I want to serve a static file from a Scala Play controller. I am looking for something that would allow me to do something like this example below.
NOTE: This obviously does not work.
It is very possible that I am look at the problem in the wrong way, I however do NOT want to redirect to the app.html
def loadApplication(): EssentialAction = Action.sync { request =>
val contents = Assets.contentsOf("/public/assets/app.html") //This doesnot return the contents, but that is what I want
Ok(contents)
}
You can just use the Assets and return contents via that. You might have to tweak the path though:
class MyController #Inject() (assets: Assets) extends Controller {
def loadApplication(): Action[AnyContent] = Action.async { request =>
assets.at("/public/assets/", "app.html").apply(request)
}
}
More information may be found in the documentation: https://www.playframework.com/documentation/2.5.x/AssetsOverview#The-Assets-controller
Also note that you can map a route to your assets instead of statically referencing the file from the controller, like so:
GET /assets/*file controllers.Assets.at(path="/public", file)
Related
I have many controllers in my play 2.4.x application.
I want to get a list of all route URLs pointing their respective controllers. I know how to get the URL from the current request. But I need a list of all the URLs available inside a play application.I want to generate this list dynamically because URLs can be changed/added/deleted in future.
So,is there some way I can generate this URL list dynamically ? Or do I have the obligation to store all the URLs statically somewhere in cache or dictionary ?
I obtained the desired list by using the documentation method provided by Router trait. The documentation method returns Seq[(String, String, String)] .Here each tuple has the format:
( {http-method} , {url} , {controller method} )
The Router trait is extended by all the autogenerated Routes.scala classes. Scala-compiler generated a separate Routes.scala for each routes file in the application. These auto-generated Routes.scala files implement all the methods of Router trait including the documentation method that we discussed above.
So,to get list of all URLs, I simply had to inject the Router trait and then access the documentation method:
import play.api.routing.Router
class MyClass #Inject()(router: Router) {
def getAllURLs:Seq[String] = router.documentation.map(k => k._2)
}
Update for Play 2.7, Scala:
class MyController #Inject()(routesProvider: Provider[play.api.routing.Router]) {
lazy val routes: Seq[(String, String, String)] = routesProvider.get.documentation
}
from discussion for play 2.6
In response to the accepted answer: Note that if you're working in a Controller and you try to inject the Router, you'll get a Circular Dependency error (because the Router depends on your Controller). You can fix this by doing the following:
private final Provider<Router> routerProvider;
#Inject
public MainController(Provider<Router> routerProvider) {
this.routerProvider = routerProvider;
}
And then
// later in execution
Router router = routerProvider.get();
if (!router.documentation().isEmpty()) {
html.append("<ul>");
router.documentation().forEach(doc ->
html.append("<li>")
.append("<b>Method</b>: ")
.append(doc.getHttpMethod())
.append(" <b>Path</b>: ")
.append(doc.getPathPattern())
.append(" <b>Controller</b>: ")
.append(doc.getControllerMethodInvocation())
.append("</li>"));
html.append("</ul>");
}
After upgrading my project to Play Framework 2.5.4 from 2.4.8, I'm having issue while working with session. There are to methods in my controller to test the issue:
def test = Action { implicit request =>
Redirect(controllers.routes.Carts.test2()).withSession(new Session(Map("user" -> "customer")))
}
def test2 = Action { implicit request =>
Ok(request.session.data.toString())
}
Basically test method adds session and redirects to test2 method. When I open page with test method url after redirect I'm getting what I need in the browser:
Map(user -> customer)
But if I refresh page after that I'm getting:
Map(csrfToken ->
ce1a6222484f378d38ab3534c2b400191270395d-1470238791014-c988ce3fe47259173166949a)
So, seems like session works for one request only and then overwrites with csrfToken. I have disabled all the filters. My class with filters looks like this:
class Filters #Inject() () extends HttpFilters {
val filters = Seq.empty
}
Can't understand what is wrong with my code. The same code was working fine before upgrade.
Check in ur application.conf if session.secure is true bring it to
play.http.session.secure=false
A question about asset fingerprinting in Play.
How to ask Play to embed ETags in URLs without using a third-party plugin?
E.g., if /css/resource.css had the ETag of 1234, then it would become /css/responsive-1234.css.
Related questions: Custom ETag algorithm for asset fingerprinting & Automatically Insert ETag (asset fingerprinting) as comment at top of the resource
There'll be the "out" routing and the "in" reverse routing. Firstly the "out" routing:
package controllers
import play.api.mvc._
object Resources extends Controller {
def fingerprintedUrl(path: String): String = {
// calculates ETag and add to URL path
val pathWithEtag = addEtagToPath(path)
pathWithEtag
}
}
Then in templates use the following for example:
<script src="#Resources.fingerprintedUrl("js/toolkit.js")"></script>
Now the reverse routing, add the following to the same controller:
def at(path: String): Action = {
val pathWithoutEtag = removeEtagFromPath(path)
Assets.at("/public", pathWithoutEtag)
}
Then in routes:
GET /resources/*file controllers.Resources.at(file)
I've declared an object which gets instantiated on application start. I want to access it inside a controller, which is part of a plugin. I want to be able to use that plugin, but I can't seem to get past the first part -- finding the MyWebsocketConnection object. None of the examples show how to do this. I don't want to inject into the controller because I'm writing a plugin (I saw static examples of how to do that somewhere).
