[Grails] Passing user object into hiddenField

[Karol Litwinczuk]

Hello!

I wirte my first, simple app emulating the gaming review portal. What I have problem with is that I have Reviews domain class that belongs to Person class ( as author of review ) genrated from Acegi Plugin ( both clases listed below ). When I want to create new Review, the app says many things, bnut mainly this error massage:

Failed to convert property value of type java.lang.String to required type Person for property author; nested exception is java.lang.IllegalStateException: Cannot convert value of type [java.lang.String] to required type [Person] for property autor: no matching editors or conversion strategy found

I want the app to take and use Acegi loggedInUserInfo(field:'username') variable, to give reviews proper author users, of course, as hiddenField. Could someone help me?

class Person {
	static transients = ['pass']
	static hasMany = [authorities: Authority, reviews: gameaddict.Reviews, comments: gameaddict.Comment ] // Every user can add many reviews nad many comments
	static belongsTo = Authority
        /** Username */
	String username
	/** User Real Name*/
	String userRealName
	/** MD5 Password */
	String passwd
	/** enabled */
	boolean enabled

	String email
	boolean emailShow

	/** description */
	String description = ''

	/** plain password to create a MD5 password */
	String pass = '[secret]'

	static constraints = {
		username(blank: false, unique: true)
		userRealName(blank: false)
		passwd(blank: false)
		enabled()
	}

        String toString(){
        username
        }
}

package gameaddict

class Review {
    static hasMany = [ comments: Comment ]
    static belongsTo = [author: Person]
    String title
    Date dateCreated
    Date lastUpdated
    String tresc

    static mapping = {
        tresc type: "text"
    }

    static constraints = {
        title()
        author()
        tresc(maxSize:50000)
        dateCreated()
        lastUpdated()
    }   
   
}

And here is the part of Review/Create view tha is resposible for taking the Author but is not working:

<tr class="prop">
                                <g:select name="author" from="${Person.list()}" optionKey="id" value="${reviewInstance?.author?.id}" />
                            </tr>
                        

[Kuba Zygmunt]

Hi Karol,

What about using hidden field for person id and then in submit action load the proper user object which you can use later in your review.

If you want to send the object through the form you will have to serialize and deserialize after.However this approach is not so secure, because user can modify the object before submission.


Jakub

[Karol Litwinczuk]

Kuba Zygmunt wrote:
What about using hidden field for person id and then in submit action load the proper user object which you can use later in your review.

I never mixed something like that in Grails - could you propose how this code should look like or at least give some function names to read more in manual?

Kuba Zygmunt wrote:
If you want to send the object through the form you will have to serialize and deserialize after.However this approach is not so secure, because user can modify the object before submission.

Well, it's only the learning app, so can be much more easier but can't you serialize data and then secure them by, I don't know, md5 for example?

[Kuba Zygmunt]

I will try to make an example:

// review controller

def showForm = {
  def person = ... // get a person object from Acegi
  def reviewInstance = new Review()
  reviewInstance.properties = params
  
  [ reviewInstance: reviewInstance, personId : person.id ]
}

def saveReviewForm = {
  // load a person
  def person = Person.get(params.personId)

  // do all the rest with review Form
  ...
}

and in view

<g:jiddenField name="personId" value="$personId" />

in this case you save the bandwidth, you send only small int instead of the serialized object.

[Karol Litwinczuk]

Kuba Zygmunt wrote:

def showForm = {
  def person = ... // get a person object from Acegi

How could this be? WIth usage of loggedInUserInfo(field:'username')? Or maybe some SQL query? I never get taking session params...

