spring-angular-cache-preloader

Component to pre-fill caches for angular js rest request though index page

Overview

This component can be hooked into a Spring WebMVC application to tunnel REST requests that a single page app makes on first page load through the index page and prefill angular's $http cache with the values.

How to use

Gradle dependency

compile('eu.hinsch:spring-angular-cache-preloader:0.2.0')

Maven dependency

<dependency>
  <groupId>eu.hinsch</groupId>
  <artifactId>spring-angular-cache-preloader</artifactId>
  <version>0.2.0</version>
</dependency>

Configure resource transformer

public class WebMvcConfiguration extends WebMvcConfigurerAdapter {
    @Autowired
    private AngularRestCachePreloadTransformer angularRestCachePreloadTransformer;

    @Override
    public void addResourceHandlers(ResourceHandlerRegistry registry) {
        registry.addResourceHandler("/index.html", "/") // or whatever your welcome page is
                .addResourceLocations("classpath:/location-of-index/")
                .resourceChain(false)
                .addTransformer(angularRestCachePreloadTransformer);
    }
}

Placeholder for generated script

Add {cachePreloadScript} in your index.html (right before the end tag), this will be replaced by <script>...</script>

Turn on caching for request in angular

For example, if you are using ng-resource then you can turn on caching for a request by

$resource('some-url', {}, {
    query : {
        method : 'GET',
        cache : true,
        isArray: true
    }})
    .query();

Configure urls to cache

In application.yml

cache-preload:
  # name of some existing angular module in your app that is being loaded
  angular-module: myapp
  
  cached-urls:
    # static url to be cached (must be the same as configured in $resource)
    - url: some-url
    
    # dynamic url, where the parameter (likely) to be used is known/can be guessed by server
    - url: some-dynamic-url/{some-param}
      parameters:
        # any SpEL expression (with access to any bean)
        some-param: my-expression

Example

See test/java/eu/hinsch/spring/angular/cache/test/TestApplication.java, test/resources/application.yml and test/resources/web/index.html for details.