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  • Should I be using a JavaScript SPA designed when security is important

    - by ryanzec
    I asked something kind of similar on stackoverflow with a particular piece of code however I want to try to ask this in a broader sense. So I have this web application that I have started to write in backbone using a Single Page Architecture (SPA) however I am starting to second guess myself because of security. Now we are not storing and sending credit card information or anything like that through this web application but we are storing sensitive information that people are uploading to us and will have the ability to re-download too. The obviously security concern that I have with JavaScript is that you can't trust anything that comes from JavaScript however in a Backbone SPA application, everything is being sent through JavaScript. There are two security features that I will have to build in JavaScript; permissions and authentication. The authentication piece is just me override the Backbone.Router.prototype.navigate method to check the fragment it is trying to load and if the JavaScript application.session.loggedIn is not set to true (and they are not viewing a none authenticated page), they are redirected to the login page automatically. The user could easily modify application.session.loggedIn to equal true (or modify Backbone.Router.prototype.navigate method) but then they would also have to not so easily dynamically embedded a link into the page (or modify a current one) that has the proper classes, data-* attributes, and href values to then load a page that should only be loaded when they user has logged in (and has the permissions). So I have an acl object that deals with the permissions stuff. All someone would have to do to view pages or parts of pages they should not be able to is to call acl.addPermission(resource, permission) with the proper permissions or modify the acl.hasPermission() to always return true and then navigate away and then back to the page. Now certain things is EMCAScript 5 like Object.seal() or Object.freeze() would help with some of this however we have to support IE 8 which does not support those pieces of functionality. Now the REST API also performs security checks on every request so technically even if they are able to see parts of the interface that they should not be able to, they still should not be able to actually affect any data. The main benefits for me in developing a JavaScript SPA application is that the application is a lot more responsive since it is only transferring the minimum amount of JSON data for the requested action and performing the minimum amount of work too. There are also other things that I think are beneficial like you are going to have to develop an API for the data (which is good if you want expand your application to different platforms/technologies) or their is more of a separation between front-end and back-end however if security is a concern, it is really wise to go down the road of a JavaScript SPA application for the front-end?

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  • Impressions from VMworld - Clearing up Misconceptions

    - by Monica Kumar
    Gorgeous sunny weather…none of the usual summer fog…the Oracle Virtualization team has been busy at VMworld in San Francisco this week. From the time exhibits opened on Sunday, our booth staff was fully engaged with visitors. It was great to meet with customers and prospects, and there were many…most with promises to meet again in October at Oracle OpenWorld 2012. Interests and questions ran the gamut - from implementation details to consolidating applications to how does Oracle VM enable rapid application deployment to Oracle support and licensing. All good stuff! Some inquiries are poignant and really help us get at the customer pain points. Some are just based on misconceptions. We’d like to address a couple of common misconceptions that we heard: 1) Rapid deployment of enterprise applications is great but I don’t do this all the time. So why bother? While production applications don’t get updated or upgraded as often, development and QA staging environments are much more dynamic. Also, in today’s Cloud based computing environments, end users expect an entire solution, along with the virtual machine, to be provisioned instantly, on-demand, as and when they need to scale. Whether it’s adding a new feature to meet customer demands or updating applications to meet business/service compliance, these environments undergo change frequently. The ability to rapidly stand up an entire application stack with all the components such as database tier, mid-tier, OS, and applications tightly integrated, can offer significant value. Hand patching, installation of the OS, application and configurations to ensure the entire stack works well together can take days and weeks. Oracle VM Templates provide a much faster path to standing up a development, QA or production stack in a matter of hours or minutes. I see lots of eyes light up as we get to this point of the conversation. 2) Oracle Software licensing on VMware vSphere In the world of multi-vendor IT stacks, understanding license boundaries and terms and conditions for each product in the stack can be challenging.  Oracle’s licensing, though, is straightforward.  Oracle software is licensed per physical processor in the server or cluster where the Oracle software is installed and/or running.  The use of third party virtualization technologies such as VMware is not allowed as a means to change the way Oracle software is licensed.  Exceptions are spelled out in the licensing document labeled “Hard Partitioning". Here are some fun pictures! Visitors to our booth told us they loved the Oracle SUV courtesy shuttles that are helping attendees get to/from hotels. Also spotted were several taxicabs sporting an Oracle banner! Stay tuned for more highlights across desktop and server virtualization as we wrap up our participation at VMworld.

