Added data-* and aria-* attributes

[rmarren1]

plotly/dash#237

[chriddyp]

Let's add aria-* too

[ngnpope]

Hi @rmarren1,

I've also not been able to use the role attribute with html.A():

TypeError: Unexpected keyword argument `role`

This attribute is required for use with aria-* attributes, so it would be good if it were supported.

[rmarren1]

Are there any elements where role should not be allowed? It is does not appear in https://developer.mozilla.org/en-US/docs/Web/HTML/Attributes which is why it is currently not supported, but it could be hard-coded into the generation script if it applies to all components.

[ngnpope]

Can be applied to any element:

• https://www.w3.org/TR/html5/dom.html#aria-role-attribute

Other documents of interest:

• https://developer.mozilla.org/en-US/docs/Web/Accessibility/ARIA
• https://www.w3.org/TR/role-attribute/
• https://www.w3.org/TR/wai-aria-1.1/
• https://www.w3.org/TR/html-aria/

Hard-coding this seems sensible if that is already being done for aria-* as part of this PR.

For background, I bumped into this because of using Bootstrap which requires data-* for some of the scripted components. Have worked around the issue in the meantime client-side by using a mutation observer and adding the attributes as the elements appear.

[rmarren1]

added role

[ngnpope]

Thanks!

[chriddyp]

@rmarren1 - I'm 👍 with these changes. Is there anything else that you would like to add? Otherwise, I will merge and release.

[rmarren1]

I'm good with it, go ahead!