offline-editor-js/lib/edit/offlineFeaturesManager.js
2014-02-03 11:04:29 +01:00

302 lines
9.1 KiB
JavaScript

"use strict";
define([
"edit/editsStore",
"vendor/offline/offline.min",
"dojo/Evented",
"dojo/_base/Deferred",
"dojo/promise/all",
"dojo/_base/declare",
"dojo/_base/lang",
"esri/request"],
function(editsStore,Offline,Evented,Deferred,all,declare,lang,esriRequest)
{
return declare([Evented],
{
_onlineStatus: "online",
_featureLayers: {},
ONLINE: "online", // all edits will directly go to the server
OFFLINE: "offline", // edits will be enqueued
RECONNECTING: "reconnecting", // sending stored edits to the server
// manager emits event when...
events: {
EDITS_SENT: 'edits-sent', // ...whenever any edit is actually sent to the server
EDITS_ENQUEUED: 'edits-enqueued', // ...when an edit is enqueued (and not sent to the server)
ALL_EDITS_SENT: 'all-edits-sent' // ...after going online and there are no pending edits in the queue
},
extend: function(layer)
{
var self = this;
// we keep track of the FeatureLayer object
this._featureLayers[ layer.url ] = layer;
/* replace the applyEdits() method */
layer._applyEdits = layer.applyEdits;
layer.applyEdits = function(adds,updates,deletes,callback,errback)
{
// inside this method, 'this' will be the FeatureLayer
// and 'self' will be the offlineFeatureLayer object
if( self.getOnlineStatus() == self.ONLINE)
{
var def = layer._applyEdits(adds,updates,deletes,
function()
{
self.emit(self.events.EDITS_SENT,arguments);
callback && callback.apply(this,arguments);
},
errback);
return def;
}
else
{
var deferred = new Deferred();
var results = { addResults:[],updateResults:[], deleteResults:[] };
var updatesMap = {};
this.onBeforeApplyEdits(adds, updates, deletes);
adds = adds || [];
adds.forEach(function(addEdit)
{
var objectId = this.getNextTempId();
addEdit.attributes[ this.objectIdField ] = objectId;
var success = editsStore.pushEdit(editsStore.ADD, this.url, addEdit);
results.addResults.push({ success:success, objectId: objectId});
},this);
updates = updates || [];
updates.forEach(function(updateEdit)
{
var objectId = updateEdit.attributes[ this.objectIdField ];
var success = editsStore.pushEdit(editsStore.UPDATE, this.url, updateEdit);
results.updateResults.push({success:success, objectId: objectId});
updatesMap[ objectId ] = updateEdit;
},this);
deletes = deletes || [];
deletes.forEach(function(deleteEdit)
{
var success = editsStore.pushEdit(editsStore.DELETE, this.url, deleteEdit);
results.deleteResults.push({success:success, objectId: deleteEdit.attributes[ this.objectIdField ]});
},this);
/* we already pushed the edits into the local store, now we let the FeatureLayer to do the local updating of the layer graphics */
this._editHandler(results, adds, updatesMap, callback, errback, deferred);
self.emit(self.events.EDITS_ENQUEUED, results);
return deferred;
}
}; // layer.applyEdits()
// we need to identify ADDs before sending them to the server
// we assign temporary ids (using negative numbers to distinguish them from real ids)
layer._nextTempId = -1;
layer.getNextTempId = function()
{
return this._nextTempId--;
};
}, // extend
goOffline: function()
{
console.log('going offline');
this._onlineStatus = this.OFFLINE;
},
goOnline: function(callback)
{
console.log('going online');
this._onlineStatus = this.RECONNECTING;
this.replayStoredEdits(function()
{
this._onlineStatus = this.ONLINE;
callback && callback.apply(this,arguments);
}.bind(this));
//this.refresh();
},
getOnlineStatus: function()
{
return this._onlineStatus;
},
optimizeEditsQueue: function()
{
// console.log("edits:", editsStore._retrieveEditsQueue().map(function(e){return this.getReadableEdit(e)},this));
var optimizedEdits = {};
var editCount = editsStore.pendingEditsCount();
var optimizedCount = 0;
while( editsStore.hasPendingEdits() )
{
var edit = editsStore.popFirstEdit();
var layer = this._featureLayers[ edit.layer ];
if( ! (edit.layer in optimizedEdits) )
optimizedEdits[edit.layer] = {}
var layerEdits = optimizedEdits[edit.layer];
var objectId = edit.graphic.attributes[ layer.objectIdField ];
if( !( objectId in layerEdits) )
