X-Git-Url: http://git.scottworley.com/nix-profile-gc/blobdiff_plain/10533fbd6bdf5046f36e41c7848dbc6a324eb4cd..565acdea12c86a788031778b96fc5e111ce957b9:/modules/profile-gc.nix?ds=sidebyside

diff --git a/modules/profile-gc.nix b/modules/profile-gc.nix
index 8e69301..e2f0e3d 100644
--- a/modules/profile-gc.nix
+++ b/modules/profile-gc.nix
@@ -1,3 +1,18 @@
+# nix-profile-gc: More gently remove old profiles
+# Copyright (C) 2022 Scott Worley <scottworley@scottworley.com>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, version 3.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
 { lib, config, pkgs, ... }:
 let
   inherit (lib) escapeShellArg;
@@ -7,14 +22,27 @@ let
     parsed=$(systemd-analyze timespan ${escapeShellArg duration} | awk '$1 == "μs:" { print $2 }')
     echo "$parsed" > "$out"
   '';
+  gather_home_profiles = lib.optionalString cfg.manageHomeProfiles ''
+    while read -r home_dir;do
+      home_profile_dir="$home_dir/.local/state/nix/profiles"
+      if [[ -d "$home_profile_dir" ]];then
+        home_profile_dirs+=( "$home_profile_dir" )
+      fi
+    done < <(${pkgs.coreutils}/bin/cut -d: -f6 /etc/passwd | ${pkgs.coreutils}/bin/sort -u)
+  '';
 in {
   options = {
     nix.profile-gc = {
       enable = lib.mkEnableOption "Automatic profile garbage collection";
+      manageHomeProfiles = lib.mkOption {
+        description = "Manage profiles in users' $HOME/.local/state/nix/profiles/";
+        type = lib.types.bool;
+        default = false;  # Will flip to true later
+      };
       dryRun = lib.mkOption {
         description = "Say what would have been deleted rather than actually deleting profiles";
         type = lib.types.bool;
-        default = true;
+        default = false;
       };
       keepLast = lib.mkOption {
         description = ''
@@ -49,16 +77,23 @@ in {
           awhile (so keepLatest won't protect them) generates a bunch of broken profiles (so
           keepLast won't protect them) while trying to get up to date.
 
-          This is approximate and has a useful granularity of an hour
-          (config.systemd.timers.profile-gc-log-active.timerConfig.OnUnitActiveSec).
-          Do not set less than this.
+          This threshold is approximate, see activeMeasurementGranularity.
+          Do not set less than activeMeasurementGranularity!
         '';
-        # We admonish the user "Do not set less than this." and check it at runtime rather
-        # than verifying this with an assertion now because parsing these durations at
-        # configuration-time requires import-from-derivation, which we want to avoid.  :(
+        # We admonish the user "Do not set less than activeMeasurementGranularity!" and check
+        # it at runtime rather than verifying this with an assertion at evaluation time because
+        # parsing these durations at evaluation-time requires import-from-derivation, which we
+        # want to avoid.  :(
         type = lib.types.str;
         default = "5 days";
       };
+      activeMeasurementGranularity = lib.mkOption {
+        description = ''
+          How often to make a note of the currently-active profiles.  This is the useful
+          granularity and minimum value of activeThreshold.
+        '';
+        default = "1 hour";
+      };
       keepLatest = lib.mkOption {
         description = ''
           Keep all profiles younger than this duration (systemd.time format).
@@ -98,7 +133,7 @@ in {
       fi
 
       alive_threshold="$(< ${parse-duration cfg.activeThreshold})"
-      alive_loginterval="$(< ${parse-duration config.systemd.timers.profile-gc-log-active.timerConfig.OnUnitActiveSec})"
+      alive_loginterval="$(< ${parse-duration cfg.activeMeasurementGranularity})"
       if (( alive_threshold < alive_loginterval ));then
         echo "Liveness threshold is too low.  Not doing any profile garbage collection." >&2
         exit 0
@@ -131,21 +166,24 @@ in {
       }
 
       declare -A active_targets
-      while read target;do
+      while read -r target;do
         active_targets[$target]=1
       done < <(
         verbose_topn ${cfg.logdir}/active-system "" ${escapeShellArg cfg.keepLastActiveSystem}
         verbose_topn ${cfg.logdir}/active-boot   "" ${escapeShellArg cfg.keepLastActiveBoot  }
       )
 
