nixpkgs/nixos/modules/virtualisation/podman.nix
2021-10-04 12:47:20 +02:00

185 lines
5.4 KiB
Nix

{ config, lib, pkgs, ... }:
let
cfg = config.virtualisation.podman;
toml = pkgs.formats.toml { };
json = pkgs.formats.json { };
inherit (lib) mkOption types;
podmanPackage = (pkgs.podman.override { inherit (cfg) extraPackages; });
# Provides a fake "docker" binary mapping to podman
dockerCompat = pkgs.runCommand "${podmanPackage.pname}-docker-compat-${podmanPackage.version}" {
outputs = [ "out" "man" ];
inherit (podmanPackage) meta;
} ''
mkdir -p $out/bin
ln -s ${podmanPackage}/bin/podman $out/bin/docker
mkdir -p $man/share/man/man1
for f in ${podmanPackage.man}/share/man/man1/*; do
basename=$(basename $f | sed s/podman/docker/g)
ln -s $f $man/share/man/man1/$basename
done
'';
net-conflist = pkgs.runCommand "87-podman-bridge.conflist" {
nativeBuildInputs = [ pkgs.jq ];
extraPlugins = builtins.toJSON cfg.defaultNetwork.extraPlugins;
jqScript = ''
. + { "plugins": (.plugins + $extraPlugins) }
'';
} ''
jq <${cfg.package}/etc/cni/net.d/87-podman-bridge.conflist \
--argjson extraPlugins "$extraPlugins" \
"$jqScript" \
>$out
'';
in
{
imports = [
./podman-dnsname.nix
./podman-network-socket.nix
(lib.mkRenamedOptionModule [ "virtualisation" "podman" "libpod" ] [ "virtualisation" "containers" "containersConf" ])
];
meta = {
maintainers = lib.teams.podman.members;
};
options.virtualisation.podman = {
enable =
mkOption {
type = types.bool;
default = false;
description = ''
This option enables Podman, a daemonless container engine for
developing, managing, and running OCI Containers on your Linux System.
It is a drop-in replacement for the <command>docker</command> command.
'';
};
dockerSocket.enable = mkOption {
type = types.bool;
default = false;
description = ''
Make the Podman socket available in place of the Docker socket, so
Docker tools can find the Podman socket.
Podman implements the Docker API.
Users must be in the <code>podman</code> group in order to connect. As
with Docker, members of this group can gain root access.
'';
};
dockerCompat = mkOption {
type = types.bool;
default = false;
description = ''
Create an alias mapping <command>docker</command> to <command>podman</command>.
'';
};
enableNvidia = mkOption {
type = types.bool;
default = false;
description = ''
Enable use of NVidia GPUs from within podman containers.
'';
};
extraPackages = mkOption {
type = with types; listOf package;
default = [ ];
example = lib.literalExpression ''
[
pkgs.gvisor
]
'';
description = ''
Extra packages to be installed in the Podman wrapper.
'';
};
package = lib.mkOption {
type = types.package;
default = podmanPackage;
internal = true;
description = ''
The final Podman package (including extra packages).
'';
};
defaultNetwork.extraPlugins = lib.mkOption {
type = types.listOf json.type;
default = [];
description = ''
Extra CNI plugin configurations to add to podman's default network.
'';
};
};
config = lib.mkIf cfg.enable (lib.mkMerge [
{
environment.systemPackages = [ cfg.package ]
++ lib.optional cfg.dockerCompat dockerCompat;
environment.etc."cni/net.d/87-podman-bridge.conflist".source = net-conflist;
virtualisation.containers = {
enable = true; # Enable common /etc/containers configuration
containersConf.settings = lib.optionalAttrs cfg.enableNvidia {
engine = {
conmon_env_vars = [ "PATH=${lib.makeBinPath [ pkgs.nvidia-podman ]}" ];
runtimes.nvidia = [ "${pkgs.nvidia-podman}/bin/nvidia-container-runtime" ];
};
};
};
systemd.packages = [ cfg.package ];
systemd.services.podman.serviceConfig = {
ExecStart = [ "" "${cfg.package}/bin/podman $LOGGING system service" ];
};
systemd.sockets.podman.wantedBy = [ "sockets.target" ];
systemd.sockets.podman.socketConfig.SocketGroup = "podman";
systemd.tmpfiles.packages = [
# The /run/podman rule interferes with our podman group, so we remove
# it and let the systemd socket logic take care of it.
(pkgs.runCommand "podman-tmpfiles-nixos" { package = cfg.package; } ''
mkdir -p $out/lib/tmpfiles.d/
grep -v 'D! /run/podman 0700 root root' \
<$package/lib/tmpfiles.d/podman.conf \
>$out/lib/tmpfiles.d/podman.conf
'') ];
systemd.tmpfiles.rules =
lib.optionals cfg.dockerSocket.enable [
"L! /run/docker.sock - - - - /run/podman/podman.sock"
];
users.groups.podman = {};
assertions = [
{
assertion = cfg.dockerCompat -> !config.virtualisation.docker.enable;
message = "Option dockerCompat conflicts with docker";
}
{
assertion = cfg.dockerSocket.enable -> !config.virtualisation.docker.enable;
message = ''
The options virtualisation.podman.dockerSocket.enable and virtualisation.docker.enable conflict, because only one can serve the socket.
'';
}
];
}
]);
}