introduce imap_rawlog option for debugging

CHANGELOG.md

@@ -2,6 +2,11 @@
 
 ## untagged 
 
+- add optional "imap_rawlog" config option. If true, 
+  .in/.out files are created in user home dirs 
+  containing the imap protocol messages. 
+  ([#389](https://github.com/deltachat/chatmail/pull/389))
+
 ## 1.4.0 2024-07-28
 
 - Add `disable_ipv6` config option to chatmail.ini.

chatmaild/src/chatmaild/config.py

@@ -31,6 +31,7 @@ def __init__(self, inipath, params):
         self.filtermail_smtp_port = int(params["filtermail_smtp_port"])
         self.postfix_reinject_port = int(params["postfix_reinject_port"])
         self.disable_ipv6 = params.get("disable_ipv6", "false").lower() == "true"
+        self.imap_rawlog = params.get("imap_rawlog", "false").lower() == "true"
         self.iroh_relay = params.get("iroh_relay")
         self.privacy_postal = params.get("privacy_postal")
         self.privacy_mail = params.get("privacy_mail")

chatmaild/src/chatmaild/ini/chatmail.ini.f

@@ -54,6 +54,17 @@
 # if set to "True" IPv6 is disabled
 disable_ipv6 = False
 
+#
+# Debugging options 
+#
+
+# set to True if you want to track imap protocol execution
+# in per-maildir ".in/.out" files. 
+# Note that you need to manually cleanup these files
+# so use this option with caution on production servers. 
+imap_rawlog = false 
+
+
 #
 # Privacy Policy
 #

cmdeploy/src/cmdeploy/dovecot/dovecot.conf.j2

@@ -203,3 +203,24 @@ ssl_key = </var/lib/acme/live/{{ config.mail_domain }}/privkey
 ssl_dh = </usr/share/dovecot/dh.pem
 ssl_min_protocol = TLSv1.2
 ssl_prefer_server_ciphers = yes
+
+
+{% if config.imap_rawlog %}
+service postlogin {
+  executable = script-login -d rawlog
+  unix_listener postlogin {
+ }  
+} 
+service imap {
+  executable = imap postlogin 
+} 
+
+protocol imap { 
+  #rawlog_dir = /tmp/rawlog/%u
+  # Put .in and .out imap protocol logging files into per-user homedir 
+  # You can use a command like this to combine into one protocol stream:
+  # sort -sn <(sed 's/ / C: /' *.in) <(sed 's/ / S: /' cat *.out)
+
+  rawlog_dir = %h 
+} 
+{% endif %}