+      home_profile_dirs=()
+      ${gather_home_profiles}
+
       now=$(${pkgs.coreutils}/bin/date +%s)
       age_threshold="$(< ${parse-duration cfg.keepLatest})"
-      while read profile;do
+      while read -r profile;do
         echo "Contemplating profiles for $profile:" >&2
         unset active
         declare -A active
-        while read p;do
-          active[$p]=1
+        while read -r pname;do
+          active[$pname]=1
         done < <(verbose_topn ${cfg.logdir}/active-profiles "$profile" ${escapeShellArg cfg.keepLastActive})
         current=$(${pkgs.coreutils}/bin/readlink "$profile")
         currentgen=''${current%-link}
@@ -157,15 +195,16 @@ in {
             echo "(Disregarding unrelated profile $p)" >&2
             continue
           fi
-          if [[ "$p" == "$current" ]];then
+          pname=$(${pkgs.coreutils}/bin/basename "$p")
+          if [[ "$pname" == "$current" ]];then
             echo "Keeeping current profile $p" >&2
             continue
           fi
-          if [[ "''${active_targets[$(${pkgs.coreutils}/bin/readlink "$p")]}" ]];then
+          if [[ "''${active_targets[$(${pkgs.coreutils}/bin/readlink "$p")]:-}" ]];then
             echo "Keeeping active system/boot profile $p" >&2
             continue
           fi
-          if [[ "''${active[$p]}" ]];then
+          if [[ "''${active[$pname]:-}" ]];then
             echo "Keeeping active profile $p" >&2
             continue
           fi
@@ -186,21 +225,25 @@ in {
             rm "$p"
           ''}
         done
-      done < <(${pkgs.findutils}/bin/find ''${NIX_STATE_DIR:-/nix/var/nix}/profiles/ -type l -not -name '*[0-9]-link')
+      done < <(${pkgs.findutils}/bin/find "''${NIX_STATE_DIR:-/nix/var/nix}/profiles/" "''${home_profile_dirs[@]}" -type l -not -name '*[0-9]-link')
     '';
     systemd.timers.profile-gc-log-active = {
       wantedBy = [ "timers.target" ];
-      timerConfig.OnUnitActiveSec = "1 hour";
+      timerConfig.OnActiveSec = cfg.activeMeasurementGranularity;
+      timerConfig.OnUnitActiveSec = cfg.activeMeasurementGranularity;
     };
     systemd.services.profile-gc-log-active = {
       description =
         "Log the active profiles for gc collection policy evaluation";
       serviceConfig.Type = "oneshot";
       script = ''
+        home_profile_dirs=()
+        ${gather_home_profiles}
+
         ${pkgs.coreutils}/bin/mkdir -p ${cfg.logdir}
         ${pkgs.coreutils}/bin/readlink /run/current-system >> ${cfg.logdir}/active-system
         ${pkgs.coreutils}/bin/readlink /run/booted-system  >> ${cfg.logdir}/active-boot
-        ${pkgs.findutils}/bin/find ''${NIX_STATE_DIR:-/nix/var/nix}/profiles/ \
+        ${pkgs.findutils}/bin/find ''${NIX_STATE_DIR:-/nix/var/nix}/profiles/ "''${home_profile_dirs[@]}" \
           -type l -not -name '*[0-9]-link' \
           -exec ${pkgs.stdenv.shell} -c '
             for f;do