How do I prohibit double quotes in an inputText in XPages? - regex

Question

I've been trying to prohibit users from entering double-quotes (") into some fields that are used in JSON strings, as they cause unexpected termination of values in the strings. Unfortunately, while the regex isn't hard to write, I can't get it to work within XPages.
I tried using both double-quotes alone and using the escape character. Both ways fail any string, not just ones including the double-quotes.
<xp:validateConstraint message="Please do not use double quotes in organization/vendor names">
<xp:this.regex><![CDATA['^[^\"]*$]]></xp:this.regex>
</xp:validateConstraint>
There must be a simple way around this issue.

Answer 1

I think you're running into issues with your regex property for your xp:validateConstraint validator. You seem to be attempting to strip the characters in the xp:this.regex as opposed to specifying what characters are allowed, as I believe the docs read. I might recommend checking out the xp:customConverter (bias: I'm more familiar with the customConverter) which gives you the ability to alter the getValueAsObject and getValueAsString methods; then you can escape the undesired characters.
Here's what I'm thinking of, to strip them out. If you plug this into an XPage, you'll find that when the value is pulled (e.g.- by the partial refresh), it converts the input content accordingly by stripping out quotes (both single and double, in my case).
<?xml version="1.0" encoding="UTF-8"?>
<xp:view xmlns:xp="http://www.ibm.com/xsp/core">
<xp:inputTextarea
id="inputTextarea1"
value="#{viewScope.myStuff}"
disableClientSideValidation="true">
<xp:this.converter>
<xp:customConverter>
<xp:this.getAsString><![CDATA[#{javascript:return value.replace(/["']/g, "");}]]></xp:this.getAsString>
<xp:this.getAsObject><![CDATA[#{javascript:return value.replace(/["']/g, "");}]]></xp:this.getAsObject>
</xp:customConverter>
</xp:this.converter>
</xp:inputTextarea>
<xp:button
value="Do Something"
id="button1">
<xp:eventHandler
event="onclick"
submit="true"
refreshMode="partial"
refreshId="computedField1" />
</xp:button>
<xp:text
escape="true"
id="computedField1"
value="#{viewScope.myStuff}" />
</xp:view>
My interaction with the above code yields:
Notice that for it to reflect in the refresh, I'm modifying both the getAsString and the getAsObject, since it's updating the viewScope'd object during the refresh (a fact I had to remind myself of), but saving to a text field in XPages will get the value by the getAsString (provided your data source knows its a String related field, e.g.- NotesXspDocument as document1, with known Form, where the field is a Text field).
As the above comments alluded to, this performs an act of filtering the input values as opposed to escaping or validating those values. You could also change my replace methods to replacing with a text escape character, return value.replace(/"/g,"\"").replace(/'/g,"\'");.

Answer 2

Is the simple answer just add a JavaScript function call on the submit button to remove the quote?
A more elegant solution would be to not allow typing of the quote by checking the keydown event and preventing for that character code. The user should not be able to type one thing and then have it changed on them in processing

Answer 3

#Eric McCormick recommends a customConverter which in my opinion is a neat solution I probably would be going for in many cases. Sometimes however we need to teach users to adhere to the rules so we have to show them where they did wrong. That's when we may need a validator.
Playing around a bit the simplest solution I came up with is a xp:validateExpression simply looking for the first occurrence of a double quote within the String entered:
<xp:inputText
id="inputText1"
value="#{viewScope.testvalue}">
<xp:this.validators>
<xp:validateExpression
message="Hey, wait! Didn't I tell you not to use double quotes in here?">
<xp:this.expression><![CDATA[#{javascript:value.indexOf("\"")==-1}]]></xp:this.expression>
</xp:validateExpression>
</xp:this.validators>
</xp:inputText>
If that's a single occurrence in your application that's it, really. If you need this and similar solutions all over the place you might want to take a look into writing a small validator bean (java), register it via faces-config.xml and then use it everywhere in your application e.g by using an xp:validator instead

Answer 4

As suggested by #Tomalik and #sidyll, this is attempt to solve the wrong problem. While each of the answers supplied do solve the problem of preventing the user from entering undesirable characters, it is better to encode those characters to preserve the user's input. In this particular case, the intermediate step in providing the data to the user via a JSON string is to pull the value from a view.
So, all I had to do was change the column formula to encode the string using the UTF-8 character set and it displays the values with the "undesirable characters". The unencoded value is stored on the document so that Old Notes access won't create confusion.
#URLEncode ("UTF-8"; vendorName )
In one case, the JSON is computed as part of the form design, but the same solution works.