Wrap text within circle

Question

I'm using d3 to draw a UML diagram and would like to wrap text within the shapes drawn with d3. I've gotten as far as the code below and can't find a solution to make the text 'fit' within my shape (see image below).

var svg =  d3.select('#svg')
    .append('svg')
        .attr('width', 500)
        .attr('height', 200);

var global = svg.append('g');

global.append('circle')
      .attr('cx', 150)
      .attr('cy', 100)
      .attr('r', 50);

global.append('text')
  .attr('x', 150)
  .attr('y', 100)
  .attr('height', 'auto')
  .attr('text-anchor', 'middle')
  .text('Text meant to fit within circle')
  .attr('fill', 'red');

Answer 1

Here is the best I could do.

I want to center and wrap a text inside a circle or rect in SVG. The text should remain centered (horizontal/vertical) whatever the text length.

svg {
    width: 600px;
    height: 200px;
    background-color: yellow;
}
.circle {
    background-color: blue;
    height: 100%;
    border-radius: 100%;
    text-align: center;
    line-height: 200px;
    font-size: 30px;
}
.circle span {
    line-height: normal;
    display:inline-block;
    vertical-align: middle;
    color: white;
    text-shadow: 1px 1px 2px rgba(0, 0, 0, 0.8);
}

<svg>
    <foreignObject width="200" height="200" x="100" y="100" transform="translate(-100,-100)">
        <div class="circle">
            <span>Here is a</span>
        </div>
    </foreignObject>

    <foreignObject width="200" height="200" x="300" y="100" transform="translate(-100,-100)">
        <div class="circle">
            <span>Here is a paragraph</span>
        </div>
    </foreignObject>

    <foreignObject width="200" height="200" x="500" y="100" transform="translate(-100,-100)">
        <div class="circle">
            <span>Here is a paragraph that requires word wrap</span>
        </div>
    </foreignObject>
</svg>

The transform attribute is not mandatory, I'm using a translate(-r, -r) so that the (x,y) of the foreignObject is like the (cx, cy) of the SVG circle, and width, height = 2*r with r the radius.

I did this to use as nodes within a D3 force layout. I leave as an exercise to translate this snippet into javascript D3's style.