Forbidden)
                {
                    Response.Redirect(ithwidgedev.aspx);
                }

            }
        }

Google article illustrating API error handling

Google API Handle Errors

Thanks to:

https://stackoverflow.com/a/12011819/1302173 (Catch 403 and recall)

https://stackoverflow.com/a/11883388/1302173 (Error Handling and General Google API info)

https://stackoverflow.com/a/12000806/1302173 (Response Handling/json caching – Future plans)

Alternative

I found this great open source alternative recently

OpenWeatherMap – Free weather data and forecast API

Answer 1

This is related to a change / outage of the service. See: http://status-dashboard.com/32226/47728

I have been using Google’s Weather API for over a year to feed a phone server so that the PolyCom phones receive a weather page. It has run error free for over a year. As of August 7th 2012 there have been frequent intermittent 403 errors.

I make a hit of the service once per hour (As has always been the case) so I don’t think frequency of request is the issue. More likely the intermittent nature of the 403 is related to the partial roll-out of a configuration change or a CDN change at Google.

The Google Weather API isn’t really a published API. It was an internal service apparently designed for use on iGoogle so the level of support is uncertain. I tweeted googleapis yesterday and received no response.

It may be better to switch to a promoted weather API such as:
WUnderground Weather or
Yahoo Weather.

I have added the following ‘unless defined’ error handling perl code myself yesterday to cope with this but if the problem persists I will switch to a more fully supported service:

my $url = "http://www.google.com/ig/api?weather=" . $ZipCode ;

my $tpp = XML::TreePP->new();
my $tree = $tpp->parsehttp( GET => $url );

my $city = $tree->{xml_api_reply}->{weather}->{forecast_information}->{city}->{"-data"};

unless (defined($city)) {
    print "The weather service is currently unavailable. \n";
    open (MYFILE, '>/home/swarmp/public_html/status/polyweather.xhtml');
    print MYFILE qq(<?xml version="1.0" encoding="utf-8"?>\n);
    print MYFILE qq(<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "xhtml11.dtd">\n);
    print MYFILE qq(<html xmlns="http://www.w3.org/1999/xhtml">\n);
    print MYFILE qq(<head><title>Weather is Unavailable!</title></head>\n);
    print MYFILE qq(<body>\n);
    print MYFILE qq(<p>\n);
    print MYFILE qq(The weather service is currently unavailable from the data vendor.\n);
    print MYFILE qq(</p>\n);
    print MYFILE qq(</body>\n);
    print MYFILE qq(</html>\n);
    close MYFILE;
    exit(0);
}...