(gnu home services xdg): Wrong value for $XDG_STATE

Philip McGrath wrote on 26 Feb 2023 12:43

Recipients:(name . bug-guix)(address . bug-guix@gnu.org)

Message-ID:21836149.EfDdHjke4D@bastet

Hi,

The following part of the definition of

`home-xdg-base-directories-configuration` in `(gnu home services xdg)` is

wrong:

```

(state-home

(path "$HOME/.local/var/lib")

"Base directory for programs to store state files, like databases,

analogus to @file{/var/lib}, but for user. It is not a part of XDG

Base Directory Specification, but helps to make implementation of home

services more consistent.")

```

First of all, version 0.8 of the XDG Base Directory Specification added a

specification of $XDG_STATE_HOME in May 2021:

Unfortunately, "$HOME/.local/var/lib" is not the specified default value: the

specification says it should be "$HOME/.local/state".

Can we just fix the default value, or do we need a more involved compatibility

plan? Maybe we should mention it in the channel news? Since the spec says it

should contain data "that is not important or portable enough to the user that

it should be stored in $XDG_DATA_HOME", maybe just changing it would be ok.

Moreover, it seems like the actually non-standard variable $XDG_LOG_HOME:

```

(log-home

(path "$HOME/.local/var/log")

"Base directory for programs to store log files, analogus to

@file{/var/log}, but for user. It is not a part of XDG Base Directory

Specification, but helps to make implementation of home services more

consistent.")

```

overlaps with the purposes of $XDG_STATE_HOME, which the spec says:

Toggle quote (7 lines)

> may contain:

> - actions history (logs, history, recently used files, …)

> - current state of the application that can be reused on a restart (view,

> layout, open files, undo history, …)

Do we really need $XDG_LOG_HOME? It looks like it's currently used only to

control the locations of "dbus.log", "batsignal.log", "shepherd.log", and

"mcron.log". Could they just go in $XDG_STATE_HOME?

If there is some compelling need, I think the variable name should not begin

with XDG.

-Philip

(gnu home services xdg): Wrong value for $XDG_STATE_HOME