§The Play cache API

The default implementation of the Cache API uses EHCache. You can also provide your own implementation via a plug-in.

§Importing the Cache API

Add cache into your dependencies list. For example, in build.sbt:

libraryDependencies ++= Seq(
  cache,
  ...
)

§Accessing the Cache API

The cache API is provided by the play.api.cache.Cache object. It requires a registered cache plug-in.

Note: The API is intentionally minimal to allow several implementation to be plugged. If you need a more specific API, use the one provided by your Cache plugin.

Using this simple API you can either store data in cache:

Cache.set("item.key", connectedUser)

And then retrieve it later:

val maybeUser: Option[User] = Cache.getAs[User]("item.key")

There is also a convenient helper to retrieve from cache or set the value in cache if it was missing:

val user: User = Cache.getOrElse[User]("item.key") {
  User.findById(connectedUser)
}

To remove an item from the cache use the remove method:

Cache.remove("item.key")

§Caching HTTP responses

You can easily create smart cached actions using standard Action composition.

Note: Play HTTP Result instances are safe to cache and reuse later.

Play provides a default built-in helper for standard cases:

def index = Cached("homePage") {
  Action {
    Ok("Hello world")
  }
}

Or even:

def userProfile = Authenticated {
  user =>
    Cached(req => "profile." + user) {
      Action {
        Ok(views.html.profile(User.find(user)))
      }
    }
}

Next: Calling web services