Question

I have problems with this line,
OpenLayers.ProxyHost = “proxy.cgi?url=”;

What should do other than writing above line in open layer code set?

My information
I try to get feature information of WMS image using WMSGetFeatureInfo command.I am using openlayer 2.10 ,geoserver and apache-tomcat-6.0.35.I can run tomcat using localhost:8080 and geoserver using localhost:8080/geoserver.

I am new to open layer and i see Frequently Asked Questions about the OpenLayers project but still can’t figure out the answer.Yours any answers are very help full for me?

Thanks for your valuable time.

Answer 1

This link could be useful: Openlayers Proxy path usage

Some of the tasks that OpenLayers performs (including WFS requests) require the use of a proxy script because of restrictions in JavaScript on the use of XMLHTTPRequest making requests to remote servers.
Add that specific declaration before setting the map.

Start from here:
http://openlayers.org/dev/examples/2

Example of code:

    /*
     * Fix for OpenLayers using 900913 for web mercator and AGS using 102113 (it must run before map init)
    OpenLayers.Layer.WMS.prototype.getFullRequestString = function(newParams,altUrl) {
        try {
            var projectionCode=typeof this.options.projection == 'undefined' ? this.map.getProjection() : this.options.projection;
        } catch(err){
            var projectionCode=this.map.getProjection();
        }
        this.params.SRS = projectionCode=="none" ? null : projectionCode;
        return OpenLayers.Layer.Grid.prototype.getFullRequestString.apply(this,arguments);
    }

*/

    OpenLayers.ProxyHost = proxyPath;

    var options = {
        projection: mercator, //EPSG:3785/900913
        displayProjection: geographic, //EPSG:4326
        theme: null,
        maxExtent: new OpenLayers.Bounds(-20037508.34, -20037508.34, 20037508.34, 20037508.34),
        maxResolution: 156543.0339,
        units: 'm',
        controls: [],
        numZoomLevels: MAX_ZOOM_LEVEL,
        allOverlays: true
    };
    OpenLayers.Util.DEFAULT_PRECISION = 18;

    mp = new OpenLayers.Map('map', options);
    addMaps();
    addControls();
    mp.addLayers([googlePhysical, googleSatellite, googleStreets, googleHybrid]);
    //Enabling the preferred layers with a delay of 450 to be able to load the external backgrounds
    setTimeout(setInitialLayersDiv, 450);

    if (!mp.getCenter()) {
        if (document.getElementById('userMapExtent').value != '') {
            var sExtent = document.getElementById('userMapExtent').value.split(',');
            mp.zoomToExtent(new OpenLayers.Bounds(sExtent[0], sExtent[1], sExtent[2], sExtent[3]), true);
        } else {
            mp.zoomToExtent(europeGoogleExtent);
        }
    }
    J('#google_loading').hide('slow');