D3js save SVG file by wboykinm

index.html

<!DOCTYPE html>
<meta charset="utf-8">
<style>

    body {
        font: 10px sans-serif;
    }

    .axis path,
    .axis line {
      fill: none;
      stroke: #000;
      shape-rendering: crispEdges;
    }

    .area {
      fill: steelblue;
    }
</style>
<body>
<div id="chart"></div>
<button id="generate">Save as SVG</button>
<script src="//d3js.org/d3.v3.min.js"></script>
<script src="profile.js"></script>
<script src="//eligrey.com/demos/FileSaver.js/Blob.js"></script>
<script src="//eligrey.com/demos/FileSaver.js/FileSaver.js"></script>

profile.js

var margin = {top: 20, right: 20, bottom: 30, left: 50},
    width = 500 - margin.left - margin.right,
    height = 300 - margin.top - margin.bottom;

var x = d3.scale.linear()
    .range([0, width]);

var y = d3.scale.linear()
    .range([height, 0]);

var xAxis = d3.svg.axis()
    .scale(x)
    .orient("bottom");

var yAxis = d3.svg.axis()
    .scale(y)
    .orient("left");

var area = d3.svg.area()
    .x(function(d) { return x(d.dist); })
    .y0(height)
    .y1(function(d) { return y(d.alts.DTM25); });

var svg = d3.select("#chart").append("svg")
    .attr("width", width + margin.left + margin.right)
    .attr("height", height + margin.top + margin.bottom)
  .append("g")
    .attr("transform", "translate(" + margin.left + "," + margin.top + ")");

svg.
    style("font-family", "Georgia").
    style("font-size", "15px").
    style("font-style", "normal").
    style("font-variant", "normal").
    style("font-weight", "normal").
    style("text-rendering", "optimizeLegibility").
    style("shape-rendering", "default");

d3.json('profile.json', function(data) {
  x.domain(d3.extent(data, function(d) { return d.dist; }));
  y.domain([0, d3.max(data, function(d) { return d.alts.DTM25; })]);

  svg.append("path")
      .datum(data)
      .attr("class", "area")
      .style('fill', 'steelblue')
      .attr("d", area);

  svg.append("g")
      .attr("class", "x axis")
      .attr("transform", "translate(0," + height + ")")
      .call(xAxis);

  svg.append("g")
      .attr("class", "y axis")
      .call(yAxis)
    .append("text")
      .attr("transform", "rotate(-90)")
      .attr("y", 6)
      .attr("dy", ".71em")
      .style("text-anchor", "end")
      .text("Elevation");
});

d3.select("#generate")
    .on("click", writeDownloadLink);

function writeDownloadLink(){
    try {
        var isFileSaverSupported = !!new Blob();
    } catch (e) {
        alert("blob not supported");
    }

    var html = d3.select("svg")
        .attr("title", "test2")
        .attr("version", 1.1)
        .attr("xmlns", "http://www.w3.org/2000/svg")
        .node().parentNode.innerHTML;

    var blob = new Blob([html], {type: "image/svg+xml"});
    saveAs(blob, "myProfile.svg");
};