I am using the Play framework in Scala to develop a small blog website. I currently have a form (successfully) set up for an easy registration of users. This login page just accepts a username (ie. no password yet), verifies that is of the appropriate length and doesn't exist yet, and adds this user to the database (currently still in memory). Length can be verified using just the basic form functionality, however, the uniqueness of this username required me to use custom validations.
Now, this all works, except for the custom error message. When a normal form requirement is not fulfilled, an error message is returned and displayed in the view (eg. "The minimum length is: 5"). I want to display a similar message when the name is not unique. In the first link I provided there is an example of custom validations which seems to have an argument that represents such custom error message for validations you write of your own. However, this does not display in the view, while the others do.
Current validation code:
private val myForm: Form[Account] =
Form(mapping("name" -> text(3, 24))(Account.apply)(Account.unapply).verifying(
"Account is not in the DB.",
fields =>
fields match {
case data: Account => accountExists(data.name).isDefined
}
)
)
Anyone has any ideas?
Related
I am currently programming a REST service and a website that mostly uses this REST service.
Model:
public class User {
private String realname;
private String username;
private String emailAddress;
private String password;
private Role role;
..
}
View:
One form to update
realname
email address
username
Another form to update the role
And a third form to change the password
.
Focussing on the first view, which pattern would be a good practice?
PUT /user/{userId}
imho not because the form contains only partial data (not role, not password). So it cannot send a whole user object.
PATCH /user/{userId}
may be ok. Is a good way to implement it like:
1) read current user entity
2)
if(source.getRealname() != null) // Check if field was set (partial update)
dest.setRealname(source.getRealname());
.. for all available fields
3) save dest
POST /user/{userId}/generalInformation
as summary for realname, email, username
.
Thank you!
One problem with this approach is that user cannot nullify optional fields since code is not applying the value if (input is empty and value) is null.
This might be ok for password or other required entity field but for example if you have an optional Note field then the user cannot "clean" the field.
Also, if you are using a plain FORM you cannot use PATCH method, only GET or POST.
If you are using Ajax you might be interested in JSON Merge Patch (easier) and/or JavaScript Object Notation (JSON) Patch (most complete); for an overview of the problems that one can find in partial updates and in using PATCH see also this page.
A point is that a form can only send empty or filled value, while a JSON object property can have three states: value (update), null (set null) and no-property (ignore).
An implementation I used with success is ZJSONPATCH
Focussing on the first view, which pattern would be a good practice?
My suggestion starts from a simple idea: how would you do this as web pages in HTML?
You probably start from a page that offers a view of the user, with hyperlinks like "Update profile", "Update role", "Change password". Clicking on update profile would load an html form, maybe with a bunch of default values already filled in. The operator would make changes, then submit the form, which would send a message to an endpoint that knows how to decode the message body and update the model.
The first two steps are "safe" -- the operator isn't proposing any changes. In the last step, the operator is proposing a change, so safe methods would not be appropriate.
HTML, as a hypermedia format, is limited to two methods (GET, POST), so we might see the browser do something like
GET /user/:id
GET /forms/updateGeneralInformation?:id
POST /updates/generalInformation/:id
There are lots of different spellings you can use, depending on how to prefer to organize your resources. The browser doesn't care, because it's just following links.
You have that same flexibility in your API. The first trick in the kit should always be "can I solve this with a new resource?".
Ian S Robinson observed: specialization and innovation depend on an open set. If you restrict yourself to a closed vocabulary of HTTP methods, then the open set you need to innovate needs to lie elsewhere: the RESTful approach is to use an open set of resources.
Update of a profile really does sound like an operation that should be idempotent, so you'd like to use PUT if you can. Is there anything wrong with:
GET /user/:id/generalInformation
PUT /user/:id/generalInformation
It's a write, it's idempotent, it's a complete replacement of the generalInformation resource, so the HTTP spec is happy.
Yes, changing the current representation of multiple resources with a single request is valid HTTP. In fact, this is one of the approaches described by RFC 7231
Partial content updates are possible by targeting a separately identified resource with state that overlaps a portion of the larger resource
If you don't like supporting multiple views of a resource and supporting PUT on each, you can apply the same heuristic ("add more resources") by introducing a command queue to handle changes to the underlying model.
GET /user/:id/generalInformation
PUT /changeRequests/:uuid
Up to you whether you want to represent all change requests as entries in the same collection, or having specialized collections of change requests for subsets of operations. Tomato, tomahto.
