/* Copyright (c) 2006-2010 by OpenLayers Contributors (see authors.txt for
* full list of contributors). Published under the Clear BSD license.
* See http://svn.openlayers.org/trunk/openlayers/license.txt for the
* full text of the license. */
/**
* @requires OpenLayers/Control.js
* @requires OpenLayers/Handler/Click.js
* @requires OpenLayers/Handler/Hover.js
* @requires OpenLayers/Request.js
*/
/**
* Class: OpenLayers.Control.WMSGetFeatureInfo
* The WMSGetFeatureInfo control uses a WMS query to get information about a point on the map. The
* information may be in a display-friendly format such as HTML, or a machine-friendly format such
* as GML, depending on the server's capabilities and the client's configuration. This control
* handles click or hover events, attempts to parse the results using an OpenLayers.Format, and
* fires a 'getfeatureinfo' event with the click position, the raw body of the response, and an
* array of features if it successfully read the response.
*
* Inherits from:
* - <OpenLayers.Control>
*/
OpenLayers.Control.WMSGetFeatureInfo = OpenLayers.Class(OpenLayers.Control, {
/**
* APIProperty: hover
* {Boolean} Send GetFeatureInfo requests when mouse stops moving.
* Default is false.
*/
hover: false,
/**
* APIProperty: drillDown
* {Boolean} Drill down over all WMS layers in the map. When
* using drillDown mode, hover is not possible, and an infoFormat that
* returns parseable features is required. Default is false.
*/
drillDown: false,
/**
* APIProperty: maxFeatures
* {Integer} Maximum number of features to return from a WMS query. This
* sets the feature_count parameter on WMS GetFeatureInfo
* requests.
*/
maxFeatures: 10,
/** APIProperty: clickCallback
* {String} The click callback to register in the
* {<OpenLayers.Handler.Click>} object created when the hover
* option is set to false. Default is "click".
*/
clickCallback: "click",
/**
* Property: layers
* {Array(<OpenLayers.Layer.WMS>)} The layers to query for feature info.
* If omitted, all map WMS layers with a url that matches this <url> or
* <layerUrls> will be considered.
*/
layers: null,
/**
* Property: queryVisible
* {Boolean} If true, filter out hidden layers when searching the map for
* layers to query. Default is false.
*/
queryVisible: false,
/**
* Property: url
* {String} The URL of the WMS service to use. If not provided, the url
* of the first eligible layer will be used.
*/
url: null,
/**
* Property: layerUrls
* {Array(String)} Optional list of urls for layers that should be queried.
* This can be used when the layer url differs from the url used for
* making GetFeatureInfo requests (in the case of a layer using cached
* tiles).
*/
layerUrls: null,
/**
* Property: infoFormat
* {String} The mimetype to request from the server
*/
infoFormat: 'text/html',
/**
* Property: vendorParams
* {Object} Additional parameters that will be added to the request, for
* WMS implementations that support them. This could e.g. look like
* (start code)
* {
* radius: 5
* }
* (end)
*/
vendorParams: {},
/**
* Property: format
* {<OpenLayers.Format>} A format for parsing GetFeatureInfo responses.
* Default is <OpenLayers.Format.WMSGetFeatureInfo>.
*/
format: null,
/**
* Property: formatOptions
* {Object} Optional properties to set on the format (if one is not provided
* in the <format> property.
*/
formatOptions: null,
/**
* APIProperty: handlerOptions
* {Object} Additional options for the handlers used by this control, e.g.
* (start code)
* {
* "click": {delay: 100},
* "hover": {delay: 300}
* }
* (end)
*/
handlerOptions: null,
/**
* Property: handler
* {Object} Reference to the <OpenLayers.Handler> for this control
*/
handler: null,
/**
* Property: hoverRequest
* {<OpenLayers.Request>} contains the currently running hover request
* (if any).
*/
hoverRequest: null,
/**
* Constant: EVENT_TYPES
*
* Supported event types (in addition to those from <OpenLayers.Control>):
* beforegetfeatureinfo - Triggered before the request is sent.
* The event object has an *xy* property with the position of the
* mouse click or hover event that triggers the request.
* nogetfeatureinfo - no queryable layers were found.
* getfeatureinfo - Triggered when a GetFeatureInfo response is received.
* The event object has a *text* property with the body of the
* response (String), a *features* property with an array of the
* parsed features, an *xy* property with the position of the mouse
* click or hover event that triggered the request, and a *request*
* property with the request itself. If drillDown is set to true and
* multiple requests were issued to collect feature info from all
* layers, *text* and *request* will only contain the response body
* and request object of the last request.
