Isomorphic build support

[benmccann]

Chart.js does not work with Vite / SvelteKit out of the box. This is because Chart.js provides a build via the main field in package.json which provides just a default export. Meanwhile it provides a build in module which provides named exports. Vite tries to use the module build on the client and the main build on the server which causes the build to fail because you can't write code that is compatible with both these packages. To work around this, you can specify the option vite.ssr.noExternal: ['chart.js'], but this is hard for users to figure out and it'd be much nicer to provide builds that are the same shapte

There are a couple things we could do:

• We should put a build in main that uses the same entry file as our ESM build and add "type": "module" to package.json. This is probably the best option
• We could remove main. Chart.js isn't really that useful on the server-side, so we could just stop telling Vite that we have a server-side build. It would still try to build it on the server, but would fallback to the ESM implementation

[simonbrunel]

An interesting thread about moving to pure ESM package.

Chart.js isn't really that useful on the server-side...

I don't fully agree, even if it's clearly not the main usage, Chart.js is used server side (though I don't know how it's imported). So whatever solution is adopted, we should make sure to still support server-side use cases in pure node environment.

[etimberg]

I recall a few threads of folks doing server side rendering using node-canvas to generate images for reports

[dangreen]

@benmccann Does #10525 solve this issue?

[benmccann]

Yes! Thanks

[rpf3]

@dangreen any idea when it will be released?

[dangreen]

@rpf3 it will be released in v4. You can follow the progress here

https://github.com/chartjs/Chart.js/milestone/23