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  • Javascript in XSL that is loaded by Javascript

    - by James Armstead
    Is there anyway to have javascript run when a XSL sheet has been applied to an XML file by Javascript? I am using a JQuery plugin to apply the sheet to the xml but the javascript that is located inside of the XSL file will not run. I put the Javascript at the bottom of the file and it still does not run.. I can't seem to get an alert to even run?

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  • using javascript onchange to fill a calendar

    - by scatman
    i have a calendar and a textbox in my c# asp.net application. when a user enters a date in the textbox, the selected date in the calendar should become the date entered in the text box. the hard part is that i need to do this in javascript. what i have now is this: <asp:TextBox ID="txtDate" runat="server" onchange="javascript: Changed( this );" /> <asp:Calendar ID="calDate" runat="server" /> <script type="text/javascript"> var calendarID = ''; function Changed(textControl) { var date = Date.parse(textControl.value); //this is giving me the date in seconds var cal = document.getElementById(calendarID); } </script> and i am setting calendarID in this way: <script type="text/javascript"> calendarID = "<%=calDate.ClientID%>"; </script> there is no cal.selectedDate or anything like this... any help?

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  • Javascript clears a variable after there is no further reference it

    - by Praveen Prasad
    It is said, javascript clears a variable from memory after its being referenced last. just for the sake of this question i created a JS file with only one variable; //file start //variable defined var a=["Hello"] //refenence to that variable alert(a[0]); // //file end no further reference to that variable, so i expect javascript to clear varaible 'a' Now i just ran this page and then opened firebug and ran this code alert(a[0]); Now this alerts the value of variable, If the statement "Javascript clears a variable after there is no further reference it" is true how come alert() shows its value. Is it because all variable defined in global context become properties of window object, and since even after the execution file window objects exist so does it properties.

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  • JavaScript Data Binding Frameworks

    - by dwahlin
    Data binding is where it’s at now days when it comes to building client-centric Web applications. Developers experienced with desktop frameworks like WPF or web frameworks like ASP.NET, Silverlight, or others are used to being able to take model objects containing data and bind them to UI controls quickly and easily. When moving to client-side Web development the data binding story hasn’t been great since neither HTML nor JavaScript natively support data binding. This means that you have to write code to place data in a control and write code to extract it. Although it’s certainly feasible to do it from scratch (many of us have done it this way for years), it’s definitely tedious and not exactly the best solution when it comes to maintenance and re-use. Over the last few years several different script libraries have been released to simply the process of binding data to HTML controls. In fact, the subject of data binding is becoming so popular that it seems like a new script library is being released nearly every week. Many of the libraries provide MVC/MVVM pattern support in client-side JavaScript apps and some even integrate directly with server frameworks like Node.js. Here’s a quick list of a few of the available libraries that support data binding (if you like any others please add a comment and I’ll try to keep the list updated): AngularJS MVC framework for data binding (although closely follows the MVVM pattern). Backbone.js MVC framework with support for models, key/value binding, custom events, and more. Derby Provides a real-time environment that runs in the browser an in Node.js. The library supports data binding and templates. Ember Provides support for templates that automatically update as data changes. JsViews Data binding framework that provides “interactive data-driven views built on top of JsRender templates”. jQXB Expression Binder Lightweight jQuery plugin that supports bi-directional data binding support. KnockoutJS MVVM framework with robust support for data binding. For an excellent look at using KnockoutJS check out John Papa’s course on Pluralsight. Meteor End to end framework that uses Node.js on the server and provides support for data binding on  the client. Simpli5 JavaScript framework that provides support for two-way data binding. WinRT with HTML5/JavaScript If you’re building Windows 8 applications using HTML5 and JavaScript there’s built-in support for data binding in the WinJS library.   I won’t have time to write about each of these frameworks, but in the next post I’m going to talk about my (current) favorite when it comes to client-side JavaScript data binding libraries which is AngularJS. AngularJS provides an extremely clean way – in my opinion - to extend HTML syntax to support data binding while keeping model objects (the objects that hold the data) free from custom framework method calls or other weirdness. While I’m writing up the next post, feel free to visit the AngularJS developer guide if you’d like additional details about the API and want to get started using it.