*/
EVENT_TYPES: ["beforegetfeatureinfo", "nogetfeatureinfo", "getfeatureinfo"],
/**
* Constructor: <OpenLayers.Control.WMSGetFeatureInfo>
*
* Parameters:
* options - {Object}
*/
initialize: function(options) {
// concatenate events specific to vector with those from the base
this.EVENT_TYPES =
OpenLayers.Control.WMSGetFeatureInfo.prototype.EVENT_TYPES.concat(
OpenLayers.Control.prototype.EVENT_TYPES
);
options = options || {};
options.handlerOptions = options.handlerOptions || {};
OpenLayers.Control.prototype.initialize.apply(this, [options]);
if(!this.format) {
this.format = new OpenLayers.Format.WMSGetFeatureInfo(
options.formatOptions
);
}
if(this.drillDown === true) {
this.hover = false;
}
if(this.hover) {
this.handler = new OpenLayers.Handler.Hover(
this, {
'move': this.cancelHover,
'pause': this.getInfoForHover
},
OpenLayers.Util.extend(this.handlerOptions.hover || {}, {
'delay': 250
}));
} else {
var callbacks = {};
callbacks[this.clickCallback] = this.getInfoForClick;
this.handler = new OpenLayers.Handler.Click(
this, callbacks, this.handlerOptions.click || {});
}
},
/**
* Method: activate
* Activates the control.
*
* Returns:
* {Boolean} The control was effectively activated.
*/
activate: function () {
if (!this.active) {
this.handler.activate();
}
return OpenLayers.Control.prototype.activate.apply(
this, arguments
);
},
/**
* Method: deactivate
* Deactivates the control.
*
* Returns:
* {Boolean} The control was effectively deactivated.
*/
deactivate: function () {
return OpenLayers.Control.prototype.deactivate.apply(
this, arguments
);
},
/**
* Method: getInfoForClick
* Called on click
*
* Parameters:
* evt - {<OpenLayers.Event>}
*/
getInfoForClick: function(evt) {
this.events.triggerEvent("beforegetfeatureinfo", {xy: evt.xy});
// Set the cursor to "wait" to tell the user we're working on their
// click.
OpenLayers.Element.addClass(this.map.viewPortDiv, "olCursorWait");
this.request(evt.xy, {});
},
/**
* Method: getInfoForHover
* Pause callback for the hover handler
*
* Parameters:
* evt - {Object}
*/
getInfoForHover: function(evt) {
this.events.triggerEvent("beforegetfeatureinfo", {xy: evt.xy});
this.request(evt.xy, {hover: true});
},
/**
* Method: cancelHover
* Cancel callback for the hover handler
*/
cancelHover: function() {
if (this.hoverRequest) {
this.hoverRequest.abort();
this.hoverRequest = null;
}
},
/**
* Method: findLayers
* Internal method to get the layers, independent of whether we are
* inspecting the map or using a client-provided array
*/
findLayers: function() {
var candidates = this.layers || this.map.layers;
var layers = [];
var layer, url;
for(var i=0, len=candidates.length; i<len; ++i) {
layer = candidates[i];
if(layer instanceof OpenLayers.Layer.WMS &&
(!this.queryVisible || layer.getVisibility())) {
url = layer.url instanceof Array ? layer.url[0] : layer.url;
// if the control was not configured with a url, set it
// to the first layer url
if(this.drillDown === false && !this.url) {
this.url = url;
}
if(this.drillDown === true || this.urlMatches(url)) {
layers.push(layer);
}
}
}
return layers;
},
/**
* Method: urlMatches
* Test to see if the provided url matches either the control <url> or one
* of the <layerUrls>.
*
* Parameters:
* url - {String} The url to test.
*
* Returns:
* {Boolean} The provided url matches the control <url> or one of the
* <layerUrls>.
*/
urlMatches: function(url) {
var matches = OpenLayers.Util.isEquivalentUrl(this.url, url);
if(!matches && this.layerUrls) {
for(var i=0, len=this.layerUrls.length; i<len; ++i) {
if(OpenLayers.Util.isEquivalentUrl(this.layerUrls[i], url)) {
matches = true;
break;
}
}
}
return matches;
},
/**
* Method: buildWMSOptions
* Build an object with the relevant WMS options for the GetFeatureInfo request
*
* Parameters:
* url - {String} The url to be used for sending the request
* layers - {Array(<OpenLayers.Layer.WMS)} An array of layers
* clickPosition - {<OpenLayers.Pixel>} The position on the map where the mouse
* event occurred.
* format - {String} The format from the corresponding GetMap request
*/
buildWMSOptions: function(url, layers, clickPosition, format) {
var layerNames = [], styleNames = [];
for (var i = 0, len = layers.length; i < len; i++) {
layerNames = layerNames.concat(layers[i].params.LAYERS);
styleNames = styleNames.concat(this.getStyleNames(layers[i]));
}
var params = OpenLayers.Util.extend({
service: "WMS",
version: layers[0].params.VERSION,
request: "GetFeatureInfo",
layers: layerNames,
query_layers: layerNames,
styles: styleNames,
bbox: this.map.getExtent().toBBOX(null,
layers[0].reverseAxisOrder()),
feature_count: this.maxFeatures,
height: this.map.getSize().h,
width: this.map.getSize().w,
format: format,
info_format: this.infoFormat
}, (parseFloat(layers[0].params.VERSION) >= 1.3) ?
