Subversion Repositories Applications.papyrus

if(!dojo._hasResource["dojox.data.QueryReadStore"]){ //_hasResource checks added by build. Do not use _hasResource directly in your code.
dojo._hasResource["dojox.data.QueryReadStore"] = true;
dojo.provide("dojox.data.QueryReadStore");
dojo.provide("dojox.data.QueryReadStore.InvalidItemError");
dojo.provide("dojox.data.QueryReadStore.InvalidAttributeError");

dojo.require("dojo.string");
dojo.require("dojo.data.util.simpleFetch");

dojo.declare("dojox.data.QueryReadStore", null, {
        /*
        //      summary:
        //              This class provides a store that is mainly intended to be used
        //              for loading data dynamically from the server, used i.e. for
        //              retreiving chunks of data from huge data stores on the server (by server-side filtering!).
        //              Upon calling the fetch() method of this store the data are requested from
        //              the server if they are not yet loaded for paging (or cached).
        //
        //              For example used for a combobox which works on lots of data. It
        //              can be used to retreive the data partially upon entering the
        //              letters "ac" it returns only items like "action", "acting", etc.
        //
        //  note:
        //      The field name "id" in a query is reserved for looking up data
        //      by id. This is necessary as before the first fetch, the store
        //      has no way of knowing which field the server will declare as
        //      identifier.
        //
        //      examples:
        //              // The parameter "query" contains the data that are sent to the server.
        //              var store = new dojox.data.QueryReadStore({url:'/search.php'});
        //              store.fetch({query:{name:'a'}, queryOptions:{ignoreCase:false}});
        //
        //              // Since "serverQuery" is given, it overrules and those data are
        //              // sent to the server.
        //              var store = new dojox.data.QueryReadStore({url:'/search.php'});
        //              store.fetch({serverQuery:{name:'a'}, queryOptions:{ignoreCase:false}});
        //
        //      todo:
        //              - there is a bug in the paging, when i set start:2, count:5 after an initial fetch() and doClientPaging:true
        //                it returns 6 elemetns, though count=5, try it in QueryReadStore.html
        //              - allow configuring if the paging shall takes place on the client or the server
        //              - add optional caching
        //              - when the first query searched for "a" and the next for a subset of
        //                the first, i.e. "ab" then we actually dont need a server request, if
        //                we have client paging, we just need to filter the items we already have
        //                that might also be tooo much logic
        */
        
        url:"",
        requestMethod:"get",
        //useCache:false,
        
        // We use the name in the errors, once the name is fixed hardcode it, may be.
        _className:"dojox.data.QueryReadStore",
        
        // This will contain the items we have loaded from the server.
        // The contents of this array is optimized to satisfy all read-api requirements
        // and for using lesser storage, so the keys and their content need some explaination:
        //              this._items[0].i - the item itself 
        //              this._items[0].r - a reference to the store, so we can identify the item
        //                      securly. We set this reference right after receiving the item from the
        //                      server.
        _items:[],
        
        // Store the last query that triggered xhr request to the server.
        // So we can compare if the request changed and if we shall reload 
        // (this also depends on other factors, such as is caching used, etc).
        _lastServerQuery:null,
        
        
        // Store a hash of the last server request. Actually I introduced this
        // for testing, so I can check if no unnecessary requests were issued for
        // client-side-paging.
        lastRequestHash:null,
        
        // If this is false, every request is sent to the server.
        // If it's true a second request with the same query will not issue another
        // request, but use the already returned data. This assumes that the server
        // does not do the paging.
        doClientPaging:true,

        // Items by identify for Identify API
        _itemsByIdentity:null,
        
        // Identifier used
        _identifier:null,

        _features: {'dojo.data.api.Read':true, 'dojo.data.api.Identity':true},
        
        constructor: function(/* Object */ params){
                dojo.mixin(this,params);
        },
        
        getValue: function(/* item */ item, /* attribute-name-string */ attribute, /* value? */ defaultValue){
                //      According to the Read API comments in getValue() and exception is
                //      thrown when an item is not an item or the attribute not a string!
                this._assertIsItem(item);
                if (!dojo.isString(attribute)) {
                        throw new Error(this._className+".getValue(): Invalid attribute, string expected!");
                }
                if(!this.hasAttribute(item, attribute)){
                        // read api says: return defaultValue "only if *item* does not have a value for *attribute*." 
                        // Is this the case here? The attribute doesn't exist, but a defaultValue, sounds reasonable.
                        if(defaultValue){
                                return defaultValue;
                        }
                        console.log(this._className+".getValue(): Item does not have the attribute '"+attribute+"'.");
                }
                return item.i[attribute];
        },
        
