chore(`check-for-changes.sh`): Drop redundant guards (#2623)

* chore: Remove requirement for `postfix-accounts.cf`

This is an old requirement from when the change detector service was first introduced. It's no longer relevant.

* chore: Do not needlessly create `postfix-aliases.cf`

The config was created regardless to workaround early change detection support. No longer necessary to require the file to exist.

* chore: Drop guards requiring `/tmp/docker-mailserver` to exist

Legacy guards when this was the only location change detection location supported.

There does not appear to be any need for changing into this directory at the start of `check-for-changes.sh` as we use absolute filepaths (originally monitored files were checked with relative paths to this config dir).

* chore: Revise inline docs

* chore: Add change detection monitoring for extra configs

These are also handled at run-time in the current change detection support, so it makes sense to allows these config updates to also trigger change events.

target/scripts/check-for-changes.sh

@@ -22,17 +22,6 @@ _log_with_date 'debug' 'Starting changedetector'
 #            to be properly set.
 _obtain_hostname_and_domainname
 
-if ! cd /tmp/docker-mailserver &>/dev/null
-then
-  _exit_with_error "Could not change into '/tmp/docker-mailserver/' directory" 0
-fi
-
-# check postfix-accounts.cf exist else break
-if [[ ! -f postfix-accounts.cf ]]
-then
-  _exit_with_error "'/tmp/docker-mailserver/postfix-accounts.cf' is missing" 0
-fi
-
 # verify checksum file exists; must be prepared by start-mailserver.sh
 if [[ ! -f ${CHKSUM_FILE} ]]
 then

target/scripts/helpers/aliases.sh

@@ -61,13 +61,8 @@ function _handle_postfix_aliases_config
 
   echo "root: ${POSTMASTER_ADDRESS}" >/etc/aliases
 
-  if [[ -f /tmp/docker-mailserver/postfix-aliases.cf ]]
-  then
-    cat /tmp/docker-mailserver/postfix-aliases.cf >>/etc/aliases
-  else
-    _log 'trace' "'/tmp/docker-mailserver/postfix-aliases.cf' is not provided, it will be auto created."
-    : >/tmp/docker-mailserver/postfix-aliases.cf
-  fi
+  local DATABASE_ALIASES='/tmp/docker-mailserver/postfix-aliases.cf'
+  [[ -f ${DATABASE_ALIASES} ]] && cat "${DATABASE_ALIASES}" >>/etc/aliases
 
   postalias /etc/aliases
 }

target/scripts/helpers/change-detection.sh

@@ -4,7 +4,7 @@
 # - check-for-changes.sh
 # - test/test_helper/common.bash:wait_for_changes_to_be_detected_in_container()
 # - test/test_helper.bats
-# - start-mailserver.sh --> setup-stack.sh (to initialize the CHKSUM_FILE state)
+# - start-mailserver.sh --> setup-stack.sh:_setup (to initialize the CHKSUM_FILE state)
 
 # Global checksum file used to track when monitored files have changed in content:
 # shellcheck disable=SC2034
@@ -16,38 +16,36 @@ function _prepare_for_change_detection
 {
   _log 'debug' 'Setting up configuration checksum file'
 
-  if [[ -d /tmp/docker-mailserver ]]
-  then
-    _log 'trace' "Creating '${CHKSUM_FILE}'"
-    _monitored_files_checksums >"${CHKSUM_FILE}"
-  else
-    # We could just skip the file, but perhaps config can be added later?
-    # If so it must be processed by the check for changes script
-    _log 'trace' "Creating empty '${CHKSUM_FILE}' (no config)"
-    touch "${CHKSUM_FILE}"
-  fi
+  _log 'trace' "Creating '${CHKSUM_FILE}'"
+  _monitored_files_checksums >"${CHKSUM_FILE}"
 }
 
 # Returns a list of changed files, each line is a value pair of:
 # <SHA-512 content hash> <changed file path>
 function _monitored_files_checksums
 {
-  local DMS_DIR=/tmp/docker-mailserver
-  [[ -d ${DMS_DIR} ]] || return 1
-
   # If a wildcard path pattern (or an empty ENV) would yield an invalid path
   # or no results, `shopt -s nullglob` prevents it from being added.
   shopt -s nullglob
   declare -a STAGING_FILES CHANGED_FILES
 
-  STAGING_FILES=(
-    "${DMS_DIR}/postfix-accounts.cf"
-    "${DMS_DIR}/postfix-virtual.cf"
-    "${DMS_DIR}/postfix-aliases.cf"
-    "${DMS_DIR}/dovecot-quotas.cf"
-    "${DMS_DIR}/dovecot-masters.cf"
-  )
+  # Supported user provided configs:
+  local DMS_DIR=/tmp/docker-mailserver
+  if [[ -d ${DMS_DIR} ]]
+  then
+    STAGING_FILES+=(
+      "${DMS_DIR}/postfix-accounts.cf"
+      "${DMS_DIR}/postfix-virtual.cf"
+      "${DMS_DIR}/postfix-regexp.cf"
+      "${DMS_DIR}/postfix-aliases.cf"
+      "${DMS_DIR}/postfix-relaymap.cf"
+      "${DMS_DIR}/postfix-sasl-password.cf"
+      "${DMS_DIR}/dovecot-quotas.cf"
+      "${DMS_DIR}/dovecot-masters.cf"
+    )
+  fi
 
+  # SSL certs:
   if [[ ${SSL_TYPE:-} == 'manual' ]]
   then
     # When using "manual" as the SSL type,
@@ -69,10 +67,11 @@ function _monitored_files_checksums
     )
   fi
 
+  # If the file actually exists, add to CHANGED_FILES
+  # and generate a content hash entry:
   for FILE in "${STAGING_FILES[@]}"
   do
     [[ -f "${FILE}" ]] && CHANGED_FILES+=("${FILE}")
   done
-
   sha512sum -- "${CHANGED_FILES[@]}"
 }