diff options
Diffstat (limited to 'system/services/nix-sync/default.nix')
| -rw-r--r-- | system/services/nix-sync/default.nix | 193 |
1 files changed, 193 insertions, 0 deletions
diff --git a/system/services/nix-sync/default.nix b/system/services/nix-sync/default.nix new file mode 100644 index 0000000..18511b3 --- /dev/null +++ b/system/services/nix-sync/default.nix @@ -0,0 +1,193 @@ +{ + config, + lib, + pkgs, + ... +}: let + cfg = config.services.nix-sync; + + mkUnit = name: repo: let + esa = lib.strings.escapeShellArg; + execStartScript = lib.writeShellScript "git-sync-exec" '' + cd ${esa cfg.cachePath}/${esa repo.path}; + + while true; do + origin="$(git rev-parse @{u})"; + branch="$(git rev-parse @)"; + + if ! [ "$origin" = "$branch" ]; then + git pull; + + out_paths=$(mktemp); + nix build . --print-out-paths --experimental-features 'nix-command flakes' > "$out_paths"; + [ "$(wc -l < "$out_paths")" -gt 1 ] && (echo "To many out-paths"; exit 1) + out_path="$(cat "$out_paths")"; + rm -r ${esa repo.path}; + ln -s "$out_path" ${esa repo.path}; + rm "$out-paths"; + fi + sleep ${esa repo.interval}; + done + ''; + execStartPreScript = '' + if ! stat ${esa cfg.cachePath}/${esa repo.path}/.git; then + mkdir --parents ${esa cfg.cachePath}/${esa repo.path}; + git clone ${esa repo.uri} ${esa cfg.cachePath}/${esa repo.path}; + + out_paths=$(mktemp); + nix build ${esa cfg.cachePath}/${esa repo.path} --print-out-paths --experimental-features 'nix-command flakes' > "$out_paths"; + [ "$(wc -l < "$out_paths")" -gt 1 ] && (echo "To many out-paths"; exit 1) + out_path="$(cat "$out_paths")"; + ln -s "$out_path" ${esa repo.path}; + rm "$out-paths"; + fi + ''; + in { + description = "Nix Sync ${name}"; + wantedBy = ["default.target"]; + after = ["network.target"]; + path = with pkgs; [openssh git nix mktemp coreutils]; + preStart = execStartPreScript; + + serviceConfig = { + ExecStart = execStartScript; + Restart = "on-abort"; + # User and group + User = cfg.user; + Group = cfg.group; + # Runtime directory and mode + RuntimeDirectory = "nginx"; + RuntimeDirectoryMode = "0750"; + # Cache directory and mode + CacheDirectory = "nginx"; + CacheDirectoryMode = "0750"; + # Logs directory and mode + LogsDirectory = "nginx"; + LogsDirectoryMode = "0750"; + # Proc filesystem + ProcSubset = "pid"; + ProtectProc = "invisible"; + # New file permissions + UMask = "0027"; # 0640 / 0750 + # Capabilities + AmbientCapabilities = ["CAP_CHOWN"]; + CapabilityBoundingSet = ["CAP_CHOWN"]; + # Security + NoNewPrivileges = true; + # Sandboxing (sorted by occurrence in https://www.freedesktop.org/software/systemd/man/systemd.exec.html) + ReadWritePaths = ["${repo.path}" "${cfg.cachePath}/${repo.path}"]; + ProtectSystem = "strict"; + ProtectHome = true; + PrivateTmp = true; + PrivateDevices = true; + ProtectHostname = true; + ProtectClock = true; + ProtectKernelTunables = true; + ProtectKernelModules = true; + ProtectKernelLogs = true; + ProtectControlGroups = true; + RestrictAddressFamilies = ["AF_UNIX" "AF_INET" "AF_INET6"]; + RestrictNamespaces = true; + LockPersonality = true; + MemoryDenyWriteExecute = true; + RestrictRealtime = true; + RestrictSUIDSGID = true; + RemoveIPC = true; + PrivateMounts = true; + # System Call Filtering + SystemCallArchitectures = "native"; + SystemCallFilter = ["~@cpu-emulation @debug @keyring @mount @obsolete @privileged @setuid"]; + }; + }; + + services = + lib.mapAttrs' (name: repo: { + name = "git-sync-${name}"; + value = mkUnit name repo; + }) + cfg.repositories; + + repositoryType = lib.types.submodule ({name, ...}: { + options = { + name = lib.mkOption { + internal = true; + default = name; + type = lib.types.str; + description = "The name that should be given to this unit."; + }; + + path = lib.mkOption { + type = lib.types.str; + description = "The path at which to sync the repository"; + }; + + uri = lib.mkOption { + type = lib.types.str; + example = "git+ssh://user@example.com:/~[user]/path/to/repo.git"; + description = '' + The URI of the remote to be synchronized. This is only used in the + event that the directory does not already exist. See + <link xlink:href="https://git-scm.com/docs/git-clone#_git_urls"/> + for the supported URIs. + ''; + }; + + interval = lib.mkOption { + type = lib.types.int; + default = 500; + description = '' + The interval, specified in seconds, at which the synchronization will + be triggered even without filesystem changes. + ''; + }; + }; + }); +in { + options = { + services.git-sync = { + enable = lib.mkEnableOption "git-sync services"; + + package = lib.mkOption { + type = lib.types.package; + default = pkgs.git-sync; + defaultText = lib.literalExpression "pkgs.git-sync"; + description = '' + Package containing the <command>git-sync</command> program. + ''; + }; + + user = lib.mkOption { + type = lib.types.str; + default = "nix-sync"; + description = lib.mdDoc "User account under which nix-sync units runs."; + }; + + group = lib.mkOption { + type = lib.types.str; + default = "nix-sync"; + description = lib.mdDoc "Group account under which nix-sync units runs."; + }; + + cachePath = lib.mkOption { + type = lib.types.str; + default = "/var/lib/nix-sync"; + description = lib.mdDoc '' + Where to cache git directories. + ''; + }; + + repositories = lib.mkOption { + type = with lib.types; attrsOf repositoryType; + description = '' + The repositories that should be synchronized. + ''; + }; + }; + }; + + config = lib.mkIf cfg.enable { + systemd.services = services; + }; +} +# vim: ts=2 + |