nixos: define defaut state dir (/var...) prefix

[offlinehacker]

We need an option to define a default state dir prefix, something like system.defaultStateDir = "/var";. other nixos modules can then use it like dataDir = ${config.system.defaultStateDir}/db/postgresql;.

I want to know:

• Where should i put this option(in which nixos file, under which namespace)?
• Do you see any problems with this behaviour?

This is also related to #1689

[vcunat]

Note: many packages need to know the state dir at configure-time (so rebuild is typically needed).

[offlinehacker]

Well yes, they won't work with changed state dir if they won't get rebuilt,
but that's something that has to be fixed upstream.
On Feb 18, 2014 5:21 PM, "Vladimír Čunát" [email protected] wrote:

Note: many packages need to know the state dir at configure-time (so
rebuild is typically needed).

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[edolstra]

What's the use case for this? I mean, I can see why you want to override the state directory for a specific service (like PostgreSQL), but there already are options for that.

[offlinehacker]

Well yes, but then you can globally override and don't have to override for
each service. This is really helpfull in a case of user services where you
have to set to someting like user's home.

On Tue, Feb 18, 2014 at 5:26 PM, Eelco Dolstra [email protected]:

What's the use case for this? I mean, I can see why you want to override
the state directory for a specific service (like PostgreSQL), but there
already are options for that.

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[offlinehacker]

It's just one flag that could not hurt anyone and is used only for services. I tought services.dataPrefix by default set to /var. I'm just wondering if it's okay to rewrite nixos modules to use it?

[shlevy]

I think this will be more useful once we have user services, but no real objections from me (other than the general objection that we shouldn't provide configurability that doesn't provide useful benefits)

[offlinehacker]

I already have services.dataDir, which is just a simple string(defaulting
to /var), that modules can use, defined in my fork, and i use it in my user
services implementation. I will make pull request for services.dataDir
if you think it's ok?
On Apr 5, 2014 7:38 PM, "Shea Levy" [email protected] wrote:

I think this will be more useful once we have user services, but no real
objections from me (other than the general objection that we shouldn't
provide configurability that doesn't provide useful benefits)

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[shlevy]

Sure, is your user services implementation available as well?

[offlinehacker]

Here: https://github.com/kiberpipa/nix-rehash/tree/master/nix-servicesBasicly
nix-rehash is a library with a few functions, nix-services being
one of them. I use this primary for distribution of development
environments, setting systemd.dataDir to some temporary location.
On Apr 6, 2014 12:08 AM, "Shea Levy" [email protected] wrote:

Sure, is your user services implementation available as well?

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[offlinehacker]

Will make a pull request with system.dataDir avalible and used in a few
modules.
On Apr 6, 2014 12:54 AM, "Jaka Hudoklin" [email protected] wrote:

Here: https://github.com/kiberpipa/nix-rehash/tree/master/nix-servicesBasicly nix-rehash is a library with a few functions, nix-services being
one of them. I use this primary for distribution of development
environments, setting systemd.dataDir to some temporary location.
On Apr 6, 2014 12:08 AM, "Shea Levy" [email protected] wrote:

Sure, is your user services implementation available as well?

Reply to this email directly or view it on GitHubhttps://github.com//issues/1773#issuecomment-39652212
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[domenkozar]

Closing since it's little value and PR can be opened any time