Global.scala, plugin application \app\Global.scala
object Global extends GlobalSettings {
object MyWebsocketConnection {
val logger = // return something that gets instantiated once, like websocket object for logging to ui
}
class MyWebsocketConnection {
import MyWebsocketConnection.logger
}
override def onStart(app: Application) {
Logger.info("Application has started...");
}
}
My custom logging plugin controller:
MyLogger.Scala, plugin application \app\controllers\MyLogger.scala
object MyLogger {
def info(message: String) = {
// THIS CAN'T BE FOUND ?
// MyWebsocketConnection.logger.send(message)
}
}
So, from the Play! 2.0 app that references the plugin, I would (probably) do something like below, but I can't even get past the part before this:
MyFutureController.scala, another Play! application \app\controllers\MyFutureController.scala
object MyFutureController extends Controller {
def someRandomMethod = Action {
// Custom logging
MyLogger.info("Here's my log message!");
Ok("This documentation stinks!")
}
}
There is also workaround #3: move your Global class to a package and specify its fully qualified name in application.conf file, like so:
global= my.packaged.Global
The problem is that your Global objects resides in default package. And in Java, classes from default package can't be referenced from other packages, they are accessible only within the same package (default).
I see two workarounds of this problem.
Move MyWebsocketConnection to some named package (say config) so it can be accessible in your application.
object MyLogger {
def info(message: String) = {
config.MyWebsocketConnection.logger.send(message)
}
}
Move your whole application into single package (but it is a lot of pain)
foo
|--controllers
|--models
|--views
|--Global.scala
Then Global object will resides in foo package and will be accessible within application.
What’s the preferred way to handle 404 errors with Play 2.0 and show a nice templated view?
You can override the onHandlerNotFound method on your Global object, e.g.:
object Global extends GlobalSettings {
override def onHandlerNotFound(request: RequestHeader): Result = {
NotFound(views.html.notFound(request))
}
}
Please note that there are really two different problems to solve:
Showing a custom 404 page when there is "no handler found", e.g. when the user goes to an invalid URL, and
Showing a custom 404 (NotFound) page as a valid outcome of an existing handler.
I think the OP was referring to #2 but answers referred to #1.
"No Handler Found" Scenario
In the first scenario, for "no handler found" (i.e. invalid URL), the other answers have it right but to be more detailed, per the Play 2.1 documentation as:
Step 1: add a custom Global object:
import play.api._
import play.api.mvc._
import play.api.mvc.Results._
object Global extends GlobalSettings {
override def onHandlerNotFound(request: RequestHeader): Result = {
NotFound(
views.html.notFoundPage(request.path)
)
}
}
Step 2: add the template. Here's mine:
#(path: String)
<html>
<body>
<h1>Uh-oh. That wasn't found.</h1>
<p>#path</p>
</body>
</html>
Step 3: tweak your conf/application.conf to refer to your new "Global". I put it in the controllers package but it doesn't have to be:
...
application.global=controllers.Global
Step 4: restart and go to an invalid URL.
"Real Handler can't find object" Scenario
In the second scenario an existing handler wants to show a custom 404. For example, the user asked for object "1234" but no such object exists. The good news is that doing this is deceptively easy:
Instead of Ok(), surround your response with NotFound()
For example:
object FruitController extends Controller {
def showFruit(uuidString: String) = Action {
Fruits.find(uuidString) match {
case Some(fruit) => Ok(views.html.showFruit(fruit))
// NOTE THE USE OF "NotFound" BELOW!
case None => NotFound(views.html.noSuchFruit(s"No such fruit: $uuidString"))
}
}
}
What I like about this is the clean separation of the status code (200 vs 404) from the HTML returned (showFruit vs noSuchFruit).
HTH
Andrew
If you want to do the same using Java instead of Scala you can do it in this way (this works for play framework 2.0.3):
Global.java:
import play.GlobalSettings;
import play.mvc.Result;
import play.mvc.Results;
import play.mvc.Http.RequestHeader;
public class Global extends GlobalSettings {
#Override
public Result onHandlerNotFound(RequestHeader request) {
return Results.notFound(views.html.error404.render());
}
}
Asumming that your 404 error template is views.html.error404 (i.e. views/error404.scala.html).
Please note that Play development team are making lots of efforts to move away from global state in Play, and hence GlobalSettings and the application Global object have been deprecated since version 2.4.
HttpErrorHandler.onClientError should be used instead of
GlobalSettings.onHandlerNotFound. Basically create a class that inherits from HttpErrorHandler, and provide an implementation for onClientError method.
In order to find out type of error (404 in your case) you need to read status code, which is passed as a one of the method arguments e.g.
if(statusCode == play.mvc.Http.Status.NOT_FOUND) {
// your code to handle 'page not found' situation
// e.g. return custom implementation of 404 page
}
In order to let Play know what handler to use, you can place your error handler in the root package or configure it in application.conf using play.http.errorHandler configuration key e.g.
play.http.errorHandler = "my.library.MyErrorHandler"
You can find more details on handling errors here: for Scala or Java.
This works in 2.2.1. In Global.java:
public Promise<SimpleResult> onHandlerNotFound(RequestHeader request) {
return Promise.<SimpleResult>pure(notFound(
views.html.throw404.render()
));
}
Ensure that you have a view called /views/throw404.scala.html
This works in 2.2.3 Play - Java
public Promise<SimpleResult> onHandlerNotFound(RequestHeader request) {
return Promise<SimpleResult>pure(Results.notFound(views.html.notFound404.render()));
}
html should be within /views/notFound404.scala.html
Dont forget to add Results.notFounf() and import play.mvc.Results;
For Java, if you want to just redirect to main page, I solved it by this.
#Override
public Promise<Result> onHandlerNotFound(RequestHeader request) {
return Promise.pure(redirect("/"));
}