IndexedDB - असीमित डेटा भंडारण

पोस्टिंग साइट-एक्सटेंशन-साइट

 "externally_connectable": { "matches": [ "*://localhost/*", "____URL " ] } 

विस्तार

 var server; chrome.runtime.onMessageExternal.addListener( function (request, sender, sendResponse) { var cmd = request.cmd, params = request.params; try { switch (cmd) { case "getUsageAndQuota": navigator.webkitPersistentStorage.queryUsageAndQuota(function(u,q){ sendResponse({"usage": u,"quota":q}); }); break; case "open": db.open(params).done(function (s) { server = s; var exclude = "add close get query remove update".split(" "); var tables = new Array(); for(var table in server){ if(exclude.indexOf(table)==-1){ tables.push(table); } } sendResponse(tables); }); break; case "close": server.close(); sendResponse({}); break; case "get": server[request.table].get(params).done(sendResponse) break; case "add": server[request.table].add(params).done(sendResponse); break; case "update": server[request.table].update(params).done(sendResponse); break; case "remove": server[request.table].remove(params).done(sendResponse); break; case "execute": var tmp_server = server[request.table]; var query = tmp_server.query.apply(tmp_server, obj2arr(request.query)); var flt; for (var i = 0; i < request.filters.length; i++) { flt = request.filters[i]; if (flt.type == "filter") { flt.args = new Function("item", flt.args[0]); } query = query[flt.type].apply(query, obj2arr(flt.args)); } query.execute().done(sendResponse); break; } } catch (error) { if (error.name != "TypeError") { sendResponse({RUNTIME_ERROR: error}); } } return true; }); 

 flt.args = new Function("item", flt.args[0]); 

 "content_security_policy": "script-src 'self' 'unsafe-eval'; object-src 'self'" 

 var obj2arr = function (obj) { if (typeof obj == 'object') { var tmp_args = new Array(); for (var k in obj) { tmp_args.push(obj[k]); } return tmp_args; } else { return [obj]; } } 

 { "manifest_version": 2, "name": "exDB", "description": "This extension give proxy access to indexdb from page.", "version": "1.0", "background": { "page": "background.html" }, "content_security_policy": "script-src 'self' 'unsafe-eval'; object-src 'self'", "externally_connectable": { "matches": [ "*://localhost/*" ] }, "permissions": [ "unlimitedStorage", "unlimited_storage" ], "icons": { "16": "icons/icon_016.png", "48": "icons/icon_048.png" } } 

ग्राहक

 chrome.runtime.sendMessage("ID_", data, callback); 

 (function (window, undefined) { "use strict"; function exDB() { var self = this; this.extensionId = arguments[0] || "eojllnbjkomphhmpcpafaipblnembfem"; this.filterList = new Array(); this._table; this._query; self.sendMessage = function sendMessage(data, callback) { chrome.runtime.sendMessage(self.extensionId, data, callback); }; self.open = function (params, callback) { self.sendMessage({"cmd": "open", "params": params}, function(r){ var tn; for(var i=0;i< r.length;i++) tn = r[i]; self.__defineGetter__(tn,function(){ self._table = tn; return this; }); callback(); }); return self; }; self.close = function (callback) { self.sendMessage({"cmd": "close", "params": {}}, callback); return self; } self.table = function (name) { self._table = name; return self; }; self.query = function () { self._query = arguments; return self; }; self.execute = function (callback) { self.sendMessage({"cmd": "execute", "table": self._table, "query": self._query, "filters": self.filterList}, function (result) { if (result && result.RUNTIME_ERROR) { console.error(result.RUNTIME_ERROR.message); result = null; } callback(result); }); self._query = null; self.filterList = []; }; self.getUsageAndQuota = function(callback){ self.sendMessage({"cmd": "getUsageAndQuota"},callback); }; "add update remove get".split(" ").forEach(function (fn) { self[fn] = function (item, callback) { self.sendMessage({"cmd": fn, "table": self._table, "params": item}, function (result) { if (result && result.RUNTIME_ERROR) { console.error(result.RUNTIME_ERROR.message); result = null; } callback(result); }); return self; } }); "all only lowerBound upperBound bound filter desc distinct keys count".split(" ").forEach(function (fn) { self[fn] = function () { self.filterList.push({type: fn, args: arguments}); return self; } }); } window.exDB = exDB; })(window, undefined); 

संबंध

  var db = new exDB(); db.open({ server: 'my-app', version: 1, schema: { people: { key: { keyPath: 'id', autoIncrement: true }, // Optionally add indexes indexes: { firstName: { }, answer: { unique: true } } } } }, function () {}); 

कनेक्शन बंद करें

 db.close(); 

रिकॉर्ड जोड़ें

 db.table("people").add({ firstName: 'Aaron', lastName: 'Powell', answer: 142},function(r){ }); 

रिकॉर्ड अपडेट करें

  db.table("people").update({ id:1, firstName: 'Aaron', lastName: 'Powell', answer: 1242}, function (r) {}); 

आईडी द्वारा रिकॉर्ड हटाएं

 db.table("people").remove(1,function(key){}); 

आईडी द्वारा रिकॉर्ड प्राप्त करना

 db.table("people").get(1,function(r){ console.log(r); }); 

ले आओ / छाँटो

 db.people.query("firstName").only("Aaron2").execute(function(r){ console.log("GETTER",r); }); db.table("people").query("answer").all().desc().execute(function(r){ console.log("all",r); }); db.table("people").query("answer").only(12642).count().execute(function(r){ console.log("only",r); }); db.table("people").query("answer").bound(20,45).execute(function(r){ console.log("bound",r); }); db.table("people").query("answer").lowerBound(50).keys().execute(function(r){ console.log("lowerBound",r); }); db.table("people").query("answer").upperBound(43).execute(function(r){ console.log("upperBound",r); }); db.table("people").query("answer").filter("return item.answer==42 && item.firstName=='Aaron'").execute(function(r){ console.log("filter",r); }); 

डेटाबेस का आकार प्राप्त करना (प्रयुक्त / अधिकतम आकार)

 db.getUsageAndQuota(function(r){ console.log("used", r.usage); //bytes console.log("quota", r.quota); //bytes }); 

निष्कर्ष