d3-fetch

d3-fetch

This module provides convenient parsing on top of Fetch. For example, to load a text file:

const text = await d3.text("/path/to/file.txt");
console.log(text); // Hello, world!

To load and parse a CSV file:

const data = await d3.csv("/path/to/file.csv");
console.log(data); // [{"Hello": "world"}, …]

This module has built-in support for parsing JSON, CSV, and TSV. You can parse additional formats by using text directly. (This module replaced d3-request.)

Installing

If you use npm, npm install d3-fetch. You can also download the latest release on GitHub. For vanilla HTML in modern browsers, import d3-fetch from Skypack:

<script type="module">

import {csv} from "https://cdn.skypack.dev/d3-fetch@3";

csv("/path/to/file.csv").then((data) => {
  console.log(data); // [{"Hello": "world"}, …]
});

</script>

For legacy environments, you can load d3-fetch’s UMD bundle from an npm-based CDN such as jsDelivr; a d3 global is exported:

<script src="https://cdn.jsdelivr.net/npm/d3-fetch@3"></script>
<script>

d3.csv("/path/to/file.csv").then((data) => {
  console.log(data); // [{"Hello": "world"}, …]
});

</script>

API Reference

# d3.blob(input[, init]) · Source

Fetches the binary file at the specified input URL as a Blob. If init is specified, it is passed along to the underlying call to fetch; see RequestInit for allowed fields.

# d3.buffer(input[, init]) · Source

Fetches the binary file at the specified input URL as an ArrayBuffer. If init is specified, it is passed along to the underlying call to fetch; see RequestInit for allowed fields.

# d3.csv(input[, init][, row]) · Source

Equivalent to d3.dsv with the comma character as the delimiter.

# d3.dsv(delimiter, input[, init][, row]) · Source

Fetches the DSV file at the specified input URL. If init is specified, it is passed along to the underlying call to fetch; see RequestInit for allowed fields. An optional row conversion function may be specified to map and filter row objects to a more-specific representation; see dsv.parse for details. For example:

const data = await d3.dsv(",", "test.csv", (d) => {
  return {
    year: new Date(+d.Year, 0, 1), // convert "Year" column to Date
    make: d.Make,
    model: d.Model,
    length: +d.Length // convert "Length" column to number
  };
});

If only one of init and row is specified, it is interpreted as the row conversion function if it is a function, and otherwise an init object.

See also d3.csv and d3.tsv.

# d3.html(input[, init]) · Source

Fetches the file at the specified input URL as text and then parses it as HTML. If init is specified, it is passed along to the underlying call to fetch; see RequestInit for allowed fields.

# d3.image(input[, init]) · Source

Fetches the image at the specified input URL. If init is specified, sets any additional properties on the image before loading. For example, to enable an anonymous cross-origin request:

const img = await d3.image("https://example.com/test.png", {crossOrigin: "anonymous"});

# d3.json(input[, init]) · Source

Fetches the JSON file at the specified input URL. If init is specified, it is passed along to the underlying call to fetch; see RequestInit for allowed fields. If the server returns a status code of 204 No Content or 205 Reset Content, the promise resolves to undefined.

# d3.svg(input[, init]) · Source

Fetches the file at the specified input URL as text and then parses it as SVG. If init is specified, it is passed along to the underlying call to fetch; see RequestInit for allowed fields.

# d3.text(input[, init]) · Source

Fetches the text file at the specified input URL. If init is specified, it is passed along to the underlying call to fetch; see RequestInit for allowed fields.

# d3.tsv(input[, init][, row]) · Source

Equivalent to d3.dsv with the tab character as the delimiter.

# d3.xml(input[, init]) · Source

Fetches the file at the specified input URL as text and then parses it as XML. If init is specified, it is passed along to the underlying call to fetch; see RequestInit for allowed fields.