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  • What should JavaScript be renamed to [closed]

    - by Evan Plaice
    Background: I have been watching Douglas Crockford's series of presentation about JavaScript History (which I highly recommend) lately and a one comment of his specifically piqued my attention. The trademark for 'JavaScript' is owned by Oracle History: Due to time constraints at Netscape, the language was literally written in weeks and released in very buggy form. To make it seem more appealing, Netscape picked JavaScript to appeal to the massively growing population of Java developers. Unfortunately, this pissed off Sun and stirred up a lot of controversy between the two organizations. At some point, they came to an agreement whereby Netscape was given permission to use the name as long as Sun owned the trademark. Some people incorrectly refer to JavaScript as ECMAScript because that's where the standard for the language is registered but, aside from it's current marketing-driven label, it doesn't really have a name. Fast Forward Sun goes down only to be swallowed by Oracle, who has no reservations about litigating for profit, now owns the name. So... If Oracle decides and forces JavaScript to take on a new name, what name would best represent the language?

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  • Performance: recursion vs. iteration in Javascript

    - by mastazi
    I have read recently some articles (e.g. http://dailyjs.com/2012/09/14/functional-programming/) about the functional aspects of Javascript and the relationship between Scheme and Javascript (the latter was influenced by the first, which is a functional language, while the O-O aspects are inherited from Self which is a prototyping-based language). However my question is more specific: I was wondering if there are metrics about the performance of recursion vs. iteration in Javascript. I know that in some languages (where by design iteration performs better) the difference is minimal because the interpreter / compiler converts recursion into iteration, however I guess that probably this is not the case of Javascript since it is, at least partially, a functional language.

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  • How to use html and JavaScript in Content Editor web part in SharePoint2010

    - by ybbest
    Here are the steps you need to take to use html and JavaScript in content editor web part. 1. Edit a site page and add a content editor web part on the page. 2. After the content editor is added to the page, it will display on the page like shown below 3. Next, upload your html and JavaScript content as a text file to a document library inside your SharePoint site. Here is the content in the document <script type="text/javascript"> alert("Hello World"); </script> 4. Edit the content editor web part and reference the file you just uploaded. 5. Save the page and you will see the hello world prompt. References: http://stackoverflow.com/questions/5020573/sharepoint-2010-content-editor-web-part-duplicating-entries http://sharepointadam.com/2010/08/31/insert-javascript-into-a-content-editor-web-part-cewp/

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  • data handling with javascript

    - by Vincent Warmerdam
    Python has a very neat package called pandas which allows for quick data transformation; tables, aggregation, that sort of thing. A lot of these types of functionality can also be found in the python itertools module. The plyR package in R is also very similar. Usually one woud use this functionality to produce a table which is later visualized with a plot. I am personally very fond of d3, and I would like to allow the user to first indicate what type of data aggregation he wants on the dataset before it is visualized. The visualisation in question involves making a heatmap where the user gets to select the size of the bins of the heatmap beforehand (I want d3 to project this through leaflet). I want to visually select the ideal size of the bins for the heatmap. The way I work now is that I take the dataset, aggregate it with python and then manually load it in d3. This is a process that takes a lot of human effort and I was wondering if the data aggregation can be done through the javascript of the browser. I couldn't find a package for javascript specifically built for data, suggesting (to me) that this is a bad idea and that one should not use javascript for the data handling. Is there a good module/package for javascript to handle data aggregation? Is it a good/bad idea to do the data aggregation in javascript (performance wise)?

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  • JavaScript evolution -- weeding out the confusion [closed]

    - by good_computer
    There was JavaScript v1.3 (I guess) that we all started with. Then there was JavaScript 2.0 that Adobe implemented (ActionScript) but was abandoned later. Then came E4X. Then ES5. There is also ES harmony. I am really confused about which version is the latest and where is the standards body going. Can someone describe the whole chronology of JavaScript / ECMAScript evolution and the important differences between those versions?

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  • Interactive map using javascript [on hold]

    - by Denis
    Im trying to learn HTML and javascript. But i cant find any information about how to create interactive map/picture using javascript. Ex. I take a map where is a part of my town and write some information about like few buildings there, so after i put my mouse over those buildings the information will be displayed. It should look similar to this http://davidlynch.org/projects/maphilight/docs/demo_usa.html I need to use the javascript to make it done.

