dg-jsplumb.js

// based on http://onais-m.blogspot.nl/2014/10/automatic-graph-layout-with-javascript.html
var jsp = jsPlumb.getInstance();

// construct dagre graph from JsPlumb graph
/* global dagre */
var g = new dagre.graphlib.Graph();
g.setGraph({nodesep:30,ranksep:30,marginx:50,marginy:50});
g.setDefaultEdgeLabel(function() { return {}; });

$('.xnode').each(
  function(idx, node) {
    var n = $(node);
    g.setNode(n.attr('id'), {
      width  : Math.round(n.outerWidth()),
      height : Math.round(n.outerHeight())
    });
  }
);

jsp.getAllConnections().forEach(
  function(edge) {
    g.setEdge(
      edge.source.id,
      edge.target.id
    );
  });

// calculate the layout (i.e. node positions)
dagre.layout(g);

// Applying the calculated layout
g.nodes().forEach(
  function(n) {
    var node = dg.node(n);
    var top = Math.round(node.y-node.height/2)+'px';
    var left = Math.round(node.x-node.width/2)+'px';
    $('#' + n).css({left:left,top:top});
  });

jsp.repaintEverything();

dagre+jsPlumb+jquery,panzoom live demo here