Angular Service Restangular Caching

问题

Are there scenarios where an angular service will cache Restangular/$http calls without being explicitly told to do so? For example I have a service doing something like this:

    function getSomeThings(){
        return Restangular.one('things').get().then(function (thing) {
            return thing;
        });
    }

This service gets called every time a page refreshes (it's in the UI-router route resolve). Is there any chance that this call WON'T be made every time, but will be cached by Angular somehow, without explicitly being told to do so?

I am familiar with caching explicitly like so:

RestangularProvider.setDefaultHttpFields({cache: true});

This is NOT the intent. My question is whether angular services have some innate caching logic, and if so, how to override it.

回答1:

By default Restangular doesn't implement any caching strategies or scenarios, you will need to build your owns. As far as i know, those are what you can do with cache when working with Restangular :

You can cache everything as you said but you might find yourself working with stale data, so be careful with that :
```
RestangularProvider.setDefaultHttpFields({cache: true});
```

You can cache response for single requests like :

function getSomeThings(){
    Restangular.one('thing', 123).withHttpConfig({ cache: true}).get().then(function (thing) {
        return thing;
    });
}

You can involve a custom $cacheFactory instance to expire or invalidate cached responses when necessary by invoking this : $cacheFactory.get('$http').removeAll()

You can roll in your own cache interface instead of setting true to the cache. This is a factory example that I'm using to remove all cached data whenever I'm sending a create, update or delete request :

    .factory('HTTPCache', ['Restangular', '$cacheFactory', 
      function(Restangular, $cacheFactory) {
       var service = {};
       var cache;

       // Creates the cache
       service.init = function() {
           cache = $cacheFactory('http');
           Restangular.setDefaultHttpFields({cache: cache});

           Restangular.setResponseInterceptor(function(response, operation) {
               if (operation === 'put' || operation === 'post' || operation === 'remove') {
                   cache.removeAll();
               }
               return response;
           })
       }

       return service;

    }])

来源：https://stackoverflow.com/questions/31823091/angular-service-restangular-caching

标签

angularjs

restangular