snap: Alternate fix for snap pre-seeding (LP: #1775710)

* Backport: Refactor functions out of ubuntu-cpc and ubuntu-server hooks.
  * Backport: Add dependency on distro-info for snap preseeding

debian/changelog

@@ -1,8 +1,8 @@
 livecd-rootfs (2.408.32) xenial; urgency=medium
 
   * snaps: Fixes for snap pre-seeding (LP: #1775710)
-  * Add dependency on distro-info for snap preseeding
+    * Backport: Refactor functions out of ubuntu-cpc and ubuntu-server hooks.
-  * Move snap-related functions to avoid conflicts with ubuntu-cpc functions
+    * Add dependency on distro-info for snap preseeding
 
  -- Robert C Jennings <robert.jennings@canonical.com>  Thu, 07 Jun 2018 14:12:26 -0700
 

live-build/auto/config

@@ -33,8 +33,10 @@ if [ -z "$MIRROR" ]; then
 	esac
 fi
 
+mkdir -p config
+cp -af /usr/share/livecd-rootfs/live-build/functions config/functions
+
 mkdir -p config/package-lists
-cp -af /usr/share/livecd-rootfs/live-build/functions.snaps config/functions.snaps
 
 add_task ()
 {

live-build/functions

@@ -1,7 +1,8 @@
 # vi: ts=4 expandtab syntax=sh
 
-CLOUD_IMG_STR="# CLOUD_IMG: This file was created/modified by the Cloud Image build process"
+#imagesize=${IMAGE_SIZE:-$((2252*1024**2))}  # 2.2G (the current size we ship)
-IMAGE_SIZE=$((2252*1024**2))  # 2.2G (the current size we ship)
+imagesize=${IMAGE_SIZE:-2361393152}  # 2.2G (the current size we ship)
+fs_label="${FS_LABEL:-rootfs}"
 
 rootfs_dev_mapper=
 loop_device=
@@ -39,13 +40,13 @@ clean_loops() {
 
 create_empty_disk_image() {
     # Prepare an empty disk image
-    dd if=/dev/zero of="$1" bs=1 count=0 seek="${IMAGE_SIZE}"
+    dd if=/dev/zero of="$1" bs=1 count=0 seek="${imagesize}"
 }
 
 make_ext4_partition() {
     device="$1"
-
+    label=${fs_label:+-L "${fs_label}"}
-    mkfs.ext4 -F -b 4096 -i 8192 -m 0 -L cloudimg-rootfs -E resize=536870912 "$device"
+    mkfs.ext4 -F -b 4096 -i 8192 -m 0 ${label} -E resize=536870912 "$device"
 }
 
 mount_image() {
@@ -56,7 +57,7 @@ mount_image() {
 
     # Find the loop device
     loop_p1="$(echo -e ${kpartx_mapping} | head -n1 | awk '{print$3}')"
-    loop_device="/dev/loop$(echo ${loop_p1} | cut -b5)"
+    loop_device="/dev/${loop_p1%p[0-9]*}"
     if [ ! -b ${loop_device} ]; then
         echo "unable to find loop device for ${backing_img}"
         exit 1
@@ -129,7 +130,7 @@ mount_disk_image() {
     # such as updating grub and installing software
     cat > $mountpoint/usr/sbin/policy-rc.d << EOF
 #!/bin/sh
-# ${CLOUD_IMG_STR}
+# ${IMAGE_STR}
 echo "All runlevel operations denied by policy" >&2
 exit 101
 EOF
@@ -264,7 +265,7 @@ convert_to_qcow2() {
 
 replace_grub_root_with_label() {
     # When update-grub is run, it will detect the disks in the build system.
-    # Instead, we want grub to use the cloudimg-rootfs labelled disk
+    # Instead, we want grub to use the right labelled disk
     CHROOT_ROOT="$1"
 
     # If boot by partuuid has been requested, don't override.
@@ -273,7 +274,7 @@ replace_grub_root_with_label() {
     then
         return 0
     fi
-    sed -i -e "s,root=[^ ]*,root=LABEL=cloudimg-rootfs," \
+    sed -i -e "s,root=[^ ]*,root=LABEL=${fs_label}," \
         "$CHROOT_ROOT/boot/grub/grub.cfg"
 }
 
