State of Chart.js & V3.0

3.0 final is available

We’re proud to announce that Chart.js 3.0.0 is now available. Get it with npm install --save chart.js

• Release notes
• npm
• Migration guide
• Docs
• API
• Samples

Overview

Chart.js 3.0 introduces a number of breaking changes. Chart.js 2.0 was released in April 2016. In the years since then, as Chart.js has grown in popularity and feature set, we’ve learned some lessons about how to better create a charting library. In order to improve performance, offer new features, and improve maintainability, it was necessary to break backwards compatibility, but we aimed to do so only when worth the benefit. Some major highlights of v3 include:

• Large performance improvements including the ability to skip data parsing and render charts in parallel via webworkers
• Additional configurability and scriptable options with better defaults
• Completely rewritten animation system
• Rewritten filler plugin with numerous bug fixes
• Documentation migrated from GitBook to Docusaurus
• API Documentation generated and verified by TypeScript
• No more CSS injection
• Tons of bug fixes
• Tree shaking

In this issue we’ll maintain a list of committed, nice-to-have, and proposed features for v3. Feedback from the community will help shape the prioritization for v3.

Committed Features

• Rollup configured for ES6+ babel translation (#6555)
• Remove custom (https://github.com/chartjs/Chart.js/pull/6605)
• Remove all deprecated code
  • Most deprecated code has been removed. However grep -ri backward src still returns a handful of results. Also need to search the code for TODOs
• Prefix all private methods with underscore
• Make ticks objects (https://github.com/chartjs/Chart.js/issues/5019) (or not? should we revert? see https://github.com/chartjs/Chart.js/pull/6791)
• Remove moment from package.json (https://github.com/chartjs/Chart.js/pull/6745), move the moment adapter to an external project, and remove the rollup optional plugin
• Remove zeroLineIndex feature and replace with function based axis properties (https://github.com/chartjs/Chart.js/pull/6697 & https://github.com/chartjs/Chart.js/pull/6700)
• Change require to import, adopt ES6 classes, use const / let, etc.
• Scale cleanup
  • Change axis options from an array to an object keyed by ID (https://github.com/chartjs/Chart.js/pull/6773)
  • Cleanup getPixelForTick (https://github.com/chartjs/Chart.js/issues/6715)
• Performance Improvements
  • Accept data in a format that doesn’t require parsing (https://github.com/chartjs/Chart.js/issues/6696)
  • Improve performance of finding hovered element (https://github.com/chartjs/Chart.js/issues/6716)
  • Split _options out of _model. Creating _model is expensive right now, since it’s done for each data point. However, _options does not need to be recreated for each data point unless scriptable options are being used. Thus by just using _options directly instead of copying it into _model we would be much more performant (https://github.com/chartjs/Chart.js/pull/6845)
  • Reduce number of objects created (e.g. _view and _model) when animation is disabled (e.g. https://github.com/chartjs/Chart.js/pull/6710).
• Make beginAtZero default be true for bar chart (https://github.com/chartjs/Chart.js/issues/5939)
• Cleanup options (https://github.com/chartjs/Chart.js/issues/5233)
  • Remove element options and remove global from options namespace (https://github.com/chartjs/Chart.js/issues/6684 https://github.com/chartjs/Chart.js/pull/6893)
  • Standardize on using degrees for angles (https://github.com/chartjs/Chart.js/pull/6936)
• Migrate docs from GitBook to Docusaurus (https://github.com/chartjs/Chart.js/pull/7295)
• Support tree shaking / individual module imports (https://github.com/chartjs/Chart.js/issues/7371)
• Leverage index / value concepts
  • Remove horizontalBar and make all charts capable of being horizontal (https://github.com/chartjs/Chart.js/pull/7144)

Proposed / Nice to Have Features

• Scale cleanups
  • Improve the scale interface & document how to use it
  • Investigate normalizing options.scales and option.scale keys for all chart types
• Performance Improvements
  • Support drawing charts without creating elements possibly as external chart type (https://github.com/chartjs/Chart.js/pull/6881)
  • When the tooltip and other hover actions are disabled, the chart should not be redrawn when hovering on it. This would make external custom html tooltips massively faster. Along with this, consider making the default tooltip be an external tooltip (https://github.com/chartjs/Chart.js/issues/7195#issuecomment-598996746)
  • Make sure the tooltip listener only applies to the chart area and not the whole canvas (https://github.com/leeoniya/uPlot/pull/277#issuecomment-663021669)
• Cleanup options (https://github.com/chartjs/Chart.js/issues/5233)
  • Remove overrides of _resolveDataElementOptions and _resolveDatasetElementOptions (https://github.com/chartjs/Chart.js/pull/8374)
  • Make _dataElementOptions an array in all controllers (i.e. line and radar). (https://github.com/chartjs/Chart.js/pull/8374)
  • Ensure user-specified options are applied after defaults. Delete _config and have just a single object holding resolved options (https://github.com/chartjs/Chart.js/pull/8374)
  • Make chart.options private and immutable (user should not directly edit, but should pass in new config to merge)
  • Cleanup interactions options (https://github.com/chartjs/Chart.js/issues/7922)
• Leverage index / value concepts
  • Bar / rectangle cleanup (https://github.com/chartjs/Chart.js/issues/6760)
• Make drawing clearer
  • Investigate making drawings sharper
• Consider renaming axis label to axis title to differentiate from the tick labels
• Improve log scale tick generation (https://github.com/chartjs/Chart.js/issues/7332)
• Bar chart
  • Allow specifying pixels between bars (e.g. 1 px space and fill the rest). Right now it can only be a percentage
• Ideas from @simonbrunel: Chart.js 3.pdf

Won’t do

• Can we move hidden elements to plugin? (https://github.com/chartjs/Chart.js/pull/6255)
• Split out the time scale into it’s own package
• Consider removing data from config so that we have datasets, labels, and options as first level properties. We agreed that data.datasets.data is confusing, but every chart would need to be updated if we changed this and all StackOverflow answers would be outdated

How can you help?

• Provide feedback on which issues you would like prioritized for v3
• Test out alpha & beta releases as they become available. The alpha release is quite stable though we have found a few issues. Thanks to the folks that reported them! Here’s a list of known issues
• Volunteer time to help improve the project

[etimberg]

The first release candidate, v3.0.0-rc was released today.

[kurkle]

@boddunan its getting close. I think #8332 is probably the last breaking change. There will most likely be one more beta and one or more release canditates before release.