Install and remove package without error even if no database

distros/debian8/zoneminder.config

@@ -17,61 +17,62 @@ if [ "$1" = "configure" ]; then
 
     # Exit if the user does not want to use debconf
     db_get zoneminder/debconf_install
-    if [ "$RET" = "false" ]; then
-        exit 0
-    fi
+    [ "$RET" = "false" ] && exit 0
+    dbc_install="$RET"
 fi
 
 # Source the config file if exists
 if [ -e $CONFIGFILE ]; then
     . $CONFIGFILE || true
 else
-    # Exit with error if no config file
+    # Display a message if no config file
     db_input high zoneminder/debconf_confmissingerror || true
     db_go || true
-    exit 1
 fi
 
 if [ ! "$ZM_DB_TYPE" = "mysql" ]; then
-    # Exit with error, currently we only support mysql
+    # Display a message if wrong database type
     db_input high zoneminder/debconf_dbtypeerror || true
     db_go || true
-    exit 1
 fi
 
+DB_OK=false
+
 # Ask the user if the database shall be installed locally or remotely
 db_input high zoneminder/debconf_dblocation || true
 db_go || true
 db_get zoneminder/debconf_dblocation
 if [ "$RET" = "local" ]; then
     if [ ! -e "/usr/sbin/mysqld" ]; then
-        # Display a message and exit if the user want a local database but no
-        # database server is available
+        # Display a message if the user want a local database but no database
+        # server is available
         db_input high zoneminder/debconf_dblocalmissingerror || true
         db_go || true
-        exit 1
+    else
+        DB_OK=true
+        # Set the database server to localhost
+        dbc_dbserver="localhost"
     fi
-    # Set the database server to localhost
-    dbc_dbserver="localhost"
 else
     # Source the dbconfig main configuration file
     if [ -f /etc/dbconfig-common/config ]; then
         . /etc/dbconfig-common/config
     fi
     if [ "$dbc_remote_questions_default" = "false" ]; then
-        # Display a message and exit if the dbconfig configuration does not allow
+        # Display a message if the dbconfig configuration does not allow
         # installation of databases on remote servers from this assistant
-        # Note: It would be nice to override the default configuration by setting
-        # dbc_remote_questions_default to true here but unfortunately this does
-        # not work
+        # Note: It would be nice to override the default configuration by
+        # setting dbc_remote_questions_default to true here but unfortunately
+        # this does not work
         # https://bugs.launchpad.net/ubuntu/+source/dbconfig-common/+bug/1065331
         db_input high zoneminder/debconf_dbconfigerror || true
         db_go || true
-        exit 1
+    else
+        DB_OK=true
     fi
 fi
 
-if [ -f /usr/share/dbconfig-common/dpkg/config ]; then
+if [ "$DB_OK" = "true" ] && [ -f /usr/share/dbconfig-common/dpkg/config ]; then
 
     # Set the first version in which dbconfig-common was introduced in the
     # package

distros/debian8/zoneminder.postinst

@@ -50,11 +50,10 @@ mysql_update() {
 
 # Exit if user didn't want to use debconf
 db_get zoneminder/debconf_install
-if [ "$RET" = "false" ]; then
-    exit 0;
-fi
+[ "$RET" = "false" ] && exit 0
 
 # Source the config file if exists
+[ ! -e $CONFIGFILE ] && exit 0
 . $CONFIGFILE
 
 if [ -f /usr/share/dbconfig-common/dpkg/postinst ]; then
@@ -152,8 +151,15 @@ if [ "$1" = "configure" ]; then
     # Ensure zoneminder is stopped
     deb-systemd-invoke stop zoneminder.service || exit $?
 
-    # Run the ZoneMinder update tool
-    zmupdate.pl
+    # If mysql server exists and is running
+    if [ -e "/usr/sbin/mysqld" ] && deb-systemd-invoke start mysql.service; then
+        # Run the ZoneMinder update tool
+        zmupdate.pl
+    else
+        # Otherwise exit without error (mysql server may not be available on
+        # this machine)
+        exit 0;
+    fi
 fi
 
 #DEBHELPER#