This article is about how to use versatile D3.js with Octopress.
Recently I was looking for flow chart diagram or tree structure diagram, but I did not want to produce static image diagrams using Microsoft Vizio or similar softwares.
My requirement was to come up with tree structure data representation, which I could change in future unlike static pictures and can not be changed in future.
I found D3.js to be perfect for this scenario. Here, I store data in JSON file and I use D3.js to display that data according to my needs.
Challenge was how to fuse D3.js with Octopress.
First approcah to understand the D3.js from scratch but since I was short in time so I choose hacker way.
D3.js have long list of examples/gallery which are extremly helpful and powerful.
In this blog I am trying to incorporate this example.
Step 1New post in Octopress created as .markdown file using
rake new_post [“D3.js and Octopress”]
This markdown file will now need to have have
- CSS - D3.js related stylesheet code for styling
- Javascript code - D3.js code to interpret data and bind with style sheet code
- JSON data file - This is going to be data file apart from .markdown file
JSON data file need to be placed in a folder from where it can be extracted when final html rendering is done.
I have choosen JSON file location to be
/assets/flare.json
d3.json(“/assets/flare.json”, function(json) {Here, assets folder for octopress is
> octopress -> /source/assets
JSON file can be found here
In below code snippet confiure following parameters to customize height and width of tree
h = 650 - m[0] - m[2] (replace 650 with 800 for expanded tree)
// Normalize for fixed-depth.
nodes.forEach(function(d) { d.y = d.depth * 130; }); ===> (Use 180 instead of 130 for wider tree)
// Initialize the display to show a few nodes.
root.children.forEach(toggleAll);
toggle(root.children[1]);
toggle(root.children[1].children[2]);
toggle(root.children[5]); =====> Here is number of 1st level childs
toggle(root.children[5].children[0]);
[Update] To make each node a hyperlink comment following code and instead insert below code.
Make sure JSON file have a field name url
// nodeEnter.append(“svg:text”)
// .attr(“x”, function(d) { return d.children || d._children ? -10 : 10; })
// .attr(“dy”, “.35em”)
// .attr(“text-anchor”, function(d) { return d.children || d._children ? “end” : “start”;
// .text(function(d) { return d.name; })
// .style(“fill-opacity”, 1e-6);
nodeEnter.append(“svg:a”).attr(“xlink:href”, function(d) { return d.url; }).attr(“target”, “_blank”)
.append(“svg:text”).text(function(d) { return d.name; })
.attr(“x”, function(d) { return d.children || d._children ? -10 : 10; })
.attr(“dy”, “.35em”)
.attr(“text-anchor”, function(d) { return d.children || d._children ? “end” : “start”; })
.text(function(d) { return d.name; })
.style(“fill-opacity”, 1e-6);
Code for blog post (.markdown file) is as follows
<script src="http://d3js.org/d3.v3.min.js"></script> <style type="text/css"> .node circle { cursor: pointer; fill: #fff; stroke: steelblue; stroke-width: 1.5px; } .node text { font-size: 11px; } path.link { fill: none; stroke: #ccc; stroke-width: 1.5px; } </style> <style> #chart, #header, #footer { position: absolute; top: 0; } #header.inverted, #footer.inverted { color: #fff; text-shadow: 0 1px 4px #000; } rect { fill: none; pointer-events: all; } line { stroke: #000; stroke-width: 1.5px; } .string, .regexp { color: #f39; } .keyword { color: #00c; } .comment { color: #777; font-style: oblique; } .number { color: #369; } .class, .special { color: #1181B8; } </style> <body> <div id="body"> click or option-click to expand or collapse </div> <script type="text/javascript"> var m = [20, 120, 20, 120], w = 1280 - m[1] - m[3], h = 650 - m[0] - m[2], i = 0, root; var tree = d3.layout.tree() .size([h, w]); var diagonal = d3.svg.diagonal() .projection(function(d) { return [d.y, d.x]; }); var vis = d3.select("#body").append("svg:svg") .attr("width", w + m[1] + m[3]) .attr("height", h + m[0] + m[2]) .append("svg:g") .attr("transform", "translate(" + m[3] + "," + m[0] + ")"); d3.json("/assets/flare.json", function(json) { root = json; root.x0 = h / 2; root.y0 = 0; function toggleAll(d) { if (d.children) { d.children.forEach(toggleAll); toggle(d); } } // Initialize the display to show a few nodes. root.children.forEach(toggleAll); toggle(root.children[1]); toggle(root.children[1].children[2]); toggle(root.children[9]); toggle(root.children[9].children[0]); update(root); }); function update(source) { var duration = d3.event && d3.event.altKey ? 5000 : 500; // Compute the new tree layout. var nodes = tree.nodes(root).reverse(); // Normalize for fixed-depth. nodes.forEach(function(d) { d.y = d.depth * 130; }); // Update the nodes… var node = vis.selectAll("g.node") .data(nodes, function(d) { return d.id || (d.id = ++i); }); // Enter any new nodes at the parent's previous position. var nodeEnter = node.enter().append("svg:g") .attr("class", "node") .attr("transform", function(d) { return "translate(" + source.y0 + "," + source.x0 + ")"; }) .on("click", function(d) { toggle(d); update(d); }); nodeEnter.append("svg:circle") .attr("r", 1e-6) .style("fill", function(d) { return d._children ? "lightsteelblue" : "#fff"; }); nodeEnter.append("svg:text") .attr("x", function(d) { return d.children || d._children ? -10 : 10; }) .attr("dy", ".35em") .attr("text-anchor", function(d) { return d.children || d._children ? "end" : "start"; }) .text(function(d) { return d.name; }) .style("fill-opacity", 1e-6); // Transition nodes to their new position. var nodeUpdate = node.transition() .duration(duration) .attr("transform", function(d) { return "translate(" + d.y + "," + d.x + ")"; }); nodeUpdate.select("circle") .attr("r", 4.5) .style("fill", function(d) { return d._children ? "lightsteelblue" : "#fff"; }); nodeUpdate.select("text") .style("fill-opacity", 1); // Transition exiting nodes to the parent's new position. var nodeExit = node.exit().transition() .duration(duration) .attr("transform", function(d) { return "translate(" + source.y + "," + source.x + ")"; }) .remove(); nodeExit.select("circle") .attr("r", 1e-6); nodeExit.select("text") .style("fill-opacity", 1e-6); // Update the links… var link = vis.selectAll("path.link") .data(tree.links(nodes), function(d) { return d.target.id; }); // Enter any new links at the parent's previous position. link.enter().insert("svg:path", "g") .attr("class", "link") .attr("d", function(d) { var o = {x: source.x0, y: source.y0}; return diagonal({source: o, target: o}); }) .transition() .duration(duration) .attr("d", diagonal); // Transition links to their new position. link.transition() .duration(duration) .attr("d", diagonal); // Transition exiting nodes to the parent's new position. link.exit().transition() .duration(duration) .attr("d", function(d) { var o = {x: source.x, y: source.y}; return diagonal({source: o, target: o}); }) .remove(); // Stash the old positions for transition. nodes.forEach(function(d) { d.x0 = d.x; d.y0 = d.y; }); } // Toggle children. function toggle(d) { if (d.children) { d._children = d.children; d.children = null; } else { d.children = d._children; d._children = null; } } </script> </body>
Demo
click or option-click to expand or collapse