bundles/dovecot: add full text indexing

bundles/dovecot/files/dovecot.conf

@@ -40,7 +40,7 @@ login_greeting = IMAPd ready
 auth_mechanisms = plain login
 first_valid_uid = 65534
 disable_plaintext_auth = yes
-mail_plugins = $mail_plugins zlib old_stats
+mail_plugins = $mail_plugins zlib old_stats fts fts_xapian
 
 plugin {
     zlib_save_level = 6
@@ -56,6 +56,15 @@ plugin {
     old_stats_refresh = 30 secs
     old_stats_track_cmds = yes
 
+    fts = xapian
+    fts_xapian = partial=3 full=20
+
+    fts_autoindex = yes
+    fts_enforced = yes
+
+    # Index attachements
+    fts_decoder = decode2text
+
 % if node.has_bundle('rspamd'):
     sieve_before = /var/mail/vmail/sieve/global/spam-global.sieve
 
@@ -86,14 +95,19 @@ service auth {
     }
 }
 
-service lmtp {
-    unix_listener /var/spool/postfix/private/dovecot-lmtp {
-        group = postfix
-        mode = 0600
-        user = postfix
+service decode2text {
+    executable = script /usr/lib/dovecot/decode2text.sh
+    user = dovecot
+    unix_listener decode2text {
+        mode = 0666
     }
 }
 
+service indexer-worker {
+    vsz_limit = 0
+    process_limit = 0
+}
+
 service imap {
     executable = imap
 }
@@ -104,6 +118,14 @@ service imap-login {
     vsz_limit = 64M
 }
 
+service lmtp {
+    unix_listener /var/spool/postfix/private/dovecot-lmtp {
+        group = postfix
+        mode = 0600
+        user = postfix
+    }
+}
+
 service managesieve-login {
     inet_listener sieve {
         port = 4190