I have an entity Company and Address that have their own types CompanyType and AddressType. The AddressType is embedded in CompanyType. I did everything exactly the same as in Embedded Forms cookbook entry. The form is embedded correctly and is showing exactly as it should but validation is not working. I use separate .yml files for validation like this...
$yamlMappingFiles = $container->getParameter('validator.mapping.loader.yaml_files_loader.mapping_files');
$yamlMappingFiles[] = __DIR__.'/../Resources/config/validation/address_validation.yml';
$yamlMappingFiles[] = __DIR__.'/../Resources/config/validation/company_validation.yml';
$container->setParameter('validator.mapping.loader.yaml_files_loader.mapping_files', $yamlMappingFiles);
... and it is not validating in any of the entities. I tried corrupting the yml files and the parser throws an error which means that it loads the files. I also tried viewing var_dump($form->getErrors()); but it returns an empty array. At the same time, if i leave all blank fields in forms, the form isn't validated. Code is not entering here...
if( $form->isValid() ) {
... does not enter here if all input elements are empty ...
}
If I'm not mistaken, if no validation is used on a form, the form is always valid, so this must mean that validation .yml files are processed.
I didn't post any code beacuse my form is exactly the same as in the cookbook example. Just imagine that Task is Company and Tag is Addres.
Any ideas?
I'm currently trying to connect an Extjs form to a Play! Scala backend.
I have no problem receiving the request, but
FormName.bindFromRequest.get returns to me None .
I'm able to find the data generated via submitting from Extjs in the POST request in request.request.body.data (the first request object is generated by SocialSecure's controller), whereas normally the data bound to the form would be found in request.request.body.data.elems
I think Extjs's eschewal of using <form> in their inserted HTML is what causes me this problem, but I'd still like to take advantage of Extjs's nice form verification UI.
Does Play! or Scala have any resources for modifying a request after the server has received it?
More info
This is the method my /requestAudit cuurently points to after a POST request:
def requestAudit = SecuredAction(WithProvider("google")) { // SecureSocial syntax
implicit request => { // let's call this line 0'
println(request.request.body.asFormUrlEncoded) // let's call this line 1'
println(request.body.asText) // let's call this line 2'
newAuditForm.bindFromRequest.fold(
errors => BadRequest(views.html.error(newAuditForm))
success => { /*insert the object into my db*/ }
) } }
Ext.js request
When I'm debugging in Eclipse with an Ext.js form, the Variables window shows: (click for closeup)
where the form values are located in request.body.data.key1, request.body.data.key2, etc
Bootstrap form request
On the other hand, the request for Bootstrap has the values stored in request.body.data.elems
#2manyprojects 's suggestion set me on the right path:
newAuditForm.bindFromRequest(
(request.request.body.asFormUrlEncoded).getOrElse(Map()))
.fold( ... )
worked.
I was still getting form binding errors after changing my code to this, and then I discovered a typo in the name property of one of my Ext.js form fields. The name of the field must be the same on both the UI and the Play Form.
I have a Drupal 7 form where after submitting it, some validation happens. It is taking the email address and doing a database look-up to see if that user already exists. If the user exists, I need to alter the form that re-renders on the page that normally displays the errors, removing some fields. Basically on the error page, regardless of any other validation errors they would have normally received (First name required, last name required etc.) they would only get one error message that says "that email address is already in the system" and then I no longer want to display ANY of the other fields at this point except the email address field and a file upload field. So I'm having trouble trying to figure out how to alter the form after the first submission based on some validation.
Thanks
What you want to do is add some data to the $form_state variable in your validation function that can inform your form function as to what fields it should provide.
Untested Example:
function my_form($form, &$form_state){
$form['my_field1'] = array('#markup' => 'my default field');
// look for custom form_state variable
if ($form_state['change_fields']) {
$form['my_field2'] = array('#markup' => 'my new field');
}
}
function my_form_validate($form, &$form_state){
// if not valid for some reason {
form_set_error('my_field1','this did not validate');
$form_state['change_fields'] = true;
// }
}
I'm taking the Lift basic example project for 2.5-M3 and want to adapt
it for Record and Mongo.
It all works fine except when I try to sign up the generated form
only has one password field and no repeated field. When filling that
one field I get an error message "Passwords do not match".