nix-bitcoin/test/lib/shellcheck-services.nix
2022-12-18 20:01:52 +01:00

128 lines
4.2 KiB
Nix

{ config, pkgs, lib, extendModules, ... }@args:
with lib;
let
options.test.shellcheckServices = {
enable = mkOption {
type = types.bool;
default = false;
description = ''
Whether to shellcheck services during system build time.
'';
};
sourcePrefix = mkOption {
type = with types; nullOr str;
default = null;
description = ''
The definition source path prefix of services to include in the shellcheck.
'';
};
runShellcheck = mkOption {
readOnly = true;
description = ''
A derivation that runs shellcheck on all bash scripts included
in nix-bitcoin services.
'';
default = shellcheckServices;
};
};
cfg = config.test.shellcheckServices;
# A list of all service names that are defined in source paths prefixed by
# `sourcePrefix`.
# [ "bitcoind", "clightning", ... ]
#
# Algorithm: Parse defintions of `systemd.services` and return all services
# that only have definitions located within `sourcePrefix`.
servicesToCheck = let
inherit (cfg) sourcePrefix;
systemdServices = args.options.systemd.services;
configSystemdServices = args.config.systemd.services;
matchingServices = collectServices true;
nonMatchingServices = collectServices false;
# Return set of services ({ service1 = true; service2 = true; ... })
# which are either defined or not defined within `sourcePrefix`, depending
# on `shouldMatch`.
collectServices = shouldMatch: lib.listToAttrs (builtins.concatLists (map (def:
let
services = def.value;
inherit (def) file;
isMatching = lib.hasPrefix sourcePrefix file;
in
# Nix has no boolean XOR, so use `if`
lib.optionals (if shouldMatch then isMatching else !isMatching) (
(map (service: { name = service; value = true; }) (builtins.attrNames services))
)
) systemdServices.definitionsWithLocations));
in
# Calculate set difference: matchingServices - nonMatchingServices
# and exclude unavailable services (defined via `mkIf false ...`) by checking `configSystemdServices`.
builtins.filter (prefixedService:
configSystemdServices ? ${prefixedService} && (! nonMatchingServices ? ${prefixedService})
) (builtins.attrNames matchingServices);
# The concatenated list of values of ExecStart, ExecStop, ... (`scriptAttrs`) of all `servicesToCheck`.
serviceCmds = let
scriptAttrs = [
"ExecStartPre"
"ExecStart"
"ExecStartPost"
"ExecStop"
"ExecStopPost"
"ExecCondition"
"ExecReload"
];
services = config.systemd.services;
in
builtins.concatMap (serviceName: let
serviceCfg = services.${serviceName}.serviceConfig;
in
builtins.concatMap (attr:
lib.optionals (serviceCfg ? ${attr}) (
let
cmd = serviceCfg.${attr};
in
if builtins.typeOf cmd == "list" then cmd else [ cmd ]
)
) scriptAttrs
) servicesToCheck;
# A list of all binaries included in `serviceCmds`
serviceBinaries = map (cmd: builtins.head (
# Extract the first component (the binary).
# cmd can start with extra modifiers like `+`
builtins.match "[^/]*([^[:space:]]+).*" (toString cmd)
)) serviceCmds;
shellcheckServices = pkgs.runCommand "shellcheck-services" {
inherit serviceBinaries;
# The `builtins.match` in `serviceBinaries` discards the string context, so we
# also have to add `serviceCmds` to the derivation. This ensures that all
# referenced nix paths are available to the builder.
inherit serviceCmds;
} ''
echo "Checked binaries:"
# Find and check all binaries that have a bash shebang
grep -Pl '\A#! *\S+bash\b' $serviceBinaries | while IFS= read -r script; do
echo "$script"
${pkgs.shellcheck}/bin/shellcheck --shell bash "$script"
done | tee "$out"
'';
in
{
inherit options;
config = mkIf (cfg.enable && cfg.sourcePrefix != null) {
assertions = [
{
assertion = builtins.length servicesToCheck > 0;
message = "test.shellcheckServices: No services found with source prefix `${cfg.sourcePrefix}`";
}
];
system.extraDependencies = [ shellcheckServices ];
};
}