d3-shapes

<!DOCTYPE html>
<head>
  <meta charset="utf-8">
  <script src="https://d3js.org/d3.v4.min.js"></script>
  <style>
    body { margin:0;position:fixed;top:0;right:0;bottom:0;left:0; }
  </style>
</head>

<body>
  <script>
    // Feel free to change or delete any of the code you see in this editor!
    var data = [
      {date: new Date(2007, 3, 24), value: 9},
      {date: new Date(2007, 3, 25), value: 9},
      {date: new Date(2007, 3, 26), value: 9},
      {date: new Date(2007, 3, 27), value: 9},
      {date: new Date(2007, 3, 30), value: 9},
      {date: new Date(2007, 4, 1), value: 9},
    ]
    var margins = {top: 20, right: 20, bottom: 20, left: 20};
    var height = 300;
    var svg = d3.select("body").append("svg")
      .attr("width", 960)
      .attr("height", 500)
    
    var xExtent = d3.extent(data, d => d.date);
    var yMax = d3.max(data, d => d.value);
    
    var xScale = d3.scaleTime()
    	.domain(xExtent)
    	.range([margins.left, margins.right]);
    var yScale = d3.scaleLinear()
    	.domain([0, yMax])
    	.range([margins.top, height - margins.top -margins.bottom]);
    
    var line = d3.line()
    	.x(d => xScale(d.date))
			.y(d => yScale(d.value))
    
		svg.append('path')
    	.attr('d', line(data))
    	.attr('stroke', 'blue');
    
//     svg.append("text")
//       .text("Edit the code below to change me!")
//       .attr("y", 200)
//       .attr("x", 120)
//       .style("font-size", 36)
//       .style("font-family", "monospace")
		console.log(line(data));
  </script>
</body>

https://d3js.org/d3.v4.min.js