dust.js format text through a function

Question

dust.js format text through a function

I've got a javascript function which blur's text:

function blurlines(data) {
    var dataSplit = data.split(" ");
    var lastWord = dataSplit.pop();
    var toBlur = '<span class="blur">' + dataSplit.join(" ") +  '</span>'; 
// Blur entire sentace, show only last word
     var output = '<li>' + toBlur + lastWord + '</li>';
     return output;
}

I'm trying to get this to work with dust.js by trying something like:

{#storylines}
    <script>
        blurlines("{text}");
    </script>                   
{/storylines}

Is there anyway to easily pass the {text} value through a JS function and then render the output?

If i run it in console it seems to work:

> blurlines("This is a test line")

> "<li><span class="blur">This is a test</span>line</li>"

node.js
mongodb
express
socket.io
dust.js

Answer 1

I do something similar, create a helper function in my global context:

var dustCtx = dust.makeBase({
    blurText: function(chunk, context, bodies, params) { 
        var dataSplit = params.data.split(" ");
        var lastWord = dataSplit.pop();
        var toBlur = '<span class="blur">' + dataSplit.join(" ") +  '</span>'; 
        var output = '<li>' + toBlur + lastWord + '</li>';
        return chunk.write(output);
    }
});

Merge it with local context on render:

dust.render("template", dustCtx.push({storylines:...}), function(err, out) {});

And then call it like this:

{#storylines}
    {#blurText data=text/}
{/storylines}

This approach might be handy for passing additional parameters if you wanted to control the blurring for example.

Answer 2

I created a dust.js filter to get it to work

  bl: function(value){  var dataSplit = value.split(" ");
    var lastWord = dataSplit.pop();
    var toBlur = '<span class="blur">' + dataSplit.join(" ") +  '</span>'; 
     var output = toBlur + lastWord;
     return output; }

and am passing the below in the template:

{#storylines}
    <li>{text|bl|s}</li>    
{/storylines}