For now, this is almost identical to the campsite types, but this
section is for purely informational pages that have no other relation
to the database than “belongs to the same company”.
Part of #33.
Had to export and move PublicPage struct to template because i can not
import app from campsites/types: app already imports campsite for the
http handler, and it, in turn, imports the types package for its own
http handler; an import loop.
Also had to replace PublicPage.MustRender with a Setup function because
the page passed down to html/template was the PublicPage struct, not
whatever struct embeds it. I was thinking more of Java inheritance here
rather than struct embedding.
Since the locales is a map, and maps in Go do not have order, sometime
the language switcher was shown in a different order.
I sort by language code, which is as arbitrary as sorting by name, but
makes sense to me.
I realized that locales should be company-dependent: we could have two
companies that show pages in a different subset of the application
locales. It is not the case now, because despite being a “multicompany
application”, it is intended for a single customer, but still makes
sense to include it in Company, even if the subset is the same set as
the application’s.
The language switcher needs the same information as languageLinks
needed, namely the list of locales and the current Path, to construct
the URI to all alternate versions. However, in this case i need access
to this data in the template context, to build the list of links.
At first i use request’s context to hold the list of available locales
from application, and it worked, possibly without ill-effects, but i
realized that i was doing it just to avoid a new parameter. Or, more
precise, an _explicit_ parameter; the context was used to skip the
inner functions between app and template.MustRenderPublic, but the
parameter was there all the same.
Finally, i thought that some handler might want to filter the list of
locales to show only the ones that it has a translation of. In that
case, i would need to extract the locales from the context, filter it,
and create a new request with the updated context. That made little
sense, and made me add the explicit locales parameter.
Since now the template has the same data as languageLinks, there is
little point of having the link in the HTTP response headers, and added
the <link> elements to <head>.
I thought that maybe i could avoid these <links> as they give the exact
same data as the language switch, but Google says nothing of using
regular anchors to gather information about localized versions of the
document[0], thus i opted to be conservative. One can reason that the
<head> has more weight for Google, as most sites with user-generated
content, which could contain these anchors, rarely allow users to edit
the <head>.
[0]: https://developers.google.com/search/docs/specialty/international/localized-versions
I need to check that the user is an employee (or admin) in
administration handlers, but i do not want to do it for each handler,
because i am bound to forget it. Thus, i added the /admin sub-path for
these resources.
The public-facing web is the rest of the resources outside /admin, but
for now there is only home, to test whether it works as expected or not.
The public-facing web can not relay on the user’s language settings, as
the guest user has no way to set that. I would be happy to just use the
Accept-Language header for that, but apparently Google does not use that
header[0], and they give four alternatives: a country-specific domain,
a subdomain with a generic top-level domain (gTLD), subdirectories with
a gTLD, or URL parameters (e.g., site.com?loc=de).
Of the four, Google does not recommend URL parameters, and the customer
is already using subdirectories with the current site, therefor that’s
what i have chosen.
Google also tells me that it is a very good idea to have links between
localized version of the same resources, either with <link> elements,
Link HTTP response headers, or a sitemap file[1]; they are all
equivalent in the eyes of Google.
I have choosen the Link response headers way, because for that i can
simply “augment” ResponseHeader to automatically add these headers when
the response status is 2xx, otherwise i would need to pass down the
original URL path until it reaches the template.
Even though Camper is supposed to be a “generic”, multi-company
application, i think i will stick to the easiest route and write the
templates for just the “first” customer.
[0]: https://developers.google.com/search/docs/specialty/international/managing-multi-regional-sites
[1]: https://developers.google.com/search/docs/specialty/international/localized-versions