        getValues: function(/* item */ item, /* attribute-name-string */ attribute){
                var ret = [];
                if(this.hasAttribute(item, attribute)){
                        ret.push(item.i[attribute]);
                }
                return ret;
        },
        
        getAttributes: function(/* item */ item){
                this._assertIsItem(item);
                var ret = [];
                for(var i in item.i){
                        ret.push(i);
                }
                return ret;
        },

        hasAttribute: function(/* item */ item, /* attribute-name-string */ attribute) {
                //      summary: 
                //              See dojo.data.api.Read.hasAttribute()
                return this.isItem(item) && typeof item.i[attribute]!="undefined";
        },
        
        containsValue: function(/* item */ item, /* attribute-name-string */ attribute, /* anything */ value){
                var values = this.getValues(item, attribute);
                var len = values.length;
                for(var i=0; i<len; i++){
                        if(values[i]==value){
                                return true;
                        }
                }
                return false;
        },
        
        isItem: function(/* anything */ something){
                // Some basic tests, that are quick and easy to do here.
                // >>> var store = new dojox.data.QueryReadStore({});
                // >>> store.isItem("");
                // false
                //
                // >>> var store = new dojox.data.QueryReadStore({});
                // >>> store.isItem({});
                // false
                //
                // >>> var store = new dojox.data.QueryReadStore({});
                // >>> store.isItem(0);
                // false
                //
                // >>> var store = new dojox.data.QueryReadStore({});
                // >>> store.isItem({name:"me", label:"me too"});
                // false
                //
                if(something){
                        return typeof something.r!="undefined" && something.r==this;
                }
                return false;
        },
        
        isItemLoaded: function(/* anything */ something) {
                // Currently we dont have any state that tells if an item is loaded or not
                // if the item exists its also loaded.
                // This might change when we start working with refs inside items ...
                return this.isItem(something);
        },

        loadItem: function(/* object */ args){
                if(this.isItemLoaded(args.item)){
                        return;
                }
                // Actually we have nothing to do here, or at least I dont know what to do here ...
        },

        fetch:function(/* Object? */ request){
                //      summary:
                //              See dojo.data.util.simpleFetch.fetch() this is just a copy and I adjusted
                //              only the paging, since it happens on the server if doClientPaging is
                //              false, thx to http://trac.dojotoolkit.org/ticket/4761 reporting this.
                //              Would be nice to be able to use simpleFetch() to reduce copied code,
                //              but i dont know how yet. Ideas please!
                request = request || {};
                if(!request.store){
                        request.store = this;
                }
                var self = this;
        
                var _errorHandler = function(errorData, requestObject){
                        if(requestObject.onError){
                                var scope = requestObject.scope || dojo.global;
                                requestObject.onError.call(scope, errorData, requestObject);
                        }
                };
        
                var _fetchHandler = function(items, requestObject){
                        var oldAbortFunction = requestObject.abort || null;
                        var aborted = false;
                        
                        var startIndex = requestObject.start?requestObject.start:0;
                        if (self.doClientPaging==false) {
                                // For client paging we dont need no slicing of the result.
                                startIndex = 0;
                        }
                        var endIndex   = requestObject.count?(startIndex + requestObject.count):items.length;
        
                        requestObject.abort = function(){
                                aborted = true;
                                if(oldAbortFunction){
                                        oldAbortFunction.call(requestObject);
                                }
                        };
        
