create/init: add init-time env vars and gate and define one for zyppe…

…r weak deps

In case one really wants for recommended packages to stay disabled in an
opensuse image, make it possible to control this with an environment
variable. It's called DBX_CONTAINER_INIT_ZYPPER_NORECOMMENDS and must be
defined to either 'false' (i.e., the default, as we do want recommended
packages) or 'true'.

The variable, if present, is defined inside the environment of the
container. Then, in distrobox-init, we can check if it is there, and act
accordingly. So, for keeping recommended packages out, something like
this should be done:

  DBX_CONTAINER_INIT_ZYPPER_NORECOMMENDS=true distrobox create ...

While there, implement this in a bit more of a generic way. Basically,
all variables with a name that starts with DBX_CONTAINER_INIT_* that
distrobox-create finds defined, are included in the environment of the
container, so that distrobox-init can take advantage of them, to further
customize things.

This is somewhat similar to #220, but it's not really the same. In fact,
there, a mechanism for user-provided and generic pre-init customization
is advocated. This one can be used (and is, in the case of zypper's weak
deps) for very specific changes.

Note that, on openSUSE, the package 'parallel-printer-support' is
explicitly locked out of installation. This is because the package, when
installed, tries to creade device files (/dev/lp0, etc), which does not
work for rootless podman.

Signed-off-by: Dario Faggioli <dfaggioli@suse.com>

distrobox-create

@@ -28,6 +28,8 @@
 #	DBX_CONTAINER_MANAGER
 #	DBX_CONTAINER_NAME
 #	DBX_NON_INTERACTIVE
+# Optional container init variables:
+#	DBX_CONTAINER_INIT_ZYPPER_NORECOMMENDS
 
 trap '[ "$?" -ne 0 ] && printf "\nAn error occurred\n"' EXIT
 
@@ -505,6 +507,13 @@ generate_command() {
 	# Add additional flags
 	result_command="${result_command} ${container_manager_additional_flags}"
 
+	# Add init-time environment variables. The only requirement is that
+	# their name begins with DBX_CONTAINER_INIT_. They'll (likely!) be
+	# consumed by container-init, or ingeneral inside of the distrobox.
+	for i in $(printenv | grep '=' | grep -Ev ' |"' | grep '^DBX_CONTAINER_INIT_'); do
+		result_command="${result_command} --env \"${i}\""
+	done
+
 	# Now execute the entrypoint, refer to `distrobox-init -h` for instructions
 	result_command="${result_command} ${container_image}
 		/usr/bin/entrypoint -v --name \"${container_user_name}\"

distrobox-init

@@ -202,10 +202,15 @@ mount_bind() (
 # for users that, for instance, want to run GUI apps in their distroboxes.
 # In fact, we expect that most users would want recommended packages (which
 # are enabled by default in "regular" openSUSE/SUSE installations) in their
-# boxes, so let's re-enable them.
+# boxes, so let's re-enable them by default.
+#
+# If wanting to keep them disabled, the user can define to false the
+# DBX_INIT_ZYPPER_NO_RECOMMENDS env variable.
+[ "${DBX_CONTAINER_INIT_ZYPPER_NORECOMMENDS:-}" = "" ] && DBX_CONTAINER_INIT_ZYPPER_NORECOMMENDS=false
 if [ -f /etc/zypp/zypp.conf ]; then
-	sed -i 's/.*solver.onlyRequires.*/solver.onlyRequires = false/g' /etc/zypp/zypp.conf
+	sed -i "s/.*solver.onlyRequires.*/solver.onlyRequires = ${DBX_CONTAINER_INIT_ZYPPER_NORECOMMENDS}/g" /etc/zypp/zypp.conf
 fi
+unset DBX_CONTAINER_INIT_ZYPPER_NORECOMMENDS
 
 # Extract shell name from the $SHELL environment variable
 # If not present as package in the container, we want to install it.
@@ -418,6 +423,10 @@ if ! command -v find || ! command -v mount || ! command -v passwd ||
 			SHELL="/bin/bash"
 			shell_pkg="bash"
 		fi
+		# The 'parallel-printer-support' would try to create /dev/lpN
+		# device file, which may not work. Make sure we keep it out,
+		# as a workaround for that.
+		zypper al parallel-printer-support
 		zypper install -y \
 			"${shell_pkg}" \
 			findutils \

docs/usage/distrobox-create.md

@@ -26,6 +26,14 @@ Supported environment variables:
 	DBX_CONTAINER_NAME
 	DBX_CONTAINER_IMAGE
 
+Variables that have a name that starts with `DBX_CONTAINER_INIT_` will be added to the environment
+of the container. They are typically used for controlling some initialization time behavior, and/or
+for doing some customization of the image, suitable for being done during the init phase.
+
+Supported container-init variables:
+
+	DBX_CONTAINER_INIT_ZYPPER_NORECOMMENDS		must be either =true or =false (default)
+
 Options:
 
 	--image/-i:		image to use for the container	default: registry.fedoraproject.org/fedora-toolbox:35