{
// first edit we see of this feature, no optimization to apply
layerEdits[ objectId ] = edit;
optimizedCount += 1;
}
else
{
// we already have seen one edit for this same feature... we can merge the two edits in a single operation
switch( edit.operation )
{
case editsStore.ADD:
/* impossible!! */
throw("can't add the same feature twice!");
break;
case editsStore.UPDATE:
layerEdits[ objectId ].graphic = edit.graphic;
break;
case editsStore.DELETE:
if(objectId < 0)
delete layerEdits[ objectId ];
else
layerEdits[objectId].operation = editsStore.DELETE;
break;
}
}
}
// console.log("optimized:",optimizedEdits);
console.log("optimized", editCount, "edits into", optimizedCount,"edits of", Object.keys(optimizedEdits).length ,"layers");
return optimizedEdits;
},
replayStoredEdits: function(callback)
{
if( editsStore.hasPendingEdits() )
{
//
// flatten the queue into unique edits for each feature, grouped by FeatureLayer
//
var optimizedEdits = this.optimizeEditsQueue();
var promises = {};
//
// send edits for each of the layers
//
for(var layerUrl in optimizedEdits)
{
if(!optimizedEdits.hasOwnProperty(layerUrl))
continue;
var layer = this._featureLayers[ layerUrl ];
var layerEdits = optimizedEdits[layerUrl];
layer.__onEditsComplete = layer["onEditsComplete"];
layer["onEditsComplete"] = function() { console.log("intercepting events onEditsComplete");}
layer.__onBeforeApplyEdits = layer["onBeforeApplyEdits"];
layer["onBeforeApplyEdits"] = function() { console.log("intercepting events onBeforeApplyEdits");}
var adds = [], updates = [], deletes = [];
for(var objectId in layerEdits)
{
if(!layerEdits.hasOwnProperty(objectId))
continue;
var edit = layerEdits[objectId];
switch(edit.operation)
{
case editsStore.ADD:
for(var i=0; i<layer.graphics.length; i++)
{
var g = layer.graphics[i];
if( g.attributes[layer.objectIdField] == edit.graphic.attributes[layer.objectIdField] )
{
layer.remove(g);
break;
}
};
delete edit.graphic.attributes[ layer.objectIdField ];
adds.push(edit.graphic);
break;
case editsStore.UPDATE:
updates.push(edit.graphic);
break;
case editsStore.DELETE:
deletes.push(edit.graphic)
break;
}
}
promises[layerUrl] = function(layer)
{
// unfortunately we can't use the promise that is returned from layer._applyEdits()
// because it returns 3 result parameters (addResults,updateResults,deleteResults)
// and when we combine all promises in the dojo/promise/all() method below this only
// supports promises that return one value
var dfd = new Deferred();
layer._applyEdits(adds,updates,deletes,
function(addResults,updateResults,deleteResults)
{
layer["onEditsComplete"] = layer.__onEditsComplete; delete layer.__onEditsComplete;
layer["onBeforeApplyEdits"] = layer.__onBeforeApplyEdits; delete layer.__onBeforeApplyEdits;
dfd.resolve({addResults:addResults,updateResults:updateResults,deleteResults:deleteResults}); // wrap three arguments in a single object
},
function(error)
{
layer["onEditsComplete"] = layer.__onEditsComplete; delete layer.__onEditsComplete;
layer["onBeforeApplyEdits"] = layer.__onBeforeApplyEdits; delete layer.__onBeforeApplyEdits;
dfd.reject(error);
}
);
return dfd;
}(layer);
}
//
// wait for all requests to finish
//
var allPromises = new all(promises);
allPromises.then(
function(responses)
{
console.log("all responses are back");
this.emit(this.events.EDITS_SENT);
this.emit(this.events.ALL_EDITS_SENT);
callback && callback(true,responses);
}.bind(this),
function(errors)
{
console.log("ERROR!!");
console.log(errors);
callback && callback(false,errors);
}.bind(this));
} // hasPendingEdits()
else
{
this.emit(this.events.ALL_EDITS_SENT);
callback && callback(true, {});
}
},
getReadableEdit: function(edit)
{
var layer = this._featureLayers[ edit.layer ];
var graphic = editsStore._deserialize(edit.graphic);
var readableGraphic = graphic.geometry.type;
var layerId = edit.layer.substring(edit.layer.lastIndexOf('/')+1);
if(layer)
readableGraphic += " [id=" + graphic.attributes[layer.objectIdField] + "]";
return "o:" + edit.operation + ", l:" + layerId + ", g:" + readableGraphic;
},
}); // declare
}); // define