nixpkgs/nixos/modules/services/monitoring/prometheus/exporters/blackbox.nix
2020-03-06 01:43:20 +01:00

70 lines
2.2 KiB
Nix

{ config, lib, pkgs, options }:
with lib;
let
logPrefix = "services.prometheus.exporter.blackbox";
cfg = config.services.prometheus.exporters.blackbox;
# This ensures that we can deal with string paths, path types and
# store-path strings with context.
coerceConfigFile = file:
if (builtins.isPath file) || (lib.isStorePath file) then
file
else
(lib.warn ''
${logPrefix}: configuration file "${file}" is being copied to the nix-store.
If you would like to avoid that, please set enableConfigCheck to false.
'' /. + file);
checkConfigLocation = file:
if lib.hasPrefix "/tmp/" file then
throw
"${logPrefix}: configuration file must not reside within /tmp - it won't be visible to the systemd service."
else
true;
checkConfig = file:
pkgs.runCommand "checked-blackbox-exporter.conf" {
preferLocalBuild = true;
buildInputs = [ pkgs.buildPackages.prometheus-blackbox-exporter ];
} ''
ln -s ${coerceConfigFile file} $out
blackbox_exporter --config.check --config.file $out
'';
in {
port = 9115;
extraOpts = {
configFile = mkOption {
type = types.path;
description = ''
Path to configuration file.
'';
};
enableConfigCheck = mkOption {
type = types.bool;
default = true;
description = ''
Whether to run a correctness check for the configuration file. This depends
on the configuration file residing in the nix-store. Paths passed as string will
be copied to the store.
'';
};
};
serviceOpts = let
adjustedConfigFile = if cfg.enableConfigCheck then
checkConfig cfg.configFile
else
checkConfigLocation cfg.configFile;
in {
serviceConfig = {
AmbientCapabilities = [ "CAP_NET_RAW" ]; # for ping probes
ExecStart = ''
${pkgs.prometheus-blackbox-exporter}/bin/blackbox_exporter \
--web.listen-address ${cfg.listenAddress}:${toString cfg.port} \
--config.file ${escapeShellArg adjustedConfigFile} \
${concatStringsSep " \\\n " cfg.extraFlags}
'';
ExecReload = "${pkgs.coreutils}/bin/kill -HUP $MAINPID";
};
};
}