nixpkgs/nixos/modules/virtualisation/docker.nix
2016-08-16 00:19:25 +03:00

122 lines
3.6 KiB
Nix

# Systemd services for docker.
{ config, lib, pkgs, ... }:
with lib;
let
cfg = config.virtualisation.docker;
pro = config.networking.proxy.default;
proxy_env = optionalAttrs (pro != null) { Environment = "\"http_proxy=${pro}\""; };
in
{
###### interface
options.virtualisation.docker = {
enable =
mkOption {
type = types.bool;
default = false;
description =
''
This option enables docker, a daemon that manages
linux containers. Users in the "docker" group can interact with
the daemon (e.g. to start or stop containers) using the
<command>docker</command> command line tool.
'';
};
socketActivation =
mkOption {
type = types.bool;
default = true;
description =
''
This option enables docker with socket activation. I.e. docker will
start when first called by client.
'';
};
storageDriver =
mkOption {
type = types.enum ["aufs" "btrfs" "devicemapper" "overlay" "zfs"];
default = "devicemapper";
description =
''
This option determines which Docker storage driver to use.
'';
};
extraOptions =
mkOption {
type = types.separatedString " ";
default = "";
description =
''
The extra command-line options to pass to
<command>docker</command> daemon.
'';
};
postStart =
mkOption {
type = types.lines;
default = ''
while ! [ -e /var/run/docker.sock ]; do
sleep 0.1
done
'';
description = ''
The postStart phase of the systemd service. You may need to
override this if you are passing in flags to docker which
don't cause the socket file to be created. This option is ignored
if socket activation is used.
'';
};
};
###### implementation
config = mkIf cfg.enable (mkMerge [
{ environment.systemPackages = [ pkgs.docker ];
users.extraGroups.docker.gid = config.ids.gids.docker;
systemd.services.docker = {
description = "Docker Application Container Engine";
wantedBy = optional (!cfg.socketActivation) "multi-user.target";
after = [ "network.target" ] ++ (optional cfg.socketActivation "docker.socket") ;
requires = optional cfg.socketActivation "docker.socket";
serviceConfig = {
ExecStart = "${pkgs.docker}/bin/docker daemon --group=docker --storage-driver=${cfg.storageDriver} ${optionalString cfg.socketActivation "--host=fd://"} ${cfg.extraOptions}";
# I'm not sure if that limits aren't too high, but it's what
# goes in config bundled with docker itself
LimitNOFILE = 1048576;
LimitNPROC = 1048576;
} // proxy_env;
path = [ pkgs.kmod ] ++ (optional (cfg.storageDriver == "zfs") pkgs.zfs);
environment.MODULE_DIR = "/run/current-system/kernel-modules/lib/modules";
postStart = if cfg.socketActivation then "" else cfg.postStart;
# Presumably some containers are running we don't want to interrupt
restartIfChanged = false;
};
}
(mkIf cfg.socketActivation {
systemd.sockets.docker = {
description = "Docker Socket for the API";
wantedBy = [ "sockets.target" ];
socketConfig = {
ListenStream = "/var/run/docker.sock";
SocketMode = "0660";
SocketUser = "root";
SocketGroup = "docker";
};
};
})
]);
}