                        var scope = requestObject.scope || dojo.global;
                        if(!requestObject.store){
                                requestObject.store = self;
                        }
                        if(requestObject.onBegin){
                                requestObject.onBegin.call(scope, items.length, requestObject);
                        }
                        if(requestObject.sort){
                                items.sort(dojo.data.util.sorter.createSortFunction(requestObject.sort, self));
                        }
                        if(requestObject.onItem){
                                for(var i = startIndex; (i < items.length) && (i < endIndex); ++i){
                                        var item = items[i];
                                        if(!aborted){
                                                requestObject.onItem.call(scope, item, requestObject);
                                        }
                                }
                        }
                        if(requestObject.onComplete && !aborted){
                                var subset = null;
                                if (!requestObject.onItem) {
                                        subset = items.slice(startIndex, endIndex);
                                }
                                requestObject.onComplete.call(scope, subset, requestObject);   
                        }
                };
                this._fetchItems(request, _fetchHandler, _errorHandler);
                return request; // Object
        },

        getFeatures: function(){
                return this._features;
        },

        close: function(/*dojo.data.api.Request || keywordArgs || null */ request){
                // I have no idea if this is really needed ... 
        },

        getLabel: function(/* item */ item){
                // Override it to return whatever the label shall be, see Read-API.
                return undefined;
        },

        getLabelAttributes: function(/* item */ item){
                return null;
        },
        
        _fetchItems: function(request, fetchHandler, errorHandler){
                //      summary:
                //              The request contains the data as defined in the Read-API.
                //              Additionally there is following keyword "serverQuery".
                //
                //      The *serverQuery* parameter, optional.
                //              This parameter contains the data that will be sent to the server.
                //              If this parameter is not given the parameter "query"'s
                //              data are sent to the server. This is done for some reasons:
                //              - to specify explicitly which data are sent to the server, they
                //                might also be a mix of what is contained in "query", "queryOptions"
                //                and the paging parameters "start" and "count" or may be even
                //                completely different things.
                //              - don't modify the request.query data, so the interface using this
                //                store can rely on unmodified data, as the combobox dijit currently
                //                does it, it compares if the query has changed
                //              - request.query is required by the Read-API
                //
                //              I.e. the following examples might be sent via GET:
                //                fetch({query:{name:"abc"}, queryOptions:{ignoreCase:true}})
                //                the URL will become:   /url.php?name=abc
                //
                //                fetch({serverQuery:{q:"abc", c:true}, query:{name:"abc"}, queryOptions:{ignoreCase:true}})
                //                the URL will become:   /url.php?q=abc&c=true
                //                // The serverQuery-parameter has overruled the query-parameter
                //                // but the query parameter stays untouched, but is not sent to the server!
                //                // The serverQuery contains more data than the query, so they might differ!
                //

                var serverQuery = request.serverQuery || request.query || {};
                //Need to add start and count
                if(!this.doClientPaging){
                        serverQuery.start = request.start || 0;
                        // Count might not be sent if not given.
                        if (request.count) {
                                serverQuery.count = request.count;
                        }
                }
                // Compare the last query and the current query by simply json-encoding them,
                // so we dont have to do any deep object compare ... is there some dojo.areObjectsEqual()???
                if(this.doClientPaging && this._lastServerQuery!==null &&
                        dojo.toJson(serverQuery)==dojo.toJson(this._lastServerQuery)
                        ){
                        fetchHandler(this._items, request);
                }else{
                        var xhrFunc = this.requestMethod.toLowerCase()=="post" ? dojo.xhrPost : dojo.xhrGet;
                        var xhrHandler = xhrFunc({url:this.url, handleAs:"json-comment-optional", content:serverQuery});
                        xhrHandler.addCallback(dojo.hitch(this, function(data){
                                data=this._filterResponse(data);
                                this._items = [];
                                // Store a ref to "this" in each item, so we can simply check if an item
                                // really origins form here (idea is from ItemFileReadStore, I just don't know
                                // how efficient the real storage use, garbage collection effort, etc. is).
                                dojo.forEach(data.items,function(e){ 
                                        this._items.push({i:e, r:this}); 
                                },this); 
                                
                                var identifier = data.identifier;
                                this._itemsByIdentity = {};
                                if(identifier){
                                        this._identifier = identifier;
                                        for(i = 0; i < this._items.length; ++i){
                                                var item = this._items[i].i;
                                                var identity = item[identifier];
                                                if(!this._itemsByIdentity[identity]){
                                                        this._itemsByIdentity[identity] = item;
                                                }else{
                                                        throw new Error("dojo.data.QueryReadStore:  The json data as specified by: [" + this.url + "] is malformed.  Items within the list have identifier: [" + identifier + "].  Value collided: [" + identity + "]");
                                                }
                                        }
                                }else{
                                        this._identifier = Number;
                                        for(i = 0; i < this._items.length; ++i){
                                                this._items[i].n = i;
                                        }
                                }
                                
