Amphtml: Validator: Allowing Forms and Inputs

[mkhatib]

AMP will start supporting forms - see #3343, filing this to get discussion going and to start on the validator part in parallel.

• Allow usage of form, input, textarea, select, option tags in AMP Docs.
• Must include amp-form extension script if document uses form/input/select/textarea tags.
• Must use inputs tags inside form tag.
• Form must have at least one <input type=submit>
• Form must have action=”absolute non-cdn https url”
• Form must have target=”_top|_blank”
• <input type=”file|password|image|button”> are invalid
  
  
  
  • This might be revised later on.
  
  
• Other than normal form attributes, allowed attributes include:
  
  
  
  • action-xhr - Optional - to enable a submission flow through XHR. Also has same validation as action attr (absolute, non-cdn link and https) except not required.
  
  

cc/ @powdercloud @Gregable @rudygalfi

[dvoytenko]

This would be good to discuss if we can do this behind the experiment in validator.

[mkhatib]

@powdercloud when can we get this into the validator?

[mkhatib]

@powdercloud any update on when can we get the validation stuff in for forms?

[Gregable]

How important is the "at least one <input type=submit> child" constraint. We noticed that forms could be submitted even without a submit button, such as a text input field and pressing <enter>.

[mkhatib]

Not very important. This was mainly trying to make sure publishers include a submit button (specially on mobile). We can do with runtime error or warning for now.

[honeybadgerdontcare]

Are all other* input attributes optional?

What about textarea, select and option?

*everything except type=”file|password|image|button”

[honeybadgerdontcare]

I noticed in the amp-form documentation that the example includes fieldset and label. We currently do not allow these. Are we intending to allow them here only as children of form and only if amp-form extension is included?

[honeybadgerdontcare]

Added fieldset and label as required children of form and only if amp-form extension is included.
Added all attributes for input except type="file|password|image|button" and those related to type="image" such as "src" and "usemap". Added all attributes for textarea, select and option. Let me know if we should exclude any others.

[Gregable]

Resolved, but still waiting to deploy to cdn.ampproject.org.

[mkhatib]

Thanks so much!

Added fieldset and label as required children of form

This doesn't mean that publishers have to have label and fieldset inside form? It only means that if they use them in their AMP Doc they must be a descendant of form, right?

[honeybadgerdontcare]

Yes, that's correct. If label or fieldset appear in the doc, then they must be a descendant of form and also include the amp-form extension script.

[Gregable]

This has now been deployed everywhere.

[niutech]

@mkhatib Why are <input type="password"> and <input type="button"> not allowed in AMP? How can I make a login form or add any buttons except for submit/reset? Please reconsider allowing them.