prevent apt from asking the user any questions

Add additional options to really prevent apt from asking questions, which causes setup to hang because stdin/out have been redirected.

fixes #270, #291

CHANGELOG.md

@@ -34,6 +34,7 @@ Setup:
 * Install cron if it isn't already installed.
 * Fix a units problem in the minimum memory check.
 * If you override the STORAGE_ROOT, your setting will now persist if you re-run setup.
+* Hangs due to apt wanting the user to resolve a conflict should now be fixed (apt will just clobber the problematic file now).
 
 v0.06 (January 4, 2015)
 -----------------------

setup/functions.sh

@@ -22,6 +22,20 @@ function hide_output {
 	rm -f $OUTPUT
 }
 
+function apt_get_quiet {
+	# Run apt-get in a totally non-interactive mode.
+	#
+	# Somehow all of these options are needed to get it to not ask the user
+	# questions about a) whether to proceed (-y), b) package options (noninteractive),
+	# and c) what to do about files changed locally (we don't cause that to happen but
+	# some VM providers muck with their images; -o).
+	#
+	# Although we could pass -qq to apt-get to make output quieter, many packages write to stdout
+	# and stderr things that aren't really important. Use our hide_output function to capture
+	# all of that and only show it if there is a problem (i.e. if apt_get returns a failure exit status).
+	DEBIAN_FRONTEND=noninteractive hide_output apt-get -y -o Dpkg::Options::="--force-confdef" -o Dpkg::Options::="--force-confnew" "$@"
+}
+
 function apt_install {
 	# Report any packages already installed.
 	PACKAGES=$@
@@ -46,18 +60,10 @@ function apt_install {
 		echo installing $TO_INSTALL...
 	fi
 
-	# 'DEBIAN_FRONTEND=noninteractive' is to prevent dbconfig-common from asking you questions.
-	#
-	# Although we could pass -qq to apt-get to make output quieter, many packages write to stdout
-	# and stderr things that aren't really important. Use our hide_output function to capture
-	# all of that and only show it if there is a problem (i.e. if apt_get returns a failure exit status).
-	#
-	# Also note that we still include the whole original package list in the apt-get command in
+	# We still include the whole original package list in the apt-get command in
 	# case it wants to upgrade anything, I guess? Maybe we can remove it. Doesn't normally make
 	# a difference.
-	DEBIAN_FRONTEND=noninteractive \
-	hide_output \
-	apt-get -y install $PACKAGES
+	apt_get_quiet install $PACKAGES
 }
 
 function get_default_hostname {

setup/network-checks.sh

 # Install the 'host', 'sed', and and 'nc' tools. This script is run before
 # the rest of the system setup so we may not yet have things installed.
-hide_output apt-get -y install bind9-host sed netcat-openbsd
+apt_get_quiet install bind9-host sed netcat-openbsd
 
 # Stop if the PRIMARY_HOSTNAME is listed in the Spamhaus Domain Block List.
 # The user might have chosen a name that was previously in use by a spammer

setup/questions.sh

@@ -4,7 +4,7 @@ if [ -z "$NONINTERACTIVE" ]; then
 	# e.g. if we piped a bootstrapping install script to bash to get started. In that
 	# case, the nifty '[ -t 0 ]' test won't work. But with Vagrant we must suppress so we
 	# use a shell flag instead. Really supress any output from installing dialog.
-	hide_output apt-get -y install dialog
+	apt_get_quiet install dialog
 	message_box "Mail-in-a-Box Installation" \
 		"Hello and thanks for deploying a Mail-in-a-Box!
 		\n\nI'm going to ask you a few questions.

setup/system.sh

@@ -9,7 +9,7 @@ source setup/functions.sh # load our functions
 
 echo Updating system packages...
 hide_output apt-get update
-hide_output apt-get -y upgrade
+apt_get_quiet upgrade
 
 # Install basic utilities.
 #