Validator reports valid script types as invalid

[aaemnnosttv]

Bug Description

When validating a URL, the validator reports that script types are invalid, in contrast to the valid types defined in the docs for AMP HTML.

According to the AMP HTML Specification, <script> tags are allowed with the following type attributes:

• application/ld+json
• application/json
• text/plain

Of these, only application/ld+json is not flagged as invalid by the validator.

Expected Behaviour

All valid script types outlined by the AMP HTML Spec should not be marked invalid and removed by the AMP Validator.

Steps to reproduce

1. Validate any page with a script tag on the page with either type of application/json or text/plain
2. See validation error

Additional context

• WordPress version: 5.3.2
• Plugin version: 1.4.4
• Gutenberg plugin version (if applicable):
• AMP plugin template mode: Standard
• PHP version: 7.2
• OS: MacOS
• Browser: Chrome
• Device: Macbook Pro

---

Do not alter or remove anything below. The following sections will be managed by moderators only.

Acceptance criteria

Implementation brief

QA testing instructions

Demo

Changelog entry

[westonruter]

These script types are allowed only when they are used on the context of other AMP components. You can't add an application/json script anywhere. It had to be inside of an amp-analytics component, for example.

So this is working as expected.

In v1.5 the error message will be improved to explain why it is invalid.

[aaemnnosttv]

Thanks for clarifying @westonruter! I should have tested this with https://validator.amp.dev first, which fails with the same types as well. Am I interpreting the spec incorrectly or do you think this could be clarified better since it doesn't mention that some types are only valid in a particular context?

[westonruter]

What you have screenshotted are the docs, not the formal spec. (The docs could be made more clear here.) To see what the formal spec requires, you should look at the underlying protoascii.

For example, here is a definition for an application/json that is used for amp-ima-video:
https://github.com/ampproject/amphtml/blob/8be63bf7b769f7c903a7d57bf44f8cca19760743/validator/validator-main.protoascii#L5036-L5055

Notice this key line:

mandatory_parent: "AMP-IMA-VIDEO"

You can see that same by looking at https://github.com/ampproject/amp-wp/blob/develop/includes/sanitizers/class-amp-allowed-tags-generated.php

For every instance of application/json you'll see it has an associated tag_spec that has a mandatory_parent.