I am trying to do validations in struts 2 for my current project. I have to group my validation messages. For Eg: If there are 3 fields that are empty and there are 3 other fields whose format is not right, I need to get a msg like
"The following fields are required: field1, field2, field3
The format of the following fields are invalid: field4, field5, field6"
I tried providing a param to fieldError.
Eg:
< s : fielderror >
< s : param value="%{requiredstring}"/>
< / s : fielderror>
According to me this is like specifying "show all errors whose validator type is requiredstring". Please correct me if I am wrong.
But this will display the message "The following fields are required" each time for every field that is empty. I want it displayed only once.
Is there a way to do this cleanly in stuts2 using validation through xml? I donot want to do all the validations in a validate method.
Thanks
You are wrong; I have no idea why you thought that'd work, the docs don't imply that's possible.
Field errors are just that--errors for a specific field. If you need to group errors by arbitrary criteria, like the validation type, you'll need to implement that yourself.
There are a number of ways to do this, including writing a custom validation interceptor, providing validators that group errors in a different way, or simply gathering the appropriate messages in an action or validation method.
You could gather errors based on the message content, but IMO that would be brittle. If this is a cross-application issue, you're better off doing it a different way.
All that said, by presenting error messages in an order not necessarily reflective of the form, you're pushing more cognitive overhead onto the user: I don't want to see groups of messages telling me which fields share the same error, I want to see what's wrong with each field, in the same order the fields are presented on the form, preferably near the form field itself.
Related
In Laravel form validation you can do this: file_description.* to validate each item of an array according to a set of rules. The problem is, the system automatically returns "file_description.1 is required" as an error message if the field is required and not filled in.
More on that here: https://ericlbarnes.com/2015/04/04/laravel-array-validation/
Now, I'm not a complex man, I just want the field to say "File Description 1 is required". I am aware you can set messages but a) my input arrays are dynamically generated by jquery (click to add more type scenario) so I'd have to use a loop like in the above example b) I feel like there must be a better way.
Is there a way to either extend the core validation system to simply return a humanized name for the array field as Laravel does with regular fields, or is there an option I missed in the docs that allows for this? I'd rather not get involved with doing some regex type search to fix this.
I built two custom components using built-in CQ components. The components' JSP's, along with some custom javascript, have a line like below in order to leverage the built-in components (and their formatting, labels, etc.).
<cq:include path="." resourceType="foundation/components/form/dropdown" />
I have one each of my custom dropdown components on a form. I can mark field A and field B as both being required in their respective components' editor dialog. I can provide required messages so that when either field is blank and the form is submitted, I get a message that the fields are required (with my custom messages). However, what I really want to do is hide or disable field B based on the value supplied in field A. I'm handling this manually via jQuery. However, this of course presents a problem on validation. I want field B to be NOT required when it is hidden/disabled and for it to be required when it is enabled/visible. Since the showing/hiding is done client-side, the server-side validation has know knowledge of the change and still expect a value to be provided for field B.
I'm been trying to poke around in the CQ Widgets API to find if there is something I can do on the client side to set/unset the required property so that when the form gets posted it is handled correctly. I'm guessing that there isn't since the validation seems to be happening on post instead of client-side.
Any ideas/thoughts/options?
It turns out that the link from my comment gave me the idea that I can have custom server-side validation for my form, I just wasn't sure how to connect it to the field. It turns out that all I had to do was create a servervalidation.jsp file in my "B" component. CQ will see the servervalidation.jsp and automatically invoke it for my custom component.
I was then able to examine the submitted value of field "A" (by getting the parameter from the request object) and doing some other custom logic for my needs.
I was then able to optionally do this:
FieldDescription field = FieldHelper.getConstraintFieldDescription(slingRequest);
FieldHelper.checkRequired(slingRequest, field);
I am in reference to the following method from BindingResult:
BindingResult.html#resolveMessageCodes(java.lang.String, java.lang.String)
I am trying to figure out the difference between an error code and a message code. Can someone please provide an example, especially one that would illustrate why there could be several message codes for a given error code?
Because web applications are internationalized, when you reject an object and want to have a message displayed for it, you don't use a hardcoded text because that will show the same no matter the language.
Instead, you specify an error code that later server as a key to retrieving the proper message from the bundles (and now the error code is a message code from the point of view of the method that must find the proper message text).
