Move indexDir option to the mailserver scopelewo/indexDir

This option has been initially in the mailserver.fullTextSearch
scope. However, this option modifies the location of all index files
of dovecot and not only those used by the full text search feature. It
is then more relevant to have this option in the mailserver top level
scope.

Moreover, the default option has been changed to null in order to keep
existing index files where they are: changing the index location means
recreating all index files. The fts documentation however recommend to
change this default location when enabling the fts feature.

1 files changed, 20 insertions, 8 deletions

diff --git a/default.nix b/default.nix
index 21c38e3..8905c5a 100644
--- a/default.nix
+++ b/default.nix
@@ -187,17 +187,29 @@ in
       default = {};
     };
 
+    indexDir = mkOption {
+      type = types.nullOr types.str;
+      default = null;
+      description = ''
+        Folder to store search indices. If null, indices are stored
+        along with email, which could not necessarily be desirable,
+        especially when the fullTextSearch option is enable since
+        indices it creates are voluminous and do not need to be backed
+        up.
+
+        Be careful when changing this option value since all indices
+        would be recreated at the new location (and clients would need
+        to resynchronize).
+
+        Note the some variables can be used in the file path. See
+        https://doc.dovecot.org/configuration_manual/mail_location/#variables
+        for details.
+      '';
+      example = "/var/lib/docecot/indices/%d/%n";
+    };
 
     fullTextSearch = {
       enable = mkEnableOption "Full text search indexing with xapian. This has significant performance and disk space cost.";
-      indexDir = mkOption {
-        type = types.nullOr types.str;
-        default = "/var/lib/dovecot/fts_xapian";
-        description = ''
-          Folder to store search indices. If null, indices are stored along with email, which
-          is not necessarily desirable as indices are voluminous and do not need to be backed up.
-        '';
-      };
       autoIndex = mkOption {
         type = types.bool;
         default = true;