AngularJS, the Google-maintained open source frontend structural framework for building dynamic web applications has the potential of catapulting your career to newer heights of success. HTML can be used as the template language whose syntaxes can be extended for embedding components in an agile manner on your application.
Any application that you build with AngularJS can be vulnerable to bugs. During AngularJs training, you will come across test-driven development or defensive programming for avoiding bugs. But they still might creep in howsoever diligently you develop the app. A critical skill to incorporate in your repertoire is to debug AngularJS applications speedily for bringing down the time to market for software.
Ways to Debug AngularJS Applications
A rewarding career as an AngularJS application developer depends largely on your knowledge of various troubleshooting methods that streamline bug identification and elimination. Organizations prefer those professionals who can bring down turnaround time and can assure a hassle-free experience for app users.
Since debugging constitutes an essential element of any app development endeavour, it is expected that you will be aware of top ways to address flaws in the app’s code. Discussed below are the major ways accomplished AngularJS programmers handle challenges in codes.
1) Inserting tap () Between Operators
Operator chains employing RxJs operators are hard to debug. But, the presence of .tap() allows for easier inspection of the chain. A chain can be observed without any modification. The pipeable operator tap allows debugging without transforming values.
2) Using the ng.probe Instance
The command ‘ng.probe($0).componentInstance’ can be used on the console for monitoring the state of the component that you have selected from the Elements tab. The global variable $0 takes on the value of the element selected recently by you. For inspecting the 4 earlier DOM elements, you can use $1 to $4 instead. Execution of ng.probe($0) only allows inspection of info like selected component’s parent, listeners list etc. Remember to keep the debug mode enabled.
3) Utilizing in-built Angular Profiler
Angular applications can be profiled using the inherent profiler ‘timeChangeDetection’. By executing ng.profiler.timeChangeDetection(), any change made to the application can be detected. You will also be intimated about the time in which a round of change detection for the present state of the user interface has been completed. The recommended time is lower than 3ms.
4) Using The Chrome Extension
Augury, the Chrome extension, represents Angular components visually on the page along with information like dependencies, router, change detection state, etc. The ‘Component Tree’ tab offered under ‘Properties’ allows inspection of the component’s state. The component’s source code can also be inspected with ‘View Source’ link. You can also view the component’s visual hierarchy and related dependency injections through ‘Injector Graph’. The complete array of defined routes presently loaded in the app can be viewed under ‘Router Tree’. So, the component which is loading lazy will be marked as ‘Lazy’ beside component. You can identify non-lazy loaded routes for improving the application’s performance. Debugging becomes really easy with Augury.
5) Through Network Throttling
If your application is experiencing issues because of a slow network, it can be because that you had tested your app on a fast network which prevented the bug from surfacing. For debugging this scenario, a custom speed can be added for the network by keeping the KB/s low. Reproduce the app on this slow network. This debugging technique is useful if you want to throttle the CPU to observe how the app would behave in older phones with lesser processing power.
6) Using Conditional Breakpoints
For Chrome Dev Tools, breakpoints can be used in place of debugger statement (the statement breaks the application at the point where it is placed). With this, you need not wait for the compilation and refreshing of application before the debugger statement can be applied. Breakpoints can be enabled and disabled singularly. Within the source file, a conditional breakpoint can be added with a right click on the line number. Upon the fulfillment of specific criteria, the breakpoint would be triggered. Console.log() statement can also be used for adding a breakpoint. Undefined is returned by the statement, hence the debugger would not be stopped at error point. Instead, you would get console output to facilitate debugging.
Is Angular Training Worth Doing?
The demand for Angular JS developers is gradually increasing. The corresponding salaries being offered at different levels are also getting more attractive. It is worth investing in an AngularJs course for giving your career a much-needed head start. Enrol now in an accredited training module from any renowned institute and become eligible to earn handsome salaries drawn by the industry’s Angular professionals as depicted below.