I have a situation like when i submit the employee form i need to check for a boolean value in employee_controller if it is set then i need to invoke a create action in AddressController. what is the best way to do it ? Whether i need to create an instance like AddressController .new and call the method ? and there is no relationship between employee and address.
Why do you need to call an action in AddressController when you submit and Employee form?
A better/cleaner idea might be to interact with the Address model from within the Employees_controller. Nothing wrong with that!
Related
I have a class "Student" and other class "scoresheet".
Each Professor should be able to fill up a scoresheet for each student. I have been able to create, list, edit the scoresheet with using the default scaffolding options.
However, when a professor is directed to homepage/students he is presented with the default option such as create, edit, delete, and i would also like to add a "score" option, that would go to the create option of the scoresheet model/controller.
I was able to do this, but i would like to know how i can pass the StudentID/name to the scoresheet controller in order to know for which student the scoresheet is being created.
Please advise.
Thank you in advance.
You can use AJAX to send the id as a parameter and call the Controller Action
I created a static scaffolding for my domain class and got a controller for that domain class. The create action of the controller looks like:
def create() {
[userInstance: new User(params)]
}
I wonder why the line:
[userInstance: new User(params)]
has been added. Obviously when the create action is invoked, there wont be any params - so why would this line have been added?
Obviously when the create action is invoked, there wont be any params
Not necessarily - imagine a situation where you want to pre-populate a couple fields in the form of the create view. You could use:
/app/user/create?username=myusername
Which would result in the view's userInstance having a populated username field for display in the form.
This is fundamentally by Spring, the action is called 'binding' and is the action of tie form elements from one jsp(gsp in this case) to the properties of an object and viceversa.
To tie an object to a form, well, you should create it first, how can ypu tie a null object? it's not possible, that is why the new ClassObject(...)
After that in Groovy we have POGO's, and one feature of POGO's is the ability of initialize them with a map, for example:
new User(name:'John',lastname:'Zuñiga')
But in this case there's a lil' of groovy magic with that 'params' object. That comes from Groovy Servlets or Groovlets. How can you obtain a param with Java incoming from a form? Well, with request.getParam("param_name"), but in this case with Groovy you receive a params object, this params object is a map, a Groovy map...Uhm, one second...
If POGO's in Groovy is able to receive a Map as constructor, and the params object is a Map...maybe...oh coolness I can put that map in the constructor of my object, and after Spring do the binding to the form with this new Object, so this object is travelling in actions from this controller so it comes with the properties populated.
I hope this explanation be clear, if you have questions, I'm here...
Regards
There could be params, although in general there wouldn't be.
It allows pre-loading of values, which may be helpful sometimes, including re-displaying the create form.
I have created a instance variable in rails project, which gets its value from a url parameter like example.com/value. This variable is created in new action, now can it also be used in create action, of the same model.
The value is a id of another model altogether and both the models are associated, I need to create the instance variable in former model.
I need to know, for how long the instance variable is available, and can be use the instance variable of one model in another model.
Clarification with real example
Supposingly there are two models, one is User model and other is Referral model. The root is root :to => 'users#new. Now the user will coming here via example.com/value, where value is the id for Referral model. Now using this value I have to increment two fields: One is visits, which shows how many visits did that particular url bring. Other is signup, which will increment if there is a signup using that value.
I have passed this value via routes in users#new, which I use to increment the visits column of Referral model. Now if the users signup, the users#create would be executed, and I want to be able to use the value in the create action as well, to increment the signup column in Referral model.
As of now, I understand that the instance variable I created in new action to store the value cannot be used in create action. Now how can I achieve this.
In general instance variables only last as long as the user's HTTP request, so they can not be created in one action and used in another.
You could try storing the variable in the session, a hidden input field on the HTML form generated by the new action, or in the urls of links generated by the new action.
I don't know exactly what you are doing, but from the names of your two actions it sounds like there is probably an HTML form involved, so I think the best thing is to use a hidden input, something like this:
<input type="hidden" name="model_id" value="<%= #model_id %>" />
Instance variables only last for that call and in the class they are defined, with the exception of the views. If you have a controller with two methods where one method is your route and another is used internally, then it will be available to both, it is also available to your views.
e.g.
test_controller.rb
def index
something_else
p #variable #outputs "foo" in the terminal
end
def something_else
#variable = "foo"
end
However it would not be available between create and new as these would be called in different requests.
In certain Controller I have CRUD methods. In order to access these methods user needs to be logged in. This is why I used [Authorize] attribute for this controller. Now I need additional attribute which would check if item that user wants to view/delete/update belongs to him.
Is it possible and recommended to do this with attribute or you would suggest using check methods inside each method? If you suggest using attribute, could you please provide me some links/instructions?
EDIT:
Ofcourse, if attribute returns false than I don't want to redirect user to login page but show him an error message...
It can be done with a custom Authorize attribute, but it's much cleaner to put the logic inside your controller methods.
The attribute is related to the action being called (the controller class method). On that basis any attribute relating to the user's ownership of the object being manipulated (from your Model) should really be on the entity/class that the user is attempting to manipulate. You'll probably find it easier to validate the user within the Model method rather than using an attribute to achieve this.
In my opinion it is possible, just google for 'Custom Authorize Attribute'.
But maybe it is better to query your database with something like this:
ContextOrSession.Query<Something>.Where(Something.Groups.Intersect(User.Groups).Count>0)
I want to create a form for creating an order. So I have an 'Order' controller. One of the first steps will be to select an existing person to send this order to.
I'm thinking the Create() action method on OrderController will put a new Order object in session. Then I'll need a link that will redirect to another controller, then return a customerID int to this Create() method.
I will have either a SearchController with a FindCustomer() action method, or a Search() action method on the CustomerController.
I have tried the first way. But what I am doing looks pretty messy. Especially considering that I'll need to do this at least one more time on this form, redirecting to the ItemsController to return items to add to the order.
What's the best way to design communication like this between controllers?
I'm not sure why you think you need other controllers for this. In your GET Create action, put the available Customers and Items in to ViewData, and then in your view put some controls for the user to select values.
Then they will be POSTed to your POST Create action, and you can bind & save it in your Order object. You could have a separate action for adding Items to the Order if that gets too complex. But it could still be on the same OrdersController.