Add dovecot sieves to automatically learn spam and ham in RSpamD by moving in and out of spam folder.

roles/mailserver/files/etc_dovecot_conf.d_90-sieve.conf

   sieve = ~/.dovecot.sieve
   sieve_dir = ~/sieve
   sieve_before = /etc/dovecot/sieve/before.d
+  sieve_plugins = sieve_imapsieve sieve_extprograms
+
+  ###
+  ### Spam learning
+  ###
+  # From elsewhere to Spam folder
+  imapsieve_mailbox1_name = Junk
+  imapsieve_mailbox1_causes = COPY
+  imapsieve_mailbox1_before = file:/etc/dovecot/sieve/learn_spam.sieve
+
+  # From Spam folder to elsewhere
+  imapsieve_mailbox2_name = *
+  imapsieve_mailbox2_from = Junk
+  imapsieve_mailbox2_causes = COPY
+  imapsieve_mailbox2_before = file:/etc/dovecot/sieve/learn_ham.sieve
+
+  sieve_pipe_bin_dir = /usr/bin
+  sieve_global_extensions = +vnd.dovecot.pipe
 }

roles/mailserver/files/etc_dovecot_sieve_before.d_no-spam.sieve

 require "fileinto";
 require "imap4flags";
 
+if header :contains "X-Spam-Flag" "YES" {
+    setflag "\\seen";
+    fileinto "Junk";
+    stop;
+}
+
 if header :is "X-Spam" "Yes" {
     setflag "\\seen";
     fileinto "Junk";

roles/mailserver/files/etc_dovecot_sieve_learn_ham.sieve

+require ["vnd.dovecot.pipe", "copy", "imapsieve", "environment", "variables"];
+
+if environment :matches "imap.mailbox" "*" {
+    set "mailbox" "${1}";
+}
+
+if string "${mailbox}" "Trash" {
+    stop;
+}
+
+pipe :copy "rspamc" ["learn_ham"];

roles/mailserver/files/etc_dovecot_sieve_learn_spam.sieve

+require ["vnd.dovecot.pipe", "copy", "imapsieve"];
+pipe :copy "rspamc" ["learn_spam"];

roles/mailserver/tasks/dovecot.yml

     group=dovecot
   notify: restart dovecot
 
+- name: Configure learning spam sieve script
+  copy:
+    src=etc_dovecot_sieve_learn_spam.sieve
+    dest=/etc/dovecot/sieve/learn_spam.sieve
+    owner=vmail
+    group=dovecot
+  notify: restart dovecot
+
+- name: Configure learning ham sieve script
+  copy:
+    src=etc_dovecot_sieve_learn_ham.sieve
+    dest=/etc/dovecot/sieve/learn_ham.sieve
+    owner=vmail
+    group=dovecot
+  notify: restart dovecot
+
 - name: Copy additional Dovecot configuration files in place
   copy:
     src=etc_dovecot_conf.d_{{ item }}