I am Using the play Framework 2.7.x
I have a Formular on my controller.list() with a view, let's call it "index". After you click "send" it open's controller.add() where it dos some stuff and then redirects back to controller.list(). If there was an error in the formular (a requiered field was empty) I need the queryString, which was send to controller.add() also redirected to controller.list()
The problem ist that if I do stuff like just passing the request, i get an error that it's not possible to add arguments.
public Result list(Http.Request request)
{
// .... stuff with foo, while foo is an Form<foo> Object
// ... foo.bindFromRequest(request)
ok(views.html.index.render(foo))
}
public Result add(Http.Request request)
{
// not allowed to add request as an argument. only empty is allowed.
return Results.redirect(controllers.routes.Controller.list(request));
}
I would like to just redirect the Form object, so I can handle the error in the controller.list() and not have to generate an extra view for the controller.add(). If I do everything inside controller.list() there is no problem with this code, but I like to use the controller.add() method instead.
Is the an option? except passing every querystring key and value by hand.
After I searched yesterday the half the day, I found something interessting today.
you are not allowed to use a default parameter with =. You have to use an optional default parameter with ?= inside the routes!!!!!
you can implement QueryStringBindable so it's a bit easier to bind the query String. But you still have to bind them "by hand".
Related
In the Struts documentation, it says:
Another common workflow stategy is to first render a page using an alternate method, like input and then have it submit back to the default execute method.
https://struts.apache.org/core-developers/action-configuration.html#post-back-default
How to do it using annotation only? It seems that only the execute() method is called.
In the documentation it's said to render a page can be used an alternate method like input. This means that when you submit a form on the page it can return back with the input result. Usually it happens automatically during validation process if the validation fails or it hasErrors. Then you can submit the form back to the default action's execute method. You don't need to specify a method in the action configuration. Also if you didn't specify the action attribute in the form tag then the same action will execute which was used to render a page.
Configuring actions you can use the same page for success result when rendering a page using GET method and input when POST method is requested.
To use annotations to configure actions mapping you can use a Convention Plugin.
Also note, to map a class method to the action you should put #Action annotation directly on this method rather than on the class.
More detailed explanation and documentation you can find here.
#Namespace("/")
public class ProductAction extends ActionSupport {
public String execute() {
return SUCCESS;
}
#Action(value="product",
results=#Result(location="/product-list.jsp")
)
public String search() {
return SUCCESS;
}
}
Notice, that the method execute is not mapped, so it will not execute. If you need that method execute you should create mapping to it. For this purpose you could place annotation on class or on method execute.
I am a novice with vertx so maybe I am doing something wrong. I am trying to implement the following routes:
router.get("/api/users/").handler(this::getUsers);
router.route("/api/users/:username*").handler(this::checkUsername);
router.get("/api/users/:username/").handler(this::getUser);
router.put("/api/users/:username/").handler(this::addUser);
router.get("/api/users/:username/assignments/").handler(this::getAssignments);
router.post("/api/users/:username/assignments/").handler(this::addAssignment);
router.route("/api/users/:username/assignments/:assignmentId/").handler(this::checkAssignmentId);
router.get("/api/users/:username/assignments/:assignmentId/").handler(this::getAssignment);
Is this the correct way to avoid duplicating this logic in all handlers?
I am trying to chain handlers, where the checkUsername handler reads the username parameter from the path, tries to find a corresponding user, and puts that user in the context. If no user is found, a statuscode 400 is returned. Otherwise the next handler is called. I would like to apply the same principle to the assignmentId parameter.
While trying to implement this, I believe I found a problem with the path, more specifically the trailing slash and star. The documentation states that trailing slashes are ignored. This is not the behavior when there is a parameter in the path. In that case the trailing slash matters. If the path definition contains one and the request does not, vertx returns a 404. It does not make a difference whether or not the parameter is at the end of the path or in the middle.
The same goes for paths ending with a star. This functionality does not work when the path contains a parameter.
You can use a regular expression to avoid duplication of the checkUsername validation check. What I would do is I would have a method like this to check if the username is valid:
private void checkUsername(RoutingContext routingContext){
//The "param0" is the capture group of the regular expression. See the routing config below.
if (isValidUsername(routingContext.request().getParam("param0"))){
routingContext.next();
} else {
routingContext
.response()
.setStatusCode(400)
.end();
}
}
To check the assignment ID I would do something similar:
private void checkAssignmentId(RoutingContext routingContext){
if (isValidAssignmentId(routingContext.request().getParam("assignmentId"))){
routingContext.next();
} else {
routingContext
.response()
.setStatusCode(400)
.end();
}
}
Try to avoid trailing slashes in your paths. I would change the routing handler assignments to be something like this:
router.get("/api/users").handler(this::getUsers);
//By the way, you really want to be using a POST request when adding users just to stick to the principles of REST.
