No support for NPM package previews

[ergo]

Hello,

When using https://www.webcomponents.org/preview, there are still checks for bower.json presence so packages that are served from npm cannot be previewed.

Resulting error:

Error - 12 Unable to process element Missing bower.json Currently, only Bower is supported. In the latest tagged version of this repository, ensure there is a valid bower.json.

[gkjohnson]

I ran into this today. Is this just for the preview? Are we able to publish without a bower.json file?

[ergo]

@gkjohnson Yes https://www.webcomponents.org/element/polymer-ui-router - I managed to publish an element here from NPM, just struggle with demos working.

[gkjohnson]

Interesting -- I'm seeing this error in the demos:

Uncaught TypeError: Failed to resolve module specifier "@webcomponents/shadycss/entrypoints/apply-shim.js". Relative references must start with either "/", "./", or "../".

Looks like the site doesn't resolve the bare module imports. I suppose a pre-built version of the element might be the best way to show a demo?

[ergo]

@samuelli is this on the roadmap somewhere?