--- a/labs/openlayers/lib/OpenLayers/Layer/MapServer.js +++ b/labs/openlayers/lib/OpenLayers/Layer/MapServer.js @@ -1,1 +1,200 @@ - +/* 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/Layer/Grid.js + */ + +/** + * Class: OpenLayers.Layer.MapServer + * Instances of OpenLayers.Layer.MapServer are used to display + * data from a MapServer CGI instance. + * + * Inherits from: + * - <OpenLayers.Layer.Grid> + */ +OpenLayers.Layer.MapServer = OpenLayers.Class(OpenLayers.Layer.Grid, { + + /** + * Constant: DEFAULT_PARAMS + * {Object} Hashtable of default parameter key/value pairs + */ + DEFAULT_PARAMS: { + mode: "map", + map_imagetype: "png" + }, + + /** + * Constructor: OpenLayers.Layer.MapServer + * Create a new MapServer layer object + * + * Parameters: + * name - {String} A name for the layer + * url - {String} Base url for the MapServer CGI + * (e.g. http://www2.dmsolutions.ca/cgi-bin/mapserv) + * params - {Object} An object with key/value pairs representing the + * GetMap query string parameters and parameter values. + * options - {Ojbect} Hashtable of extra options to tag onto the layer + */ + initialize: function(name, url, params, options) { + var newArguments = []; + newArguments.push(name, url, params, options); + OpenLayers.Layer.Grid.prototype.initialize.apply(this, newArguments); + + this.params = OpenLayers.Util.applyDefaults( + this.params, this.DEFAULT_PARAMS + ); + + // unless explicitly set in options, if the layer is transparent, + // it will be an overlay + if (options == null || options.isBaseLayer == null) { + this.isBaseLayer = ((this.params.transparent != "true") && + (this.params.transparent != true)); + } + }, + + /** + * Method: clone + * Create a clone of this layer + * + * Returns: + * {<OpenLayers.Layer.MapServer>} An exact clone of this layer + */ + clone: function (obj) { + if (obj == null) { + obj = new OpenLayers.Layer.MapServer(this.name, + this.url, + this.params, + this.getOptions()); + } + //get all additions from superclasses + obj = OpenLayers.Layer.Grid.prototype.clone.apply(this, [obj]); + + // copy/set any non-init, non-simple values here + + return obj; + }, + + /** + * Method: addTile + * Creates a tile, initializes it, and adds it to the layer div. + * + * Parameters: + * bounds - {<OpenLayers.Bounds>} + * position - {<OpenLayers.Pixel>} + * + * Returns: + * {<OpenLayers.Tile.Image>} The added OpenLayers.Tile.Image + */ + addTile:function(bounds,position) { + return new OpenLayers.Tile.Image(this, position, bounds, + null, this.tileSize); + }, + + /** + * Method: getURL + * Return a query string for this layer + * + * Parameters: + * bounds - {<OpenLayers.Bounds>} A bounds representing the bbox + * for the request + * + * Returns: + * {String} A string with the layer's url and parameters and also + * the passed-in bounds and appropriate tile size specified + * as parameters. + */ + getURL: function (bounds) { + bounds = this.adjustBounds(bounds); + // Make a list, so that getFullRequestString uses literal "," + var extent = [bounds.left, bounds. bottom, bounds.right, bounds.top]; + + var imageSize = this.getImageSize(); + + // make lists, so that literal ','s are used + var url = this.getFullRequestString( + {mapext: extent, + imgext: extent, + map_size: [imageSize.w, imageSize.h], + imgx: imageSize.w / 2, + imgy: imageSize.h / 2, + imgxy: [imageSize.w, imageSize.h] + }); + + return url; + }, + + /** + * Method: getFullRequestString + * combine the layer's url with its params and these newParams. + * + * Parameter: + * newParams - {Object} New parameters that should be added to the + * request string. + * altUrl - {String} (optional) Replace the URL in the full request + * string with the provided URL. + * + * Returns: + * {String} A string with the layer's url and parameters embedded in it. + */ + getFullRequestString:function(newParams, altUrl) { + // use layer's url unless altUrl passed in + var url = (altUrl == null) ? this.url : altUrl; + + // create a new params hashtable with all the layer params and the + // new params together. then convert to string + var allParams = OpenLayers.Util.extend({}, this.params); + allParams = OpenLayers.Util.extend(allParams, newParams); + var paramsString = OpenLayers.Util.getParameterString(allParams); + + // if url is not a string, it should be an array of strings, + // in which case we will deterministically select one of them in + // order to evenly distribute requests to different urls. + if (url instanceof Array) { + url = this.selectUrl(paramsString, url); + } + + // ignore parameters that are already in the url search string + var urlParams = OpenLayers.Util.upperCaseObject( + OpenLayers.Util.getParameters(url)); + for(var key in allParams) { + if(key.toUpperCase() in urlParams) { + delete allParams[key]; + } + } + paramsString = OpenLayers.Util.getParameterString(allParams); + + // requestString always starts with url + var requestString = url; + + // MapServer needs '+' seperating things like bounds/height/width. + // Since typically this is URL encoded, we use a slight hack: we + // depend on the list-like functionality of getParameterString to + // leave ',' only in the case of list items (since otherwise it is + // encoded) then do a regular expression replace on the , characters + // to '+' + // + paramsString = paramsString.replace(/,/g, "+"); + + if (paramsString != "") { + var lastServerChar = url.charAt(url.length - 1); + if ((lastServerChar == "&") || (lastServerChar == "?")) { + requestString += paramsString; + } else { + if (url.indexOf('?') == -1) { + //serverPath has no ? -- add one + requestString += '?' + paramsString; + } else { + //serverPath contains ?, so must already have paramsString at the end + requestString += '&' + paramsString; + } + } + } + return requestString; + }, + + CLASS_NAME: "OpenLayers.Layer.MapServer" +}); +