{
crs: this.map.getProjection(),
i: clickPosition.x,
j: clickPosition.y
} :
{
srs: this.map.getProjection(),
x: clickPosition.x,
y: clickPosition.y
}
);
OpenLayers.Util.applyDefaults(params, this.vendorParams);
return {
url: url,
params: OpenLayers.Util.upperCaseObject(params),
callback: function(request) {
this.handleResponse(clickPosition, request);
},
scope: this
};
},
/**
* Method: getStyleNames
* Gets the STYLES parameter for the layer. Make sure the STYLES parameter
* matches the LAYERS parameter
*
* Parameters:
* layer - {<OpenLayers.Layer.WMS>}
*
* Returns:
* {Array(String)} The STYLES parameter
*/
getStyleNames: function(layer) {
// in the event of a WMS layer bundling multiple layers but not
// specifying styles,we need the same number of commas to specify
// the default style for each of the layers. We can't just leave it
// blank as we may be including other layers that do specify styles.
var styleNames;
if (layer.params.STYLES) {
styleNames = layer.params.STYLES;
} else {
if (layer.params.LAYERS instanceof Array) {
styleNames = new Array(layer.params.LAYERS.length);
} else { // Assume it's a String
styleNames = layer.params.LAYERS.replace(/[^,]/g, "");
}
}
return styleNames;
},
/**
* Method: request
* Sends a GetFeatureInfo request to the WMS
*
* Parameters:
* clickPosition - {<OpenLayers.Pixel>} The position on the map where the
* mouse event occurred.
* options - {Object} additional options for this method.
*
* Valid options:
* - *hover* {Boolean} true if we do the request for the hover handler
*/
request: function(clickPosition, options) {
var layers = this.findLayers();
if(layers.length == 0) {
this.events.triggerEvent("nogetfeatureinfo");
// Reset the cursor.
OpenLayers.Element.removeClass(this.map.viewPortDiv, "olCursorWait");
return;
}
options = options || {};
if(this.drillDown === false) {
var wmsOptions = this.buildWMSOptions(this.url, layers,
clickPosition, layers[0].params.FORMAT);
var request = OpenLayers.Request.GET(wmsOptions);
if (options.hover === true) {
this.hoverRequest = request;
}
} else {
this._requestCount = 0;
this._numRequests = 0;
this.features = [];
// group according to service url to combine requests
var services = {}, url;
for(var i=0, len=layers.length; i<len; i++) {
var layer = layers[i];
var service, found = false;
url = layer.url instanceof Array ? layer.url[0] : layer.url;
if(url in services) {
services[url].push(layer);
} else {
this._numRequests++;
services[url] = [layer];
}
}
var layers;
for (var url in services) {
layers = services[url];
var wmsOptions = this.buildWMSOptions(url, layers,
clickPosition, layers[0].params.FORMAT);
OpenLayers.Request.GET(wmsOptions);
}
}
},
/**
* Method: triggerGetFeatureInfo
* Trigger the getfeatureinfo event when all is done
*
* Parameters:
* request - {XMLHttpRequest} The request object
* xy - {<OpenLayers.Pixel>} The position on the map where the
* mouse event occurred.
* features - {Array(<OpenLayers.Feature.Vector>)}
*/
triggerGetFeatureInfo: function(request, xy, features) {
this.events.triggerEvent("getfeatureinfo", {
text: request.responseText,
features: features,
request: request,
xy: xy
});
// Reset the cursor.
OpenLayers.Element.removeClass(this.map.viewPortDiv, "olCursorWait");
},
/**
* Method: handleResponse
* Handler for the GetFeatureInfo response.
*
* Parameters:
* xy - {<OpenLayers.Pixel>} The position on the map where the
* mouse event occurred.
* request - {XMLHttpRequest} The request object.
*/
handleResponse: function(xy, request) {
var doc = request.responseXML;
if(!doc || !doc.documentElement) {
doc = request.responseText;
}
var features = this.format.read(doc);
if (this.drillDown === false) {
this.triggerGetFeatureInfo(request, xy, features);
} else {
this._requestCount++;
this._features = (this._features || []).concat(features);
if (this._requestCount === this._numRequests) {
this.triggerGetFeatureInfo(request, xy, this._features.concat());
delete this._features;
delete this._requestCount;
delete this._numRequests;
}
}
},
CLASS_NAME: "OpenLayers.Control.WMSGetFeatureInfo"
});