Sitemap hreflang syntax invalid for regional language variants

[strophy]

The hreflang for regional variations in sitemap.xml follows the format of the URL language slug generated by Sphinx, e.g. zh_CN for Chinese (China). This is invalid syntax for hreflang in a sitemap (reference), where a hyphen must be used instead, e.g. zh-CN. Alternatively, it is also valid to define the script of the language instead, e.g. zh-Hans for Simplified Chinese. Some sort of library to perform this conversion, a lookup table or a user-facing option could help fix this.

Example from: https://docs.dash.org/sitemap.xml

<xhtml:link rel="alternate" hreflang="zh_CN" href="http://docs.dash.org/zh_CN/latest/"/>

[stsewd]

The fact that we rely on sphinx for this make it hard to follow the standard way, there are other parts of the code that we should take care of too.

[saadmk11]

Hey @humitos can you tell me how should this be approached? And what needs to be changed to fix this?

[humitos]

@saadmk11 the hreflang label from the sitemap uses some incorrect codes. Those incorrect ones (for example, zh_CN) should be replaced for the correct ones (zh-CN). The linked document from the description has more detailed information.