html/template: "application/ld+json" MIME type is not understood as JS

[eklitzke]

The text/html package does not understand the "application/ld+json" MIME type to be JS. This is a standard format endorsed by the W3C and various search engines. Search engines like Google require this data to be inline in a page's HTML using a tag like <script type="application/ld+json">JSON DATA HERE</script>, so it is important for the text/html template engine to be aware of how to escape JSON-LD data, as the data cannot be placed in an external script file. For more information on JSON-LD see [1] and [2].

I plan to submit a trivial PR to add json+ld support to text/html, but I am creating a GitHub issue first to describe the issue as per the contribution policy.

[1] https://en.wikipedia.org/wiki/JSON-LD
[2] https://developers.google.com/search/docs/guides/intro-structured-data

[gopherbot]

Change https://golang.org/cl/120835 mentions this issue: text/html: MIME type "application/ld+json: should be escaped as JS

[bradfitz]

/cc @mikesamuel @FiloSottile

[FiloSottile]

A JSON-LD document must be a valid JSON document as described in [RFC4627].

For the purposes of text/html, this is indeed JSON. LGTM.