[Kuba Zygmunt]

If you match person witch acegi user by username, then you can find person using GORM

  def person = Person.findByUsername(usernameFromAcegi)   

BTW you can get information from acegi anytime so there is no need to pass user information, just find a proper person before you save a review

[Karol Litwinczuk]

I got idea just to remade Save function in Review ( Recenzja in polish ), but it doesn't work. Here is my code:

 
def save = {
        def person = Person.findByUsername(loggedInUserInfo(field:'username'))
        def recenzjaInstance = new Recenzja(params)
        if (recenzjaInstance.save(flush: true)) {
            flash.message = "${message(code: 'default.created.message', args: [message(code: 'recenzja.label', default: 'Recenzja'), recenzjaInstance.id])}"
            redirect(action: "show", id: recenzjaInstance.id)
        }
        else {
            render(view: "create", model: [recenzjaInstance: recenzjaInstance, autor: person.id])
        }
    }
   

And here is error:

Error 500: Executing action [save] of controller [gameaddict.RecenzjaController] caused exception: No such property: Person for class: gameaddict.RecenzjaController Possible solutions: session
Servlet: grails
URI: /GameAddict/grails/recenzja/save.dispatch
Exception Message: No such property: Person for class: gameaddict.RecenzjaController Possible solutions: session
Caused by: No such property: Person for class: gameaddict.RecenzjaController Possible solutions: session
Class: RecenzjaController
At Line: [24]

Any ideas on that?

[Kuba Zygmunt]

check packages and if controller and domain class are in different packages use import.

[Karol Litwinczuk]

Kuba Zygmunt wrote:check packages and if controller and domain class are in different packages use import.

The tree is like this:

/main-app-folder/...
/gameaddic/ Reviews
Person
...

That means that Controller of Review IS in package ( gameaddict ), but Person is in main folder of app ( in this case, in Controllers ) - how to make import to controller in package from main folders of app. Shouldn't they be ready to use in whole app, as they are in main controllers?

[Kuba Zygmunt]

Hi

if you use grails version 1.3.1 or newer then your domain classes will be in package named by your application. It is always better to use packages

[Karol Litwinczuk]

Kuba Zygmunt wrote:Hi

if you use grails version 1.3.1 or newer then your domain classes will be in package named by your application. It is always better to use packages

I use the packages. The problem is that I don't kno how to import class of Person that is otuside of app package into Review that is inside the package.

[Kuba Zygmunt]

hi it looks like your structure is a bit messed up.

try to sort out your folders like :

<appname>
  grails-app
    conf
    controllers
      <appname or other package name>
        ReviewController.groovy
    domain
      <appname or other package name>
           Review.groovy
            Person.groovy
  lib
  out
  scripts
  src
    groovy
      <some ohter packages>
          SomeClass.groovy
  target
  test
  ...

if you have a domain class put it in grails-app/domain/<package> like Review and Person .
If you want to have some classes which are not domain classes put them in src/groovy/<package>/

then you can import them in grails using import <package-name>.<className>

Regards

[Karol Litwinczuk]

Unfortunetly, this doesn't work. Any other ideas? Th a main porblme is that Revies controller can't find the Perrsons obcjet, even where Persons Class are in the same packages.

[Kuba Zygmunt]

It's hard to tell, so if you could pack your grails-app, put somewhere, and provide a link ( through forum or PM ), then I could check it for you.

Jakub

--edit
I reviewed your files and couple of things you could improve.

1. Put 3 classes created by Acegi plugin into package 'gameaddict' or 'security' or even 'gameaddict.security' ( yours grail app ) so you wont have problems with finding them later. You can use a command like

grails create-auth-domains gameaddict.security.Person gameaddict.security.Authority gameaddict. security.Requestmap

2. to get info in controller about current user, add authenticateSerive and then use userDomain() method. eg.

def authenticateService
...

def save = {
        def recenzjaInstance = new Recenzja(params)
        def person = authenticateService.userDomain()
        if (person) {
          recenzjaInstance.autor = person
          // jesli nie bedzie autora to ci nie  zapisze obiektu
        }
        if (recenzjaInstance.save(flush: true)) {
            flash.message = "${message(code: 'default.created.message', args: [message(code: 'recenzja.label', default: 'Recenzja'), recenzjaInstance.id])}"
            redirect(action: "show", id: recenzjaInstance.id)
        }
        else {
            render(view: "create", model: [recenzjaInstance: recenzjaInstance, autor: person.id])
        }
}

I hope it helps

Jakub