nixpkgs/nixos/modules/services/continuous-integration/buildkite-agents.nix
2020-02-28 15:34:37 +00:00

276 lines
9.1 KiB
Nix

{ config, lib, pkgs, ... }:
with lib;
let
cfg = config.services.buildkite-agents;
mkHookOption = { name, description, example ? null }: {
inherit name;
value = mkOption {
default = null;
inherit description;
type = types.nullOr types.lines;
} // (if example == null then {} else { inherit example; });
};
mkHookOptions = hooks: listToAttrs (map mkHookOption hooks);
hooksDir = cfg: let
mkHookEntry = name: value: ''
cat > $out/${name} <<'EOF'
#! ${pkgs.runtimeShell}
set -e
${value}
EOF
chmod 755 $out/${name}
'';
in pkgs.runCommand "buildkite-agent-hooks" { preferLocalBuild = true; } ''
mkdir $out
${concatStringsSep "\n" (mapAttrsToList mkHookEntry (filterAttrs (n: v: v != null) cfg.hooks))}
'';
buildkiteOptions = { name ? "", config, ... }: {
options = {
enable = mkOption {
default = true;
type = types.bool;
description = "Whether to enable this buildkite agent";
};
package = mkOption {
default = pkgs.buildkite-agent;
defaultText = "pkgs.buildkite-agent";
description = "Which buildkite-agent derivation to use";
type = types.package;
};
dataDir = mkOption {
default = "/var/lib/buildkite-agent-${name}";
description = "The workdir for the agent";
type = types.str;
};
runtimePackages = mkOption {
default = [ pkgs.bash pkgs.gnutar pkgs.gzip pkgs.git pkgs.nix ];
defaultText = "[ pkgs.bash pkgs.gnutar pkgs.gzip pkgs.git pkgs.nix ]";
description = "Add programs to the buildkite-agent environment";
type = types.listOf types.package;
};
tokenPath = mkOption {
type = types.path;
description = ''
The token from your Buildkite "Agents" page.
A run-time path to the token file, which is supposed to be provisioned
outside of Nix store.
'';
};
name = mkOption {
type = types.str;
default = "%hostname-${name}-%n";
description = ''
The name of the agent as seen in the buildkite dashboard.
'';
};
tags = mkOption {
type = types.attrsOf types.str;
default = {};
example = { queue = "default"; docker = "true"; ruby2 ="true"; };
description = ''
Tags for the agent.
'';
};
extraConfig = mkOption {
type = types.lines;
default = "";
example = "debug=true";
description = ''
Extra lines to be added verbatim to the configuration file.
'';
};
privateSshKeyPath = mkOption {
type = types.nullOr types.path;
default = null;
## maximum care is taken so that secrets (ssh keys and the CI token)
## don't end up in the Nix store.
apply = final: if final == null then null else toString final;
description = ''
OpenSSH private key
A run-time path to the key file, which is supposed to be provisioned
outside of Nix store.
'';
};
hooks = mkHookOptions [
{ name = "checkout";
description = ''
The `checkout` hook script will replace the default checkout routine of the
bootstrap.sh script. You can use this hook to do your own SCM checkout
behaviour
''; }
{ name = "command";
description = ''
The `command` hook script will replace the default implementation of running
the build command.
''; }
{ name = "environment";
description = ''
The `environment` hook will run before all other commands, and can be used
to set up secrets, data, etc. Anything exported in hooks will be available
to the build script.
Note: the contents of this file will be copied to the world-readable
Nix store.
'';
example = ''
export SECRET_VAR=`head -1 /run/keys/secret`
''; }
{ name = "post-artifact";
description = ''
The `post-artifact` hook will run just after artifacts are uploaded
''; }
{ name = "post-checkout";
description = ''
The `post-checkout` hook will run after the bootstrap script has checked out
your projects source code.