//When you are sending a POST request there is no need to put the username in the URI. You can have it in the request body.
//Please ensure you validate this username using the same validation helper used in your other validations.
router.post("/api/users").handler(this::addUser);
//Use regular expression to match all "/api/users/:username*" URIs
router.routeWithRegex("\\/api\\/users\\/([^\\/]+)").handler(this::checkUsername);
router.get("/api/users/:username").handler(this::getUser);
router.get("/api/users/:username/assignments").handler(this::getAssignments);
router.post("/api/users/:username/assignments").handler(this::addAssignment);
router.route("/api/users/:username/assignments/:assignmentId").handler(this::checkAssignmentId);
router.get("/api/users/:username/assignments/:assignmentId").handler(this::getAssignment);
I am using Restangular to download an object, update it and then attempt to save back to the server using the save method. Here is the code that retrieves the object:
Restangular.one("survey", surveyID).getList().then (
function (response) {
$scope.survey = response[0];
}
);
This sets $scope.survey to a properly "restangularized" object, with the fields that come back from the GET request, along with the methods like save, put, etc.
If I then invoke the following function after making some edits to the $scope.survey object:
$scope.saveChanges = function () {
$scope.survey.save();
};
restangular tries to use the URL /survey/1/undefined for the PUT request (1 is the correct ID for the object).
My survey object doesn't have an id field (it's surveyID instead), and so I suspected this might be the problem. However, replacing the surveyID field with an id field changed the URL to be /survey/1/undefined/1
I have stripped down the object returned by the GET request to be just primitives, and this does not change the situation.
Why is the incorrect route being generated?
II discovered the problem was actually with the REST service; when called with GET /surveys/1, it was returning an array with a single object in it, rather than returning the object itself.
I think this caused restangular to think that a collection was being accessed (note that I was having to call getList rather than get in order to get a properly restangularized object).
I need to be able to handle special characters in a REST call. Specifically the . and / characters.
For example I have a GET route /api/division/{someDivision}. Now, calling this route with a parameter of /api/division/West Canada/ I get a return and everything works as expected. However, I need to be able to support other business divisions which have names such as "Southwest U.S." and "North/South America". Passing these parameters through my route returns a 404 via the api, since I presume, that the http handler thinks that the . and / characters make it think I'm referring to another domain or directory. Is there anyway to work around this so I can pass the needed parameter?
The route:
[HttpGet]
[Route("{division}/information")]
public IHttpActionResult DivisionInfo(string division)
{
...omitted for brevity
You could try setting your route up like this:
[HttpGet]
[Route("/api/information")]
public IHttpActionResult DivisionInfo(string division)
Then you can call GET http://website.com/api/information?division=text.with/special./characters.
try adding [FromUri] before the param:
Route("api/Person/{ID}/[FromUri]{UserName}")]
Lets say I have a form with method=POST on my page.
Now this form has some basic form elements like textbox, checkbox, etc
It has action URL as http://example.com/someAction.do?param=value
I do understand that this is actually a contradictory thing to do, but my question is will it work in practice.
So my questions are;
Since the form method is POST and I have a querystring as well in my URL (?param=value)
Will it work correctly? i.e. will I be able to retrieve param=value on my receiving page (someAction.do)
Lets say I use Java/JSP to access the values on server side. So what is the way to get the values on server side ? Is the syntax same to access value of param=value as well as for the form elements like textbox/radio button/checkbox, etc ?
1) YES, you will have access to POST and GET variables since your request will contain both. So you can use $_GET["param_name"] and $_POST["param_name"] accordingly.
2) Using JSP you can use the following code for both:
<%= request.getParameter("param_name") %>
If you're using EL (JSP Expression Language), you can also get them in the following way:
${param.param_name}
EDIT: if the param_name is present in both the request QueryString and POST data, both of them will be returned as an array of values, the first one being the QueryString.
In such scenarios, getParameter("param_name) would return the first one of them (as explained here), however both of them can be read using the getParameterValues("param_name") method in the following way:
String[] values = request.getParameterValues("param_name");
For further info, read here.
Yes. You can retrieve these parameters in your action class.
Just you have to make property of same name (param in your case) with there getters and setters.
Sample Code
private String param;
{... getters and setters ...}
when you will do this, the parameters value (passed via URL) will get saved into the getters of that particular property. and through this, you can do whatever you want with that value.
The POST method just hide the submitted form data from the user. He/she can't see what data has been sent to the server, unless a special tool is used.
The GET method allows anybody to see what data it has. You can easily see the data from the URL (ex. By seeing the key-value pairs in the query string).
In other words it is up to you to show the (maybe unimportant) data to the user by using query string in the form action. For example in a data table filter. To keep the current pagination state, you can use domain.com/path.do?page=3 as an action. And you can hide the other data within the form components, like input, textarea, etc.
Both methods can be catched in the server with the same way. For example in Java, by using request.getParameter("page").