nixpkgs/lib/build-vms.nix

89 lines
3.2 KiB
Nix

{ system, minimal ? false }:
let pkgs = import <nixpkgs> { config = {}; inherit system; }; in
with pkgs;
with import ../lib/qemu-flags.nix;
rec {
inherit pkgs;
# Build a virtual network from an attribute set `{ machine1 =
# config1; ... machineN = configN; }', where `machineX' is the
# hostname and `configX' is a NixOS system configuration. Each
# machine is given an arbitrary IP address in the virtual network.
buildVirtualNetwork =
nodes: let nodesOut = lib.mapAttrs (n: buildVM nodesOut) (assignIPAddresses nodes); in nodesOut;
buildVM =
nodes: configurations:
import ./eval-config.nix {
inherit system;
modules = configurations ++
[ ../modules/virtualisation/qemu-vm.nix
../modules/testing/test-instrumentation.nix # !!! should only get added for automated test runs
{ key = "no-manual"; services.nixosManual.enable = false; }
] ++ lib.optional minimal ../modules/testing/minimal-kernel.nix;
extraArgs = { inherit nodes; };
};
# Given an attribute set { machine1 = config1; ... machineN =
# configN; }, sequentially assign IP addresses in the 192.168.1.0/24
# range to each machine, and set the hostname to the attribute name.
assignIPAddresses = nodes:
let
machines = lib.attrNames nodes;
machinesNumbered = lib.zipTwoLists machines (lib.range 1 254);
nodes_ = lib.flip map machinesNumbered (m: lib.nameValuePair m.first
[ ( { config, pkgs, nodes, ... }:
let
interfacesNumbered = lib.zipTwoLists config.virtualisation.vlans (lib.range 1 255);
interfaces =
lib.flip map interfacesNumbered ({ first, second }:
{ name = "eth${toString second}";
ipAddress = "192.168.${toString first}.${toString m.second}";
subnetMask = "255.255.255.0";
}
);
in
{ key = "ip-address";
config =
{ networking.hostName = m.first;
networking.interfaces = interfaces;
networking.primaryIPAddress =
lib.optionalString (interfaces != []) (lib.head interfaces).ipAddress;
# Put the IP addresses of all VMs in this machine's
# /etc/hosts file. If a machine has multiple
# interfaces, use the IP address corresponding to
# the first interface (i.e. the first network in its
# virtualisation.vlans option).
networking.extraHosts = lib.flip lib.concatMapStrings machines
(m: let config = (lib.getAttr m nodes).config; in
lib.optionalString (config.networking.primaryIPAddress != "")
("${config.networking.primaryIPAddress} " +
"${config.networking.hostName}\n"));
virtualisation.qemu.options =
lib.flip map interfacesNumbered
({ first, second }: qemuNICFlags second first m.second);
};
}
)
(lib.getAttr m.first nodes)
] );
in lib.listToAttrs nodes_;
}