offline-editor-js/lib/edit/editStorePOLS.js
2016-05-11 12:58:42 -06:00

472 lines
17 KiB
JavaScript

/*global indexedDB */
/*jshint -W030 */
/**
* This library is optimized for Partial Offline Support ONLY
* @constructor
*/
O.esri.Edit.EditStorePOLS = function () {
"use strict";
this._db = null;
this._isDBInit = false;
// Public properties
this.dbName = "features_store";
this.objectStoreName = "features";
this.objectId = "objectid"; // set this depending on how your feature service is configured;
//var _dbIndex = "featureId"; // @private
// ENUMs
this.ADD = "add";
this.UPDATE = "update";
this.DELETE = "delete";
this.FEATURE_LAYER_JSON_ID = "feature-layer-object-1001";
this.FEATURE_COLLECTION_ID = "feature-collection-object-1001";
this.isSupported = function () {
if (!window.indexedDB) {
return false;
}
return true;
};
/**
* Commit an edit to the database
* @param operation add, update or delete
* @param layerUrl the URL of the feature layer
* @param graphic esri/graphic. The method will serialize to JSON
* @param callback callback(true, edit) or callback(false, error)
*/
this.pushEdit = function (operation, layerUrl, graphic, callback) {
var edit = {
id: layerUrl + "/" + graphic.attributes[this.objectId],
operation: operation,
layer: layerUrl,
type: graphic.geometry.type,
graphic: graphic.toJson()
};
if(typeof graphic.attributes[this.objectId] === "undefined") {
console.error("editsStore.pushEdit() - failed to insert undefined objectId into database. Did you set offlineEdit.DB_UID? " + JSON.stringify(graphic.attributes));
callback(false,"editsStore.pushEdit() - failed to insert undefined objectId into database. Did you set offlineEdit.DB_UID? " + JSON.stringify(graphic.attributes));
}
else{
var transaction = this._db.transaction([this.objectStoreName], "readwrite");
transaction.oncomplete = function (event) {
callback(true);
};
transaction.onerror = function (event) {
callback(false, event.target.error.message);
};
var objectStore = transaction.objectStore(this.objectStoreName);
objectStore.put(edit);
}
};
/**
* Retrieve an edit by its internal ID
* @param id String identifier
* @param callback callback(true,graphic) or callback(false, error)
*/
this.getEdit = function(id,callback){
console.assert(this._db !== null, "indexeddb not initialized");
var objectStore = this._db.transaction([this.objectStoreName], "readwrite").objectStore(this.objectStoreName);
if(typeof id === "undefined"){
callback(false,"id is undefined.");
return;
}
//Get the entry associated with the graphic
var objectStoreGraphicRequest = objectStore.get(id);
objectStoreGraphicRequest.onsuccess = function () {
var graphic = objectStoreGraphicRequest.result;
if (graphic && (graphic.id == id)) {
callback(true,graphic);
}
else {
callback(false,"Id not found");
}
};
objectStoreGraphicRequest.onerror = function (msg) {
callback(false,msg);
};
};
/**
* Returns all the edits as a single Array via the callback
* @param callback {array, messageString} or {null, messageString}
*/
this.getAllEditsArray = function (callback) {
console.assert(this._db !== null, "indexeddb not initialized");
var editsArray = [];
if (this._db !== null) {
var fLayerJSONId = this.FEATURE_LAYER_JSON_ID;
var fCollectionId = this.FEATURE_COLLECTION_ID;
var transaction = this._db.transaction([this.objectStoreName])
.objectStore(this.objectStoreName)
.openCursor();
transaction.onsuccess = function (event) {
var cursor = event.target.result;
if (cursor && cursor.value && cursor.value.id) {
// Make sure we are not return FeatureLayer JSON data
if (cursor.value.id !== fLayerJSONId && cursor.value.id !== fCollectionId) {
editsArray.push(cursor.value);
}
cursor.continue();
}
else {
callback(editsArray, "end");
}
}.bind(this);
transaction.onerror = function (err) {
callback(null, err);
};
}
else {
callback(null, "no db");
}
};
/*
* Query the database, looking for any existing Add temporary OIDs, and return the nextTempId to be used.