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  • Long Press in JavaScript?

    - by Randy Mayer
    Hi, Is it possible to implement "long press" in JavaScript (or jQuery)? How? HTML <a href="" title="">Long press</a> JavaScript $("a").mouseup(function(){ // Clear timeout return false; }).mousedown(function(){ // Set timeout return false; }); Thank you!

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  • JAVASCRIPT changing on click

    - by Webby
    Hello, Id like some help changing this javascript onclick event to just load the data on page the page load... Preferably not using the body on load tag... So obviously I'd pre set the var for term inside the script term rather than the excisting on click event.. Hope that made sense <p><a id="keywordlink" href="?term=wombats">Get keywords for wombats</a></p> <script type="text/javascript" src="keywords.js"></script> <script type="text/javascript"> var x = document.getElementById('keywordlink'); if(x){ x.onclick = function(){ var term = this.href.split('=')[1]; this.innerHTML += ' (loading...)'; KEYWORDS.get(term,seed); return false; } } function seed(o){ var div = document.createElement('div'); var head = document.createElement('h2'); head.innerHTML = 'Keywords for '+o.term; div.appendChild(head); var p = document.createElement('p'); p.innerHTML = o.toplist; div.appendChild(p); var head = document.createElement('h3'); head.innerHTML = 'Details:'; div.appendChild(head); var list = document.createElement('ol'); for(var i=0,j=o.keywords.length;i<j;i++){ var li = document.createElement('li'); li.innerHTML = o.keywords[i].term + '('+o.keywords[i].amount+')'; list.appendChild(li); } div.appendChild(list); x.parentNode.replaceChild(div,x); } </script>

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  • How often do you find javascript disabled on browsers?

    - by Mark Redman
    I have started using ajax/jQuery in our websites / application. There are many plugins that support degrading the javascript to browsers that dont have javascript enabled and techniques to support this. What are peoples thoughts on javascript support, we build applications rather than just websites and are looking to just support javascript enabled browsers as a pre-requisite assuming that most people or companies have javascript enabled. Do you find most people have javascript? do you monitor the percentage of javascript/non-javascript browsers (I guess this can be done with website stats) and what are the numbers regarding this?

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  • Common programming mistakes for Scala developers to avoid

    - by jelovirt
    In the spirit of Common programming mistakes for Java developers to avoid? Common programming mistakes for JavaScript developers to avoid? Common programming mistakes for .NET developers to avoid? Common programming mistakes for Haskell developers to avoid? Common programming mistakes for Python developers to avoid? Common Programming Mistakes for Ruby Developers to Avoid Common programming mistakes for PHP developers to avoid? what are some common mistakes made by Scala developers, and how can we avoid them? Also, as the biggest group of new Scala developers come from Java, what specific pitfalls they have to be aware of? For example, one often cited problem Java programmers moving to Scala make is use a procedural approach when a functional one would be more suitable in Scala. What other mistakes e.g. in API design newcomers should try to avoid.

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  • Scope of This JavaScript Variable

    - by dkris
    I have a question and an issue wrt the code below: My question is what is the scope of the variable loaded here. The reason why i ask this is the onload="if(loaded==1)inittextarea() code is working fine on Firefox and not IE8. Why is this happening? Is there something specific i need to do here? Or is it not a valid practice? <html> <head> <title>Some Page</title> <link rel="stylesheet" href="../css/default.css" type="text/css"> <script type="text/javascript"> var loaded = 0; /*Point of interest*/ function jsLoaded() { loaded =1; } </script> <script type="text/javascript"> function inittextarea() { alert("test") tinyMCE.init({ elements : "content", theme : "advanced", readonly : true, mode : "exact", theme : "advanced", readonly : true, setup : function(ed) { ed.onInit.add(function() { tinyMCE.activeEditor.execCommand("mceToggleVisualAid"); }); } }); } </script> <script src="../js/tiny_mce/tiny_mce.js" onload="jsLoaded()" type="text/javascript"></script> </head> <body onload="if(loaded==1)inittextarea()"><!--Works on Firefox only--> *Usual stuff* </body></html> Any pointers please?