Your error code resolves to more message codes because Spring (based on the implementation) adds some additional ones for you. Here is a snippet from the Spring documentation:
[...] What error codes it registers is determined by the MessageCodesResolver that is used. By default, the DefaultMessageCodesResolver is used, which for example not only registers a message with the code you gave, but also messages that include the field name you passed to the reject method. So in case you reject a field using rejectValue("age", "too.darn.old"), apart from the too.darn.old code, Spring will also register too.darn.old.age and too.darn.old.age.int (so the first will include the field name and the second will include the type of the field); this is done as a convenience to aid developers in targeting error messages and suchlike. [...]
The last statement is the reason there are more message codes, to have control on the message that is displayed to the user, from a generic one (e.g. "Value required") to a more specific one given the context (e.g. "A value is required for field XXX").
The javadoc for DefaultMessageCodesResolver explains it further and gives an example:
For example, in case of code "typeMismatch", object name "user", field "age":
try "typeMismatch.user.age"
try "typeMismatch.age"
try "typeMismatch.int"
try "typeMismatch"
This resolution algorithm thus can be leveraged for example to show specific messages for binding errors like "required" and "typeMismatch":
at the object + field level ("age" field, but only on "user");
at the field level (all "age" fields, no matter which object name);
or at the general level (all fields, on any object).
I realize this is kind of "Stripes 101", but I guess I skipped that class.
I'd like to use the code that drops the "error" class into the field
tag class strings as the primary way to indicate missing required
fields. I'd then like to show a single error message along with any
other errors (like fields supplied with improper values).
Thus, the error info on the page might look like:
Sorry for the trouble, but:
1. Please supply values for all indicated required fields.
2. Please supply a numeric value for Zip Code.
etc.
I suppose I could go through the validation errors, look for ones for
fields where the value is empty, and make the assumption that those
were the required field errors. However, if I take those errors out
of the set, then I suspect that the page will no longer be able to
mark the erroneously-missing fields with the "error" class.
This seems like something likely to be pretty easy, but I can't find
any specific examples. Maybe I can do it all in the .jsp code; I'll start looking into that.
The DefaultActionBeanPropertyBinder adds an instance of ScopedLocalizableError with the default scope value of "validation.required" when a required field is missing.
So you coult probably write a tag similar to the stripes errors tag, but which collapes all the instances of ScopedLocalizableError having a default scope of "validation.required" to a single error message.
A simple question: I have a Model-View-Controller setup, with Models accessing a SQL database. In which part should I sanitize/check for malformed incoming data?
It's important to keep error handling as low as possible in the stack, but supplemental in other parts. If you keep the sanitizing in the controller, you could break the model by swapping out the controller with a looser one, but you can never break the model by being strict higher up in the stack. Keep the sanitizing low in the stack for consistency, and high in the stack for user feedback.
I'd say the Controller should sanitize input.
The model should at most decline to store invalid data.
I would say it is the responsibility of the controller to validate the input and make sure the data is valid before passing on the data to the model.
If invalid data is found, the controller should redirect back to the view and display the relevant error messages.
Having validation in the view only could be bypassed if the user doesn't have javascript enabled or posts to the url directly, however some validation in the view is better from a user experience point of view since the user does not need to wait for a return from the server in a web application.
The model will validate business logic rules, i.e. password length requirements, if a user is allowed to perform an action or not.
The model should obviously also make sure interaction with the database is done in a safe way so that SQL Injection is not possible.
The controller should handle relaying business logic errors back to the view, but can also do some basic sanity checks, i.e. a field is not empty.
I would say output sanitization should also go in the Controller before being passed to the View.
I use two levels of checking. My controller will check what is supposed to be a date is a date, an int an int and so forth. Basically ensuring they can be used to set the values on my objects.
Then my domain has validation for things such as valid values and other business rules. These are ALWAYS checked before saving or interacting with an edited object.
All errors from either level get returned to the user so they can take remedial action as necessary.
I tend to:
Put syntactic validation in the view ("this field is numeric", "that field is a date"). This is often very easy or even implicit in your choice of view design (eg: using a date picker for date fields).
Put semantic violation in a separate validator class ("this date field has to be after that date field", "this can be null if that is greater than zero") and call the validator from the controller, passing errors back to the view for display.
(for my own pseudo-correct definitions of syntax and semantics...)