nixos/cockroachdb: simplify dataDir management, tweaks #51535
Conversation
This cleans up the CockroachDB expression, with a few suggestions from @aszlig. However, it brought up the note of using systemd's StateDirectory= directive, which is a nice feature for managing long-term data files, especially for UID/GID assigned services. However, it can only manage directories under /var/lib (for global services), so it has to introduce a special path to make use of it at all in the case someone wants a path at a different root. While the dataDir directive at the NixOS level is _occasionally_ useful, I've gone ahead and removed it for now, as this expression is so new, and it makes the expression cleaner, while other kinks can be worked out and people can test drive it. CockroachDB's dataDir directive, instead, has been replaced with systemd's StateDirectory management to place the data under /var/lib/cockroachdb for all uses. There's an included RequiresMountsFor= clause like usual though, so if people want dependencies for any kind of mounted device at boot time/before database startup, it's easy to specify using their own mount/filesystems clause. This can also be reverted if necessary, but, we can see if anyone ever actually wants that later on before doing it -- it's a backwards compatible change, anyway. Signed-off-by: Austin Seipp <aseipp@pobox.com>
GrahamcOfBorg
added
6.topic: nixos
| chown -R ${cfg.user} ${cfg.dataDir} | ||
| fi | ||
| ''; | ||
| unitConfig.RequiresMountsFor = "/var/lib/cockroachdb"; |
There was a problem hiding this comment.
From systemd.exec(5):
Units with WorkingDirectory=, RootDirectory=, RootImage=, RuntimeDirectory=, StateDirectory=, CacheDirectory=, LogsDirectory= or ConfigurationDirectory= set automatically gain dependencies of type Requires= and After= on all mount units required to access the specified paths. This is equivalent to having them listed explicitly in RequiresMountsFor=.
| "0.25" both represent 25% of the available system memory. The values | ||
| "1000000000" and "1GB" both represent 1 gigabyte of memory. | ||
| decimal-point number, or any bytes-based unit. For example, | ||
| <literal>"25%"</literal>, <literal>"0.25"</literal> both represent |
There was a problem hiding this comment.
Hm, maybe remove the double quotes as well, as <literal/> are already formatted in a different way in the manual.
There was a problem hiding this comment.
Do they actually put quotes, though? I should have double checked, I just left them to make it a bit more clear they're of string type.
| country=us,region=us-west,datacenter=us-west-1b,rack=12 | ||
| country=ca,region=ca-east,datacenter=ca-east-2,rack=4 | ||
|
|
||
| planet=earth,province=manitoba,colo=secondary,power=3 | ||
| </literal> |
There was a problem hiding this comment.
Wouldn't that be one single line? Like eg. if used for the example attribute of mkOption:
mkOption {
type = types.nullOr types.str;
default = null;
example = "country=us,region=us-west,datacenter=us-west-1b,rack=12,"
+ "country=ca,region=ca-east,datacenter=ca-east-2,rack=4,"
+ "planet=earth,province=manitoba,colo=secondary,power=3";
description = ''
...
'';
}There was a problem hiding this comment.
Ah, maybe. I'll double check this too. <example> doesn't seem to work though (some kind of nested <para> conflict, I think?) but I'll look around for this, too.
There was a problem hiding this comment.
<example/> works within <para/>, but you'll need a <title/> or <info/> child. <informalexample/> might be better suited here. Or as said: It's maybe even better to use the example attribute of mkOption.
|
@thoughtpolice Can you wait until people have reviewed your PRs before merging them? |
This cleans up the CockroachDB expression, with a few suggestions from
@aszlig.
However, it brought up the note of using systemd's StateDirectory=
directive, which is a nice feature for managing long-term data files,
especially for UID/GID assigned services. However, it can only manage
directories under /var/lib (for global services), so it has to introduce
a special path to make use of it at all in the case someone wants a path
at a different root.
While the dataDir directive at the NixOS level is occasionally useful,
I've gone ahead and removed it for now, as this expression is so new,
and it makes the expression cleaner, while other kinks can be worked out
and people can test drive it.
CockroachDB's dataDir directive, instead, has been replaced with
systemd's StateDirectory management to place the data under
/var/lib/cockroachdb for all uses.
There's an included RequiresMountsFor= clause like usual though, so if
people want dependencies for any kind of mounted device at boot
time/before database startup, it's easy to specify using their own
mount/filesystems clause.
This can also be reverted if necessary, but, we can see if anyone ever
actually wants that later on before doing it -- it's a backwards
compatible change, anyway.
Signed-off-by: Austin Seipp aseipp@pobox.com
Motivation for this change
Things done
sandboxinnix.confon non-NixOS)nix-shell -p nox --run "nox-review wip"./result/bin/)nix path-info -Sbefore and after)