How to improve typeAhead performance on xPage?

Question

Here is my inputText control with typeAhead enabled:

<xp:inputText id="inputNameEditBox">
    <xp:typeAhead 
        mode="full" 
        minChars="3"        
        ignoreCase="true"
        valueList="#{javascript:return mytypeAheadList();}"
        var="searchValue" 
        valueMarkup="true" 
        id="typeAhead1">
    </xp:typeAhead>
</xp:inputText>

SSJS mytypeAheadList() function calls custom Java userTools.userLookup() function to get a set of suggestions. (Our server cannot access corporate directory so we have to use LDAP HTTP Java API).

SSJS library:

function mytypeAheadList(){
    var v=new userTools.userLookup();  //Java library
    var usrList = v.getUserList(searchValue);
    var lenList = usrList.length;
    var retList = "<ul>";

    if(lenList>0){
        for (var i=0; i<lenList; i++) { 
            var matchDetails:string = ["<li>",@Name("[ABBREVIATE]", @Left(usrList[i], "@")),"</li>"].join(""); 
            retList += matchDetails;
        }       
    } else {
        retList += ["<li>","None found","</li>"].join("");
    }

    retList += "</ul>"; 
    return retList;     
}

So that means userTools Java object is created each time user type a character. Is there a way to avoid it, e.g. make var v a global variable on page load? Seems scope variables cannot accept Java objects.

Sven Hasselbach Sven Hasselbach · Accepted Answer · 2017-02-01T07:40:49

I would do the following:

Implement the Serializable interface to your POJO returned by getUserLookup. This allows to store the object in viewScope
Limit the max size of lenlist. E.g. 20 results would reduce the time of looping, the size of the HTTP response and the performance in the browser
Cache the result of the search (add searchValue and the resulting HTML string to a map). If a user hits backspace, the whole result must not be recomputed.
Drop SSJS. Use Java.
optional: If possible, precompute the results.

EDIT Something like this:

function mytypeAheadList(){

    // check if value is already cached
    if( viewScope.containsKey("search~" + searchValue) ){
        return viewScope.get("search~" + searchValue);
    }

    // get the userLookup object
    var v = null;   
    if( viewScope.containsKey("userLookup") ){
        v = viewScope.get("userLookup");
    }else{
        v = new userTools.userLookup();
        viewScope.put("userLookup", v);
    }

    // if usrList is "unlimited", limit the max size
    var usrList = v.getUserList(searchValue);
    var lenList = usrList.length > 20 ? 20 : usrList.length;

    // if getUserList has a restriction parameter
    var usrList = v.getUserList(searchValue, 20);
    var lenList = usrList.length;

    // build the list
    var retList = null;

    // reuse a variable is up to 2 times faster
    var matchDetails = null;

    if(lenList>0){
        retList = "<ul>";
        for (var i=0; i<lenList; i++) { 
            // concatenating a string is up to 2 times faster then join
            matchDetails = "<li>" + @Name("[ABBREVIATE]", @Left(usrList[i], "@")) + "</li>";
            retList += matchDetails;
        }
        retList += "</ul>"; 
    } else {
        // why join a static string?
        retList = "<ul><li>None found</li></ul>";
    }


    // put the result to the cache
    viewScope.get("search~" + searchValue, retList);

    return retList;     
}

How to improve typeAhead performance on xPage?

2 Answers