quickchart-php

A PHP client for the quickchart.io chart image API.

Installation

Use the QuickChart.php library in this project, or install from packagist.

composer require ianw/quickchart

Usage

This library provides a QuickChart class. Import and instantiate it. Then set properties on it and specify a Chart.js config:

$chart = new QuickChart(array(
  'width' => 500,
  'height' => 300
));

$chart->setConfig('{
  type: "bar",
  data: {
    labels: ["Hello world", "Test"],
    datasets: [{
      label: "Foo",
      data: [1, 2]
    }]
  }
}');

Use getUrl() on your QuickChart object to get the encoded URL that renders your chart:

echo $chart->getUrl();
// https://quickchart.io/chart?c=%7B%22type%22%3A%22bar%22%2C%22data%22%3A%7B%22labels%22%3A%5B%22Hello+world%22%2C%22Test%22%5D%2C%22datasets%22%3A%5B%7B%22label%22%3A%22Foo%22%2C%22data%22%3A%5B1%2C2%5D%7D%5D%7D%7D&w=500&h=300

If you have a long or complicated chart, use getShortUrl() to get a fixed-length URL using the quickchart.io web service (note that these URLs only persist for a short time unless you have a subscription):

echo $chart->getShortUrl();
// https://quickchart.io/chart/render/f-a1d3e804-dfea-442c-88b0-9801b9808401

The URLs will render an image of a chart:

Creating the chart object

The QuickChart class constructor accepts an array containing the following keys. All are optional and can be set after object creation:

config: array or string

The actual Chart.js chart configuration.

width: int

Width of the chart image in pixels. Defaults to 500

height: int

Height of the chart image in pixels. Defaults to 300

format: string

Format of the chart. Defaults to png.

backgroundColor: string

The background color of the chart. Any valid HTML color works. Defaults to #ffffff (white). Also takes rgb, rgba, and hsl values.

devicePixelRatio: float

The device pixel ratio of the chart. This will multiply the number of pixels by the value. This is usually used for retina displays. Defaults to 1.0.

Setting properties

Getting URLs

There are two ways to get a URL for your chart object.

getUrl: string

Returns a URL that will display the chart image when loaded.

getShortUrl: string

Uses the quickchart.io web service to create a fixed-length chart URL that displays the chart image. Returns a URL such as https://quickchart.io/chart/render/f-a1d3e804-dfea-442c-88b0-9801b9808401.

Note that short URLs expire after a few days for users of the free service. You can subscribe to keep them around longer.

Other outputs

toBinary: binary string

Returns a binary string representing the chart image

toFile($path: string)

Write the image to a file

For example:

$chart->toFile('/tmp/myfile.png')

More examples

Checkout the examples directory to see other usage.