AngularJS Essentials

Chapter 4
After the header configuration, the request starts to send the custom header:
GET /cars HTTP/1.1
Host: localhost:3412
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:29.0)
Accept: application/json
Accept-Language: pt-br,pt;q=0.8,en-us;q=0.5,en;q=0.3
Accept-Encoding: gzip, deflate
The headers can also be configured through the configuration object of each request.
It will overwrite the default headers configured here.
Caching
To improve the performance of our application, we can turn on the framework's
caching mechanism. It will store each response from the server, returning the same
result every time the same request is made.
However, take care. Some applications demand updated data, and the caching
mechanism may introduce some undesired behavior. In the following code, we
are enabling the cache mechanism:
run.js
parking.run(function ($http) {
$http.defaults.cache = true;
});
Interceptors
The framework also provides an incredible HTTP intercepting mechanism. It allows us
to create common behaviors for different kinds of situations such as verifying whether
a user is already authenticated or to gather information for auditing purposes.
The first is the request interceptor. This interceptor is called before the request is
being sent to the backend. It is very useful when we need to add information such
as additional parameters or even headers to the request.
In the following code, we create an interceptor called httpTimestampInterceptor,
which adds the current time in milliseconds to each request that is made by
the application:
parking.factory('httpTimestampInterceptor', function(){
return{
'request' : function(config) {
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