Being passionate about AngularJS, me and two fellow JDriven colleagues visited the ngEurope conference. The amount of presentations during ngEurope was somewhat overwhelming, especially during the mornings without any scheduled break. Good thing I made some notes, that the slides are already available on-line and that someone published quite detailed notes for all sessions. Without all this I might simply have forgotten about some very interesting and relevant details. During ngEurope there was a all lot of attention for the just released 1.3 version of AngularJS and the coming 2.0 release.
The latest AngularJS 1.3 release features some great performance improvements (3.5x faster digest and 4.4x faster DOM manipulation) and much less pressure on the garbage collector (GC). However in order to achieve this the AngularJS team did decide drop the support for Internet Explorer 8 (which is default IE version on Windows 7). To allow for even more (optional) speed improvement one time (one way) binding support has been added. Using one time binding no $watch will be registered for the binding; typically you would use one time bindings to speed up rendering the elements of ngRepeat. Additionally a lot of improvements are done on the ngModel directive. First of all a $validators pipeline had been introduced as an alternative to invoking $setValidity from a parser / formatter function. Which also fixes the "input not showing invalid model values” bug ( #1422). Yet another great improvement are the new async validators that allows for (asynchronous) model validation on the back-end. The ngModel directive is now accompanied by the ngModelOptions directive that allows you to configure (the controller of) the ngModel directive. We now can specify when we want the model value to be updated. For instance after a short delay (a so called debounce) or on blur (i.e. when focussing another field). And using ngModelOptions we can now configure the usage of (jQuery) style getter / setter function on our model (instead of using plain data properties). Using ngMessages (multiple different) error messages can now be shown much easier in a switch–case like style for a form element. Besides preformance- and ngModel (related) improvements AngularJS also features some other noteworthy features:
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Since version 2.3, Grails supports asynchronous parallel programming to support modern multiple core hardware. Therefore a new Grails command is added to generate asynchronous controllers for domain classes. The generated controller contains CRUD actions for a given domain class. In the example below, we will generate a default asynchronous implementation of a Grails controller. First we create a domain object:
$ grails create-domain-class grails.data.Movie
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Gradle uses the name build.gradle
as the default name for a build file. If we write our build code in a file build.gradle
then we don't have to specify the build filename when we run tasks. We can create build files with a different name other than build.gradle
. For example we can define our build logic in a file sample.gradle
. To run the tasks from this build file we can use the command line option -b
or --build-file
followed by the file name. But we can also change the project settings and set a new default build file name for our project. With the changed project settings we do not have to use the command line options -b
or --build-file
.
Suppose we have the following build file with the name sample.gradle
:
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Since version 2.3 Grails has excellent support for creating REST APIs. This new support comes with some new console commands. Besides the well known generate-controller
command, Grails now comes with a new command which let you generate restful controllers for a given domain class. In the following example, we will create a restful controller using the new generate-restful-controller command.
First we create a domain object
$ grails create-domain-class grails.data.Movie
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When we write Groovy code there is a big chance we also write some closures. If we are working with collections for example and use the each
, collect
or find
methods we use closures as arguments for these methods. We can assign closures to variables and use the variable name to reference to closure. But we can also create a subclass of the Closure
class to implement a closure. Then we use an instance of the new closure class wherever a closure can be used.
To write a closure as a class we must subclass Closure
and implement a method with the name doCall
. The method can accept arbitrary arguments and the return type can be defined by us. So we are not overriding a method doCall
from the superclass Closure
. But Groovy will look for a method with the name doCall
to execute the closure logic and internally use methods from the Closure
superclass.
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If we write a specification for a specific class we can indicate that class with the @Subject
annotation. This annotation is only for informational purposes, but can help in making sure we understand which class we are writing the specifications for. The annotation can either be used at class level or field level. If we use the annotation at class level we must specify the class or classes under test as argument for the annotation. If we apply the annotation to a field, the type of the field is used as the class under test. The field can be part of the class definition, but we can also apply the @Subject
annotation to fields inside a feature method.
In the following example Spock specification we write a specification for the class Greet
. The definition of the Greet
class is also in the code listing. We use the @Subject
annotation on the field greet
to indicate this instance of the Greet
class is the class we are testing here. The code also works with the @Subject
annotation, but it adds more clarity to the specification.
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This second part of the Stateless Spring Security series is about exploring means of authentication in a stateless way. If you missed the first part about CSRF you can find it here. So when talking about Authentication, its all about having the client identify itself to the server in a verifiable manner. Typically this start with the server providing the client with a challenge, like a request to fill in a username / password. Today I want to focus on what happens after passing such initial (manual) challenge and how to deal with automatic re-authentication of futher HTTP requests.
The most common approach we probably all know is to use a server generated secret token (Session key) in the form of a JSESSIONID cookie. Initial setup for this is near nothing these days perhaps making you forget you have a choice to make here in the first place. Even without further using this "Session key" to store any other state "in the session", the key itself is in fact state as well. I.e. without a shared and persistent storage of these keys, no successful authentication will survive a server reboot or requests being load balanced to another server.
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Today with a RESTful architecture becoming more and more standard it might be worthwhile to spend some time rethinking your current security approaches. Within this small series of blog posts we'll explore a few relatively new ways of solving web related security issues in a Stateless way. This first entry is about protecting your website against Cross-Site Request Forgery (CSRF).
CSRF attacks are based on lingering authentication cookies. After being logged in or otherwise identified as a unique visitor on a site, that site is likely to leave a cookie within the browser. Without explicitly logging out or otherwise removing this cookie, it is likely to remain valid for some time. Another site can abuse this by having the browser make (Cross-Site) requests to the site under attack. For example including some Javascript to make a POST to "http://siteunderattack.com/changepassword?pw=hacked" will have the browser make that request, attaching any (authentication) cookies still active for that domain to the request! Even though the Single-Origin Policy (SOP) does not allow the malicious site read access to any part of the response. As probably clear from the example above, the harm is already be done if the requested URL triggers any side-effects (state changes) in the background.
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