In this section, thought to talk about HTTP-Client usage in angular and how its different from existing HTTP Module. It has RxJS Observable-based API. It means that the multiple calls to the HTTP module will return an observable, which we need to subscribe.
If we don’t subscribe to these observables, it won’t work.
If we subscribe multiple times to these observables, multiple HTTP requests will be triggered.
If HTTP request is successful, it will emit only one value and then complete
If HTTP request fails, then these observables will emit an error.
Thought to share my latest project in collaboration with Chander Dhall. Chander and I started discussing on this project couple of months back and thought to collaborate in the project which is going to give more meaningful and professional product as an end result. Before talking anything about this book, I would like to put one disclaimer ahead of time. “This book doesn’t mean for freshers or for those computer professionals” . This I am saying because this book uses tons of client/server and many more sophisticated concepts which may appear overwhelming to freshers or to those just started programming. This book is all about how to marry all these technologies together and come out with a final industry standard product. Hence this book is meant for professionals who are good with basics at least. Having said that, now let me give glimpse of the book with complete first chapter.
Disclaimer:- This post is for those guys, who have been working with PWAs.
In this section, thought to talk about one issue, which I faced while developing my first PWA (Progressive Web App). Although, I have not spoken about how to get started with PWA in any posts so far. But, will talk about the same in coming days.
In the last section, we have understood how to use template driven forms in Angular. In this section, we will focus on how to make use of reactive forms. This approach allows user to create form in greater detail. Here, we will create the forms programmatically in TypeScript.
In the last section, we have seen how to register controls, how we can submit the form and also which properties this form has. In this section, we will extend the Forms learning from the last point. Basically, we will see start with local reference way of accessing the form. Therefore, when I mention, local reference, it means I am referring to @ViewChild() property.
In this section, we are going to talk about dynamically importing modules and its related components. Say for instance, your CORE SPA is hosted on one server. And different teams are basically building different features as modules, which needs to be injected as part dependency injection. Idea is keeping Core part leaner and meaner. Then how could we achieve the same. In the last post, we have seen similar kind of post, where in we injected modules dynamically but, module was known at compile time as we have used webpack’s import which basically takes path to module as input parameter. In this case, module’s can be injected by reading some kind of metadata coming from somewhere. Hence, you can have get some JSON files with some metadata say what modules’ and related dependencies to load. Then, it will load accordingly
In this section, we are going to see, how to dynamically import modules and other related components. In enterprise apps, there might be a scenario, where in you end up loading the modules based on some metadata, say which is coming from some REST call may be. In those scenarios, this kind of implementation is needed. We will discuss Lazy Loading in detail when we talk about those scenarios. However, let’s look at the code where we lazy load modules with all its dependencies.