Automatically generate hints and alert messages

[ebruchez]

I thought we already had an RFE for this. Idea:

• default error message per datatype (xf:integer ⇒ "Must be a number")
• default error messages for common constraints

+1 from customer

[ebruchez]

+1 from customer for these examples:

File size must be less than {maxfilesize} MB.
File format is not allowed, allowed file formats are {fileformats}

And also for considering automatically-generated hints.

[ebruchez]

Specifically:

• built-in types
  • string (any string passes so this is a NOP)
  • boolean
  • xf:email
  • decimal
  • integer
  • date
  • time
  • dateTime
• common constraints
  • Maximum Length
  • Minimum Length
  • Positive
  • Positive or Zero
  • Negative or Zero
  • Negative
  • Maximum Fractional Digits
  • Maximum Attachment Size (new with #3122)
  • Allowed File Formats (new with #3122)

[ebruchez]

Right now:

• For errors, the UI has a checkbox to either pick a default error message ("Missing or incorrect value").
• For warning/info messages, a custom message has to be supplied and there is no default message.
• Form Builder places the following on <xf:alert ref="...>
  • Global default message: <xf:alert ref="$fr-resources/detail/labels/alert"/>
  • Control default message: <xf:alert ref="$form-resources/control-1/alert"/>
  • Custom message: <xf:alert ref="$form-resources/control-1/alert" validation="validation-6-validation"/>

I suggest the following changes:

• Default message changed from constant to dependant on the validation type and datatype:
  • Required validation (error)
    • "Value is required" or "Required value"
  • Data Type validation (error)
    • "value must be true or false"
    • "value must be an email"
    • "value must be a decimal number"
    • "value must be an integer number"
    • "value must be a date"
    • "value must be a time"
    • "value must be a date and time"
  • Common constraints (error)
    • "Value must not be longer than $maxlength"
    • "Value must not be shorter than $minlength"
    • "Number must be positive"
    • "Number must be positive or zero"
    • "Number must be negative or zero"
    • "Number must be negative"
    • "Number must have less than $maximumFractionalDigits fractional digits"
    • "Attachment must not be larger than $maxSize MB"
    • "Attachment must be be of one of the following types: $mediatypes"
      • exact display of types TBD
• Allow default messages for warning/info messages
  • for common constraints
  • but not for formulas

One question is how to point to the custom message. It must come down to, approximately:

xxf:format-message(
    $messageTemplate,
    (
        $parameterToTheConstraint
    )
)

Options:

• Form Builder could generate that XPath into the ref:
  • <xf:alert ref="xxf:format-message(...)"/>
  • not ideal as there is duplication which can be error-prone
• Form Builder places a generic function which does all the work:
  • <xf:alert ref="fr:alert-message()"/>
  • somehow this would mean the function would have access to the currently-failed contraint

[ebruchez]

Still current for customer.

[ebruchez]

We need an option to enable default hints:

• for some controls, it's obvious what the type is (for example currency), so a default hint might add undesired noise
• when you introduce custom validations ("value must be greater than x"), default hints become much more useful
• so this could be enabled by default for controls with constraints
• so need checkbox to say "show default hint" (like for )
• if the form author specifies a custom hint, that would override the default hint when enabled
  • but then we need to make sure that a custom hint can easily use the validation constraints, etc.

[ebruchez]

+1 from customer

[ebruchez]

For hints:

• [ ] ability to enable automatic hints for control, form, or via properties
  • [ ] in Hint tab, "Automatic hint": "Use default" / "Yes" / "No", and always let the user enter a "Custom hint"
  • [ ] consider combining custom hint if non-blank with automatic hint if present at runtime (pick an order)
• [ ] at runtime, determine for each control if an automatic hint must be generated, and do the magic
• [x] Q: How to convert for example application/pdf to .pdf.