''; }
{ name = "post-command";
description = ''
The `post-command` hook will run after the bootstrap script has run your
build commands
''; }
{ name = "pre-artifact";
description = ''
The `pre-artifact` hook will run just before artifacts are uploaded
''; }
{ name = "pre-checkout";
description = ''
The `pre-checkout` hook will run just before your projects source code is
checked out from your SCM provider
''; }
{ name = "pre-command";
description = ''
The `pre-command` hook will run just before your build command runs
''; }
{ name = "pre-exit";
description = ''
The `pre-exit` hook will run just before your build job finishes
''; }
];
hooksPath = mkOption {
type = types.path;
default = hooksDir config;
defaultText = "generated from services.buildkite-agents.<name>.hooks";
description = ''
Path to the directory storing the hooks.
Consider using <option>services.buildkite-agents.&lt;name&gt;.hooks.&lt;name&gt;</option>
instead.
'';
};
shell = mkOption {
type = types.str;
default = "${pkgs.bash}/bin/bash -e -c";
description = ''
Command that buildkite-agent 3 will execute when it spawns a shell.
'';
};
};
};
enabledAgents = lib.filterAttrs (n: v: v.enable) cfg;
mapAgents = function: lib.mkMerge (lib.mapAttrsToList function enabledAgents);
in
{
options.services.buildkite-agents = mkOption {
type = types.attrsOf (types.submodule buildkiteOptions);
default = {};
description = ''
Attribute set of buildkite agents.
The attribute key is combined with the hostname and a unique integer to
create the final agent name. This can be overridden by setting the `name`
attribute.
'';
};
config.users.users = mapAgents (name: cfg: {
"buildkite-agent-${name}" = {
name = "buildkite-agent-${name}";
home = cfg.dataDir;
createHome = true;
description = "Buildkite agent user";
extraGroups = [ "keys" ];
isSystemUser = true;
group = "buildkite-agent-${name}";
};
});
config.users.groups = mapAgents (name: cfg: {
"buildkite-agent-${name}" = {};
});
config.systemd.services = mapAgents (name: cfg: {
"buildkite-agent-${name}" =
{ description = "Buildkite Agent";
wantedBy = [ "multi-user.target" ];
after = [ "network.target" ];
path = cfg.runtimePackages ++ [ cfg.package pkgs.coreutils ];
environment = config.networking.proxy.envVars // {
HOME = cfg.dataDir;
NIX_REMOTE = "daemon";
};
## NB: maximum care is taken so that secrets (ssh keys and the CI token)
## don't end up in the Nix store.
preStart = let
sshDir = "${cfg.dataDir}/.ssh";
tagStr = lib.concatStringsSep "," (lib.mapAttrsToList (name: value: "${name}=${value}") cfg.tags);
in
optionalString (cfg.privateSshKeyPath != null) ''
mkdir -m 0700 -p "${sshDir}"
cp -f "${toString cfg.privateSshKeyPath}" "${sshDir}/id_rsa"
chmod 600 "${sshDir}"/id_rsa
'' + ''
cat > "${cfg.dataDir}/buildkite-agent.cfg" <<EOF
token="$(cat ${toString cfg.tokenPath})"
name="${cfg.name}"
shell="${cfg.shell}"
tags="${tagStr}"
build-path="${cfg.dataDir}/builds"
hooks-path="${cfg.hooksPath}"
${cfg.extraConfig}
EOF
'';
serviceConfig =
{ ExecStart = "${cfg.package}/bin/buildkite-agent start --config ${cfg.dataDir}/buildkite-agent.cfg";
User = "buildkite-agent-${name}";
RestartSec = 5;
Restart = "on-failure";
TimeoutSec = 10;
# set a long timeout to give buildkite-agent a chance to finish current builds
TimeoutStopSec = "2 min";
KillMode = "mixed";
};
};
});
config.assertions = mapAgents (name: cfg: [
{ assertion = cfg.hooksPath == (hooksDir cfg) || all (v: v == null) (attrValues cfg.hooks);
message = ''
Options `services.buildkite-agents.${name}.hooksPath' and
`services.buildkite-agents.${name}.hooks.<name>' are mutually exclusive.
'';
}
]);
imports = [
(mkRemovedOptionModule [ "services" "buildkite-agent"] "services.buildkite-agent has been upgraded from version 2 to version 3 and moved to an attribute set at services.buildkite-agents. Please consult the 20.03 release notes for more information.")
];
}