* @param feature - extended layer from offline edit advanced
* @param callback {int, messageString} or {null, messageString}
*/
this.getNextLowestTempId = function (feature, callback) {
var addOIDsArray = [],
self = this;
if (this._db !== null) {
var fLayerJSONId = this.FEATURE_LAYER_JSON_ID;
var fCollectionId = this.FEATURE_COLLECTION_ID;
var transaction = this._db.transaction([this.objectStoreName])
.objectStore(this.objectStoreName)
.openCursor();
transaction.onsuccess = function (event) {
var cursor = event.target.result;
if (cursor && cursor.value && cursor.value.id) {
// Make sure we are not return FeatureLayer JSON data or a Phantom Graphic
if (cursor.value.id !== fLayerJSONId && cursor.value.id !== fCollectionId) {
if(cursor.value.layer === feature.url && cursor.value.operation === "add"){ // check to make sure the edit is for the feature we are looking for, and that the operation is an add.
addOIDsArray.push(cursor.value.graphic.attributes[self.objectId]); // add the temporary OID to the array
}
}
cursor.continue();
}
else {
if(addOIDsArray.length === 0){ // if we didn't find anything,
callback(-1, "success"); // we'll start with -1
}
else{
var filteredOIDsArray = addOIDsArray.filter(function(val){ // filter out any non numbers from the array...
return !isNaN(val); // .. should anything have snuck in or returned a NaN
});
var lowestTempId = Math.min.apply(Math, filteredOIDsArray); // then find the lowest number from the array
callback(lowestTempId-1, "success"); // and we'll start with one less than tat.
}
}
}.bind(this);
transaction.onerror = function (err) {
callback(null, err);
};
}
else {
callback(null, "no db");
}
};
/**
* Update an edit already exists in the database
* @param operation add, update or delete
* @param layer the URL of the feature layer
* @param graphic esri/graphic. The method will serialize to JSON
* @param callback {true, edit} or {false, error}
*/
this.updateExistingEdit = function (operation, layer, graphic, callback) {
console.assert(this._db !== null, "indexeddb not initialized");
var objectStore = this._db.transaction([this.objectStoreName], "readwrite").objectStore(this.objectStoreName);
//Let's get the entry associated with the graphic
var objectStoreGraphicRequest = objectStore.get(graphic.attributes[this.objectId]);
objectStoreGraphicRequest.onsuccess = function () {
//Grab the data object returned as a result
// TO-DO Do we keep this??
objectStoreGraphicRequest.result;
//Create a new update object
var update = {
id: layer + "/" + graphic.attributes[this.objectId],
operation: operation,
layer: layer,
graphic: graphic.toJson()
};
// Insert the update into the database
var updateGraphicRequest = objectStore.put(update);
updateGraphicRequest.onsuccess = function () {
callback(true);
};
updateGraphicRequest.onerror = function (err) {
callback(false, err);
};
}.bind(this);
};
/**
* Delete a pending edit's record from the database.
* IMPORTANT: Be aware of false negatives. See Step 4 in this function.
*
* @param layerUrl
* @param graphic Graphic
* @param callback {boolean, error}
*/
this.delete = function (layerUrl, graphic, callback) {
// NOTE: the implementation of the IndexedDB spec has a design fault with respect to
// handling deletes. The result of a delete operation is always designated as undefined.
// What this means is that there is no way to tell if an operation was successful or not.
// And, it will always return 'true.'
//
// In order to get around this we have to verify if after the attempted deletion operation
// if the record is or is not in the database. Kinda dumb, but that's how IndexedDB works.
//http://stackoverflow.com/questions/17137879/is-there-a-way-to-get-information-on-deleted-record-when-calling-indexeddbs-obj
var db = this._db;
var deferred = null;
var self = this;
var id = layerUrl + "/" + graphic.attributes[this.objectId];
require(["dojo/Deferred"], function (Deferred) {
deferred = new Deferred();
// Step 1 - lets see if record exits. If it does then return callback.
self.editExists(id).then(function (result) {
// Step 4 - Then we check to see if the record actually exists or not.
deferred.then(function (result) {
// IF the delete was successful, then the record should return 'false' because it doesn't exist.
self.editExists(id).then(function (results) {
callback(false);
},
function (err) {
callback(true); //because we want this test to throw an error. That means item deleted.
});
},
// There was a problem with the delete operation on the database
function (err) {
callback(false, err);
});
var objectStore = db.transaction([self.objectStoreName], "readwrite").objectStore(self.objectStoreName);
// Step 2 - go ahead and delete graphic
var objectStoreDeleteRequest = objectStore.delete(id);
// Step 3 - We know that the onsuccess will always fire unless something serious goes wrong.
