When starting a blog: AttributeError: 'NoneType' object has no attribute '_set_canonical_url'

[janban-outlook]

As soon as I add my first page in a blog, I get this error when running mkdocs serve.

Traceback (most recent call last):
  File "/home/jan/.local/bin/mkdocs", line 8, in <module>
    sys.exit(cli())
  File "/home/jan/.local/lib/python3.10/site-packages/click/core.py", line 1134, in __call__
    return self.main(*args, **kwargs)
  File "/home/jan/.local/lib/python3.10/site-packages/click/core.py", line 1059, in main
    rv = self.invoke(ctx)
  File "/home/jan/.local/lib/python3.10/site-packages/click/core.py", line 1665, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "/home/jan/.local/lib/python3.10/site-packages/click/core.py", line 1401, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/home/jan/.local/lib/python3.10/site-packages/click/core.py", line 767, in invoke
    return __callback(*args, **kwargs)
  File "/home/jan/.local/lib/python3.10/site-packages/mkdocs/__main__.py", line 270, in serve_command
    serve.serve(**kwargs)
  File "/home/jan/.local/lib/python3.10/site-packages/mkdocs/commands/serve.py", line 86, in serve
    builder(config)
  File "/home/jan/.local/lib/python3.10/site-packages/mkdocs/commands/serve.py", line 67, in builder
    build(config, live_server=None if is_clean else server, dirty=is_dirty)
  File "/home/jan/.local/lib/python3.10/site-packages/mkdocs/commands/build.py", line 311, in build
    nav = config.plugins.on_nav(nav, config=config, files=files)
  File "/home/jan/.local/lib/python3.10/site-packages/mkdocs/plugins.py", line 536, in on_nav
    return self.run_event('nav', nav, config=config, files=files)
  File "/home/jan/.local/lib/python3.10/site-packages/mkdocs/plugins.py", line 507, in run_event
    result = method(item, **kwargs)
  File "/home/jan/.local/lib/python3.10/site-packages/mkdocs_static_i18n/plugin.py", line 76, in on_nav
    nav = self.reconfigure_material_blog(nav, config, files)
  File "/home/jan/.local/lib/python3.10/site-packages/mkdocs_static_i18n/reconfigure.py", line 765, in reconfigure_material_blog
    file.page._set_canonical_url(mkdocs_config.get('site_url', None))
AttributeError: 'NoneType' object has no attribute '_set_canonical_url'

The hello.md page is just the simple sample page from the documentation.

The relevant section in mkdocs.yml is:

nav:
  - Home: index.md
  - contact.md
  - Blog:
    - blog/index.md
    

The file structure is:

 
 mkdocs.yml
 docs
   index.md
     posts
        hello.md

As soon as I delete the hello.md file, mkdocs serve runs fine again

[alexvoss]

This seems to be a variation of #4863 in that it seems to involve an interaction between the i18n plugin and the blog plugin.

[janban-outlook]

Indeed. I use i18n for the other pages.

I'll try the approach that is suggested there. (#2346)

[squidfunk]

Note that this is one of the reasons why we started work on the projects plugin – maybe something to consider. We'd be happy to learn about requirements for multi-language support and are happy to add anything that is necessary to make it work smoothly to the projects plugin 🚀 Also see #5800.

[janban-outlook]

Yes, I read about it this morning. Sounds like it is a good approach for me.
I currently have a multi language website with a blog using a Hugo theme. But I really like mkdocs-material :)