Documentation and Script Updates trying to fix #1647 (#1653)

* documentation and script updates trying to fix #1647
* re-trigger tests
* removing unnecessary rm statements
* re-trigger tests

README.md

@@ -19,7 +19,7 @@ A fullstack but simple mail server (SMTP, IMAP, Antispam, Antivirus...).
 Only configuration files, no SQL database. Keep it simple and versioned.
 Easy to deploy and upgrade.
 
-Why I created this image: [Simple Mail Server with Docker](http://tvi.al/simple-mail-server-with-docker/)
+[Why was this image was created?](http://tvi.al/simple-mail-server-with-docker/)
 
 1. [Announcements](#announcements)
 2. [Includes](#includes)
@@ -31,13 +31,14 @@ Why I created this image: [Simple Mail Server with Docker](http://tvi.al/simple-
 
 ## Announcements
 
-1. Debian Buster is now Docker base image
+1. Since version `v7.1.0`, the use of default variables has changed slightly. Please consult the [environment Variables](#environment-variables) sections
+2. Debian Buster is now Docker base image
    - Filebeat was removed
    - Dovecot was downgraded
-2. ELK was removed
+3. ELK was removed
-3. New contributing guidelines were added
+4. New contributing guidelines were added
-4. Added coherent coding style and linting
+5. Added coherent coding style and linting
-5. Added option to use non-default network interface
+6. Added option to use non-default network interface
 
 ## Includes
 
@@ -259,6 +260,8 @@ volumes:
 
 If an option doesn't work as documented here, check if you are running the latest image! Values in **bold** are the default values.
 
+**Note**: Since `docker-mailserver v7.1.0`, comparisons for environment variables are executed differently. If you previously used `VARIABLE=''` as the `empty` value, please **update** to now use `VARIABLE=`.
+
 ### Assignments
 
 #### General

target/start-mailserver.sh

@@ -982,7 +982,7 @@ function _setup_postfix_aliases
       DOMAIN=$(echo "${FROM}" | cut -d @ -f2)
 
       # if they are equal it means the line looks like: "user1     other@domain.tld"
-      [ "${UNAME}" != "${DOMAIN}" ] && echo "${DOMAIN}" >> /tmp/vhost.tmp
+      [[ ${UNAME} != "${DOMAIN}" ]] && echo "${DOMAIN}" >>/tmp/vhost.tmp
     done < <(grep -v "^\s*$\|^\s*\#" /tmp/docker-mailserver/postfix-virtual.cf || true)
   else
     _notify 'inf' "Warning 'config/postfix-virtual.cf' is not provided. No mail alias/forward created."
@@ -1483,14 +1483,14 @@ function _setup_postfix_dhparam
     if [[ ! -f ${DHPARAMS_FILE} ]]
     then
       _notify 'inf' "Use ffdhe4096 for dhparams (postfix)"
-      rm -f /etc/postfix/dhparams.pem && cp /etc/postfix/shared/ffdhe4096.pem /etc/postfix/dhparams.pem
+      cp -f /etc/postfix/shared/ffdhe4096.pem /etc/postfix/dhparams.pem
     else
       _notify 'inf' "Use postfix dhparams that was generated previously"
       _notify 'warn' "Using self-generated dhparams is considered as insecure."
       _notify 'warn' "Unless you known what you are doing, please remove /var/mail-state/lib-shared/dhparams.pem."
 
       # Copy from the state directory to the working location
-      rm -f /etc/postfix/dhparams.pem && cp "${DHPARAMS_FILE}" /etc/postfix/dhparams.pem
+      cp -f "${DHPARAMS_FILE}" /etc/postfix/dhparams.pem
     fi
   else
     if [[ ! -f /etc/postfix/dhparams.pem ]]
@@ -1528,14 +1528,14 @@ function _setup_dovecot_dhparam
     if [[ ! -f ${DHPARAMS_FILE} ]]
     then
       _notify 'inf' "Use ffdhe4096 for dhparams (dovecot)"
-      rm -f /etc/dovecot/dh.pem && cp /etc/postfix/shared/ffdhe4096.pem /etc/dovecot/dh.pem
+      cp -f /etc/postfix/shared/ffdhe4096.pem /etc/dovecot/dh.pem
     else
       _notify 'inf' "Use dovecot dhparams that was generated previously"
       _notify 'warn' "Using self-generated dhparams is considered as insecure."
       _notify 'warn' "Unless you known what you are doing, please remove /var/mail-state/lib-shared/dhparams.pem."
 
       # Copy from the state directory to the working location
-      rm -f /etc/dovecot/dh.pem && cp "${DHPARAMS_FILE}" /etc/dovecot/dh.pem
+      cp -f "${DHPARAMS_FILE}" /etc/dovecot/dh.pem
     fi
   else
     if [[ ! -f /etc/dovecot/dh.pem ]]
@@ -1545,14 +1545,14 @@ function _setup_dovecot_dhparam
         _notify 'inf' "Copy postfix dhparams to dovecot"
         cp /etc/postfix/dhparams.pem /etc/dovecot/dh.pem
       elif [[ -f /tmp/docker-mailserver/dhparams.pem ]]
-    then
+      then
         _notify 'inf' "Copy pre-generated dhparams to dovecot"
         _notify 'warn' "Using self-generated dhparams is considered as insecure."
         _notify 'warn' "Unless you known what you are doing, please remove /tmp/docker-mailserver/dhparams.pem."
 
         cp /tmp/docker-mailserver/dhparams.pem /etc/dovecot/dh.pem
       else
-    _notify 'inf' "Use ffdhe4096 for dhparams (dovecot)"
+        _notify 'inf' "Use ffdhe4096 for dhparams (dovecot)"
         cp /etc/postfix/shared/ffdhe4096.pem /etc/dovecot/dh.pem
       fi
     else