// So we go ahead and resolve the deferred here.
objectStoreDeleteRequest.onsuccess = function () {
deferred.resolve(true);
};
objectStoreDeleteRequest.onerror = function (msg) {
deferred.reject({success: false, error: msg});
};
},
// If there is an error in editExists()
function (err) {
callback(false, err);
});
});
};
/**
* Full database reset.
* CAUTION! If some edits weren't successfully sent, then their record
* will still exist in the database. If you use this function you
* will also delete those records.
* @param callback boolean
*/
this.resetEditsQueue = function (callback) {
console.assert(this._db !== null, "indexeddb not initialized");
var request = this._db.transaction([this.objectStoreName], "readwrite")
.objectStore(this.objectStoreName)
.clear();
request.onsuccess = function (event) {
setTimeout(function () {
callback(true);
}, 0);
};
request.onerror = function (err) {
callback(false, err);
};
};
this.pendingEditsCount = function (callback) {
console.assert(this._db !== null, "indexeddb not initialized");
var count = 0;
var id = this.FEATURE_LAYER_JSON_ID;
var fCollectionId = this.FEATURE_COLLECTION_ID;
var transaction = this._db.transaction([this.objectStoreName], "readwrite");
var objectStore = transaction.objectStore(this.objectStoreName);
objectStore.openCursor().onsuccess = function (evt) {
var cursor = evt.target.result;
if (cursor && cursor.value && cursor.value.id) {
if (cursor.value.id !== id && cursor.value.id !== fCollectionId) {
count++;
}
cursor.continue();
}
else {
callback(count);
}
};
};
/**
* Verify is an edit already exists in the database. Checks the objectId.
* @param id
* @returns {deferred} {success: boolean, error: message}
* @private
*/
this.editExists = function (id) {
var db = this._db;
var deferred = null;
var self = this;
require(["dojo/Deferred"], function (Deferred) {
deferred = new Deferred();
var objectStore = db.transaction([self.objectStoreName], "readwrite").objectStore(self.objectStoreName);
//Get the entry associated with the graphic
var objectStoreGraphicRequest = objectStore.get(id);
objectStoreGraphicRequest.onsuccess = function () {
var graphic = objectStoreGraphicRequest.result;
if (graphic && (graphic.id == id)) {
deferred.resolve({success: true, error: null});
}
else {
deferred.reject({success: false, error: "objectId is not a match."});
}
};
objectStoreGraphicRequest.onerror = function (msg) {
deferred.reject({success: false, error: msg});
};
});
//We return a deferred object so that when calling this function you can chain it with a then() statement.
return deferred;
};
/**
* Returns the approximate size of the database in bytes
* IMPORTANT: Currently requires all data be serialized!
* @param callback callback({usage}, error) Whereas, the usage Object is {sizeBytes: number, editCount: number}
*/
this.getUsage = function (callback) {
console.assert(this._db !== null, "indexeddb not initialized");
var id = this.FEATURE_LAYER_JSON_ID;
var fCollectionId = this.FEATURE_COLLECTION_ID;
var usage = {sizeBytes: 0, editCount: 0};
var transaction = this._db.transaction([this.objectStoreName])
.objectStore(this.objectStoreName)
.openCursor();
console.log("dumping keys");
transaction.onsuccess = function (event) {
var cursor = event.target.result;
if (cursor && cursor.value && cursor.value.id) {
var storedObject = cursor.value;
var json = JSON.stringify(storedObject);
usage.sizeBytes += json.length;
if (cursor.value.id !== id && cursor.value.id !== fCollectionId) {
usage.editCount += 1;
}
cursor.continue();
}
else {
callback(usage, null);
}
};
transaction.onerror = function (err) {
callback(null, err);
};
};
this.init = function (callback) {
console.log("init editsStore.js");
var request = indexedDB.open(this.dbName, 11);
callback = callback || function (success) {
console.log("EditsStore::init() success:", success);
}.bind(this);
request.onerror = function (event) {
console.log("indexedDB error: " + event.target.errorCode);
callback(false, event.target.errorCode);
}.bind(this);
request.onupgradeneeded = function (event) {
var db = event.target.result;
if (db.objectStoreNames.contains(this.objectStoreName)) {
db.deleteObjectStore(this.objectStoreName);
}
db.createObjectStore(this.objectStoreName, {keyPath: "id"});
}.bind(this);
request.onsuccess = function (event) {
this._db = event.target.result;
this._isDBInit = true;
console.log("database opened successfully");
callback(true, null);
}.bind(this);
};
};