                                // TODO actually we should do the same as dojo.data.ItemFileReadStore._getItemsFromLoadedData() to sanitize
                                // (does it really sanititze them) and store the data optimal. should we? for security reasons???
                                fetchHandler(this._items, request);
                        }));
                        xhrHandler.addErrback(function(error){
                                errorHandler(error, request);
                        });
                        // Generate the hash using the time in milliseconds and a randon number.
                        // Since Math.randon() returns something like: 0.23453463, we just remove the "0."
                        // probably just for esthetic reasons :-).
                        this.lastRequestHash = new Date().getTime()+"-"+String(Math.random()).substring(2);
                        this._lastServerQuery = dojo.mixin({}, serverQuery);
                }
        },
        
        _filterResponse: function(data){
                //      summary:
                //              If the data from servers needs to be processed before it can be processed by this
                //              store, then this function should be re-implemented in subclass. This default 
                //              implementation just return the data unchanged.
                //      data:
                //              The data received from server
                return data;
        },

        _assertIsItem: function(/* item */ item){
                //      summary:
                //              It throws an error if item is not valid, so you can call it in every method that needs to
                //              throw an error when item is invalid.
                //      item: 
                //              The item to test for being contained by the store.
                if(!this.isItem(item)){
                        throw new dojox.data.QueryReadStore.InvalidItemError(this._className+": a function was passed an item argument that was not an item");
                }
        },

        _assertIsAttribute: function(/* attribute-name-string */ attribute){
                //      summary:
                //              This function tests whether the item passed in is indeed a valid 'attribute' like type for the store.
                //      attribute: 
                //              The attribute to test for being contained by the store.
                if(typeof attribute !== "string"){ 
                        throw new dojox.data.QueryReadStore.InvalidAttributeError(this._className+": '"+attribute+"' is not a valid attribute identifier.");
                }
        },

        fetchItemByIdentity: function(/* Object */ keywordArgs){
                //      summary: 
                //              See dojo.data.api.Identity.fetchItemByIdentity()

                // See if we have already loaded the item with that id
                // In case there hasn't been a fetch yet, _itemsByIdentity is null
                // and thus a fetch will be triggered below.
                if(this._itemsByIdentity){
                        var item = this._itemsByIdentity[keywordArgs.identity];
                        if(!(item === undefined)){
                                if(keywordArgs.onItem){
                                        var scope =  keywordArgs.scope?keywordArgs.scope:dojo.global;
                                        keywordArgs.onItem.call(scope, {i:item, r:this});
                                }
                                return;
                        }
                }

                // Otherwise we need to go remote
                // Set up error handler
                var _errorHandler = function(errorData, requestObject){
                        var scope =  keywordArgs.scope?keywordArgs.scope:dojo.global;
                        if(keywordArgs.onError){
                                keywordArgs.onError.call(scope, error);
                        }
                };
                
                // Set up fetch handler
                var _fetchHandler = function(items, requestObject){
                        var scope =  keywordArgs.scope?keywordArgs.scope:dojo.global;
                        try{
                                // There is supposed to be only one result
                                var item = null;
                                if(items && items.length == 1){
                                        item = items[0];
                                }
                                
                                // If no item was found, item is still null and we'll
                                // fire the onItem event with the null here
                                if(keywordArgs.onItem){
                                        keywordArgs.onItem.call(scope, item);
                                }
                        }catch(error){
                                if(keywordArgs.onError){
                                        keywordArgs.onError.call(scope, error);
                                }
                        }
                };
                
                // Construct query
                var request = {serverQuery:{id:keywordArgs.identity}};
                
                // Dispatch query
                this._fetchItems(request, _fetchHandler, _errorHandler);
        },
        
        getIdentity: function(/* item */ item){
                //      summary: 
                //              See dojo.data.api.Identity.getIdentity()
                var identifier = null;
                if(this._identifier === Number){
                        identifier = item.n; // Number
                }else{
                        identifier = item.i[this._identifier];
                }
                return identifier;
        },
        
        getIdentityAttributes: function(/* item */ item){
                //      summary:
                //              See dojo.data.api.Identity.getIdentityAttributes()
                return [this._identifier];
        }
});

dojo.declare("dojox.data.QueryReadStore.InvalidItemError", Error, {});
dojo.declare("dojox.data.QueryReadStore.InvalidAttributeError", Error, {});




}