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  • Javascript doesnt update

    - by Trikam
    Hi all, I have a function that passes a parameter which is a function call and then i use setTimeout to call this passed function call. now i tried two methods with setTimout to raise the event and i used function.call(). When this passed parameter function call was raised none of the javascript was being updated, below is the javascript which im using to raise the event and the javascript which is supposed to be updated: The function being passed is [context] - function() { ErrorMessageFileSelect('diverrortextchoosechannal','The file chosen is to big, you must choose a file less than 1MB'); } function FileSizeOnLoad(contentLength,context) { if (context != null) { // context.call(); setTimeout(context,0); // or context.call(); } else { $('#inputHiddenFileSizeField').val(contentLength); DisplayChoseFileInformation(contentLength); } } //this is where the update should happen function ErrorMessageFileSelect(className, errorMessage) { $('div.' + className).text(errorMessage); alert($('div.' + className).text()); } Is there somthing im missing, can someone help me with this issue please. Thanks

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  • JavaScript: Very strange behavior with assigning methods in a loop

    - by Andrey
    Consider this code below: <a href="javascript:void(-1)" id="a1">a1</a> <a href="javascript:void(-1)" id="a2">a2</a> <script type="text/javascript"> var buttons = [] buttons.push("a1") buttons.push("a2") var actions = [] for (var i in buttons) { actions[buttons[i]] = function() { alert(i) } } var elements = document.getElementsByTagName("a") for (var k = 0; k < elements.length; k++) { elements[k].onclick = actions[elements[k].id] } </script> Basically, it shows two anchors, a1 and a2, and I expect to see "1" and "2" popping up in an alert when clicking on corresponding anchor. It doesn't happen, I get "2" when clicking on either. After spending an hour meditating on the code, I decided that it probably happens because dynamic onclick methods for both anchors keep the last value of "i". So I change that loop to for (var i in buttons) { var local_i = i.toString() actions[buttons[i]] = function() { alert(local_i) } } hoping that each dynamic function will get its own copy of "i" with immediate value. But after this change I get "1" popping up when I click on either link. What am I doing wrong? It's a huge show stopper for me.

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  • passing the parent form on the onclick event to javascript function

    - by user1051505
    Hi I am trying to pass variables on the onclick event to a javascript function. I am trying the following way, I can't get the input value in the javascript function.(I am expecting an alert of 1.) Is it the right way of doing this? Please help. <head> <script> function submit_value(form) { alert(form.ip.value); } </script> </head> <table> <tr> <form> <td> <input id="ip" type="text" value="1"> </td> <td> <a href="javascript:;" onClick="submit_value(this)">Button</a> </td> </form> </tr> </table>

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  • Javascript Noob Question. Need Help With Simple Script

    - by three3
    Hi everyone, I am new to JavaScript (only a couple of days of reading a book) and I am stuck on this code snippet. I have looked at it over and over again but cannot seem to figure out why it is not working. I am sure it is something really simple that I have just looked over but I really just need a fresh pair of eyes to look at this. The code is supposed to update a placeholder image on a page without the page having to reload. But when I am clicking on the link of an image, it is taking me to the link where the image is located instead of replacing the placeholder image. Here is my HTML code: <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> <title>Image Gallery</title> <script type="text/javascript" src="scripts/showPic.js"></script> </head> <body> <h1>Snapshots</h1> <ul> <li> <a href="images/cat.jpg" onclick="showPic(this); return false;" title="A Cat">Cat</a> </li> <li> <a href="images/night.jpg" onclick="showPic(this); return false;" title="Night">Night</a> </li> <li> <a href="images/coke.jpg" onclick="showPic(this); return false;" title="Coke">Coke</a> </li> <li> <a href="images/sport.jpg" onclick="showPic(this); return false;" title="Sports">Sport</a> </li> <li> <a href="images/mnms.png" onclick="showPic(this); return false;" title="MnM's">MnM's</a> </li> <li> <a href="images/kid.jpg" onclick="showPic(this); return false;" title="A Kid">Kid</a> </li> </ul> <br /> <img id="placeholder" src="images/placeholder.jpg" alt="Place Holder Image" /> </body> </html> And here is the JavaScript function I am using to get this done: <script type="text/javascript"> function showPic(whichpic) { var source = whichpic.getAttribute("href"); var placeholder = document.getElementById("placeholder"); placeholder.setAttribute("src",source); } </script> Any help is greatly appreciated and thanks in advance for the help.

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