How to use D3 in Node.js properly?

Question

I've been trying to invoke D3 within Node.js. I tried firstly to import d3.v2.js from D3's website with the script tag, but then read this thread:

Wanna run d3 from a Cakefile

Where D3's author advises one should 'npm install d3'...I did this, and I can successfully invoke it in node console:

dpc@ananda:$ node

> var d3 = require("d3");

undefined

> d3.version;

'2.8.1'

However, when trying to invoke it from app.js with 'node app.js', I get:

node.js:201

    throw e; // process.nextTick error, or 'error' event on first tick

          ^

TypeError: Cannot read property 'BSON' of undefined

at     /Users/dpc/Dropbox/sync/Business/MindfulSound/Development/nad.am/nadam/node_modules/mongoose/node_modules/mongodb/lib/mongodb/index.js:45:44

I realise that elsewhere, D3's author has clearly specified that one should require the canvas:

https://github.com/mbostock/d3/blob/master/examples/node-canvas/us-counties.js

as:

var Canvas = require("canvas");

but even then, (and even if specifically requiring index.js instead of d3.v2.js in a require statement in app.js), I can't get the below to work within a Jade template:

- script('/javascripts/d3.v2.js')

h1 Dashboard

  section.css-table

    section.two-column

      section.cell

        hr.grey

        h2 Statistics

        #mainGraph

            script(type="text/javascript") 

              var Canvas = require("canvas");

              var w = 400,

                  h = 400,

                  r = Math.min(w, h) / 2,

                  data = d3.range(10).map(Math.random).sort(d3.descending),

                  color = d3.scale.category20(),

                  arc = d3.svg.arc().outerRadius(r),

                  donut = d3.layout.pie();

              var vis = d3.select("body").append("svg")

                  .data([data])

                  .attr("width", w)

                  .attr("height", h);

              var arcs = vis.selectAll("g.arc")

                  .data(donut)

                  .enter().append("g")

                  .attr("class", "arc")

                  .attr("transform", "translate(" + r + "," + r + ")");

              var paths = arcs.append("path")

                  .attr("fill", function(d, i) { return color(i); });

              paths.transition()

                  .ease("bounce")

                  .duration(2000)

                  .attrTween("d", tweenPie);

              paths.transition()

                  .ease("elastic")

                  .delay(function(d, i) { return 2000 + i * 50; })

                  .duration(750)

                  .attrTween("d", tweenDonut);



              function tweenPie(b) {

                b.innerRadius = 0;

                var i = d3.interpolate({startAngle: 0, endAngle: 0}, b);

                return function(t) {

                  return arc(i(t));

                };

              }



              function tweenDonut(b) {

                b.innerRadius = r * .6;

                var i = d3.interpolate({innerRadius: 0}, b);

                return function(t) {

                  return arc(i(t));

                };



      section.cell

        hr.grey

        h2 Achievements

Answer 1

The correct way to use D3 within Node is to use NPM to install d3 and then to require it. You can either npm install d3 or use a package.json file, followed by npm install:

{
  "name": "my-awesome-package",
  "version": "0.0.1",
  "dependencies": {
    "d3": "3"
  }
}

Once you have d3 in your node_modules directory, load it via require:

var d3 = require("d3");

And that's it.

Regarding your other issues: Canvas is not required to use D3. The node-canvas example you linked requires canvas because it renders to a canvas. The TypeError (Cannot read property 'BSON' of undefined) appears to be related to your use of mongoose / monogdb, not D3.

How to use D3 in Node.js properly?

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