tvl-depot/ops/modules/irccat.nix
Florian Klink 46a2c75a59 docs(ops/irccat): link to credentials RFE
https://cl.tvl.fyi/c/depot/+/4264 did move merging config with secrets
into ExecStart=, which is tracked in an RFE upstream:

https://github.com/systemd/systemd/issues/19604#issuecomment-989279884

We didn't link to this so far, neither in the commit message, nor in a
comment.

Let's add a comment, so people know when we can undo this.

Change-Id: I7bed370b671093bb876592b4dccd562f1c256cd2
Reviewed-on: https://cl.tvl.fyi/c/depot/+/4326
Tested-by: BuildkiteCI
Autosubmit: flokli <flokli@flokli.de>
Reviewed-by: tazjin <mail@tazj.in>
Reviewed-by: grfn <grfn@gws.fyi>
2021-12-14 17:30:33 +00:00

61 lines
1.9 KiB
Nix

{ depot, config, lib, pkgs, ... }:
let
cfg = config.services.depot.irccat;
description = "irccat - forward messages to IRC";
# irccat expects to read its configuration from the *current
# directory*, and its configuration contains secrets.
#
# To make this work we construct the JSON configuration file and
# then recursively merge it with an on-disk secret using jq on
# service launch.
configJson = pkgs.writeText "irccat.json" (builtins.toJSON cfg.config);
# Right now, merging configuration file with secrets and running the main
# application needs to happen both in ExecStart=, due to
# https://github.com/systemd/systemd/issues/19604#issuecomment-989279884
mergeAndLaunch = pkgs.writeShellScript "merge-irccat-config" ''
if [ ! -f "$CREDENTIALS_DIRECTORY/secrets" ]; then
echo "irccat secrets file is missing"
exit 1
fi
# jq's * is the recursive merge operator
${pkgs.jq}/bin/jq -s '.[0] * .[1]' ${configJson} "$CREDENTIALS_DIRECTORY/secrets" \
> /var/lib/irccat/irccat.json
exec ${depot.third_party.irccat}/bin/irccat
'';
in {
options.services.depot.irccat = {
enable = lib.mkEnableOption description;
config = lib.mkOption {
type = lib.types.attrs; # varying value types
description = "Configuration structure (unchecked!)";
};
secretsFile = lib.mkOption {
type = lib.types.str;
description = "Path to the secrets file to be merged";
default = "/run/agenix/irccat";
};
};
config = lib.mkIf cfg.enable {
systemd.services.irccat = {
inherit description;
wantedBy = [ "multi-user.target" ];
serviceConfig = {
ExecStart = "${mergeAndLaunch}";
DynamicUser = true;
StateDirectory = "irccat";
WorkingDirectory = "/var/lib/irccat";
LoadCredential = "secrets:${cfg.secretsFile}";
Restart = "always";
};
};
};
}