The locale is completely dependent on the user, as much as its email or
CSRF token, so it does not make much sense to have it in a separate
variable: for different users we might have to use different locales.
Also, this means one less variable to pass to handlers, that most of
them will need the user at some point or another (i.e., to render its
profile icon).
The thing is that i can not import `app.User` from the template package
because it would create an import cycle. I created the `auth` package
just because of that.
I thought that the login code would be better moved to the auth package
as well, but of course then i would reintroduce the import cycle between
auth and template.
To get the user from the database i have to set the cookie first, that
was already done in database.MustAcquire, but i thought they were too
far apart, even thought they are so related. So, the cookie, and thus
the role, is set when getting the user, that is actually the first thing
to do once the connection is acquired. However, that way the database
package has no knowledge of cookies, and the code that sets the cookie
and retrieves the user are next to each other.
I applied the same logic to the changes of locale.Match: it has not
business knowing that the accept language string comes from a request;
it only needs the actual string. Also, the TODO comment about getting
the user’s locale made no sense, now, because app already knows that
locale, so there is no need to pass the user to the locale package.
Getting the locale is done after retrieving the user from the database,
for the same reason the connection is Acquired as far up as possible:
almost every request will need this value, together with the user and
the database connection.
I am a bit affraid that i will end up with functions that always expect
these three values. Maybe i can put the locale inside user, as it is
the user’s locale, after all, no matter if it came from the database or
the user agent, but connection and user must be separate, i think.
We’ll see.
Almost all request will need the database connection, either because
they will perform queries or because they need to check if the user is
logged in, for instance, so it should be acquired as far above as
possible to avoid acquiring multiple connections.
This is specially true since i have to pass the cookie to the database
to switch role and set request.user.email and request.user.cookie
config variables. I do not want to do that many times per request.
It is a lot of code having to check the login variables inside the POST
handler, and i could not mark each input field individually as invalid
because the generic errors array i was using did no identify which field
had the error.
Thus, i use more or less the same technique as with Numerus: a struct
with the value and the error message. This time the input field does
not have the label and extra attributes because i believe this belongs
to the template: if i want do reuse the same form template, i should
create a common template rather than defining everything in Go.
The name is a bit different, however, because it has meaning both to the
front and back ends, as it needs to be exactly the same. Writing it
twice is error-prone, as with a rename i could easily forget to change
one or the other, and here i see value in having that in Go, because
it is also used in code.
jordi fita mas