@@ -318,3 +319,125 @@ undivert_grub() {
 	chroot "$CHROOT_ROOT" dpkg-divert --remove --local \
 		--rename /usr/bin/systemd-detect-virt
 }
+
+release_ver() {
+    # Return the release version number
+    distro-info --series="$LB_DISTRIBUTION" -r | awk '{ print $1 }'
+}
+
+_snap_preseed() {
+    # Download the snap/assertion and add to the preseed
+    local CHROOT_ROOT=$1
+    local SNAP=$2
+    local SNAP_NAME=${SNAP%/*}
+    local CHANNEL=${3:?Snap channel must be specified}
+
+    local seed_dir="$CHROOT_ROOT/var/lib/snapd/seed"
+    local snaps_dir="$seed_dir/snaps"
+    local seed_yaml="$seed_dir/seed.yaml"
+    local assertions_dir="$seed_dir/assertions"
+
+    # Download the snap & assertion
+    local snap_download_failed=0
+    chroot $CHROOT_ROOT sh -c "
+        set -x;
+        cd /var/lib/snapd/seed;
+        SNAPPY_STORE_NO_CDN=1 snap download \
+            --channel=$CHANNEL \"$SNAP_NAME\"" || snap_download_failed=1
+    if [ $snap_download_failed = 1 ] ; then
+        echo "If the channel ($CHANNEL) includes '*/ubuntu-##.##' track per "
+        echo "Ubuntu policy (ex. stable/ubuntu-18.04) the publisher will need "
+        echo "to temporarily create the channel/track to allow fallback during"
+        echo "download (ex. stable/ubuntu-18.04 falls back to stable if the"
+        echo "prior had been created in the past)."
+        exit 1
+    fi
+
+    mv -v $seed_dir/*.assert $assertions_dir
+    mv -v $seed_dir/*.snap $snaps_dir
+
+    # Add the snap to the seed.yaml
+    ! [ -e $seed_yaml ] && echo "snaps:" > $seed_yaml
+    cat <<EOF >> $seed_yaml
+  -
+    name: ${SNAP_NAME}
+    channel: ${CHANNEL}
+EOF
+
+    case ${SNAP} in */classic) echo "    classic: true" >> $seed_yaml;; esac
+
+    echo -n "    file: " >> $seed_yaml
+    (cd $snaps_dir; ls -1 ${SNAP_NAME}_*.snap) >> $seed_yaml
+}
+
+snap_prepare_assertions() {
+    # Configure basic snapd assertions
+    local CHROOT_ROOT=$1
+    # A colon-separated string of brand:model to be used for the image's model
+    # assertion
+    local CUSTOM_BRAND_MODEL=$2
+
+    local seed_dir="$CHROOT_ROOT/var/lib/snapd/seed"
+    local snaps_dir="$seed_dir/snaps"
+    local assertions_dir="$seed_dir/assertions"
+    local model_assertion="$assertions_dir/model"
+    local account_key_assertion="$assertions_dir/account-key"
+    local account_assertion="$assertions_dir/account"
+
+    mkdir -p "$assertions_dir"
+    mkdir -p "$snaps_dir"
+
+    local brand="$(echo $CUSTOM_BRAND_MODEL | cut -d: -f 1)"
+    local model="$(echo $CUSTOM_BRAND_MODEL | cut -d: -f 2)"
+
+    if ! [ -e "$model_assertion" ] ; then
+        snap known --remote model series=16 \
+            model=$model brand-id=$brand \
+            > "$model_assertion"
+    fi
+
+    if ! [ -e "$account_key_assertion" ] ; then
+        local account_key=$(sed -n -e's/sign-key-sha3-384: //p' \
+            < "$model_assertion")
+        snap known --remote account-key \
+            public-key-sha3-384="$account_key" \
+            > "$account_key_assertion"
+    fi
+
+
+    if ! [ -e "$account_assertion" ] ; then
+        local account=$(sed -n -e's/account-id: //p' < "$account_key_assertion")
+        snap known --remote account account-id=$account \
+            > "$account_assertion"
+    fi
+}
+
+snap_prepare() {
+    # Configure basic snapd assertions and pre-seeds the 'core' snap
+    local CHROOT_ROOT=$1
+    # Optional. If set, should be a colon-separated string of brand:model to be
+    # used for the image's model assertion
+    local CUSTOM_BRAND_MODEL=${2:-generic:generic-classic}
+
+    local seed_dir="$CHROOT_ROOT/var/lib/snapd/seed"
+    local snaps_dir="$seed_dir/snaps"
+
+    snap_prepare_assertions "$CHROOT_ROOT" "$CUSTOM_BRAND_MODEL"
+
+    # Download the core snap
+    if ! [ -f $snaps_dir/core_[0-9]*.snap ] ; then
+        _snap_preseed $CHROOT_ROOT core stable
+    fi
+}
+
+snap_preseed() {
+    # Preseed a snap in the image
+    local CHROOT_ROOT=$1
+    local SNAP=$2
+    # Per Ubuntu policy, all seeded snaps (with the exception of the core
+    # snap) must pull from stable/ubuntu-$(release_ver) as their channel.
+    local CHANNEL=${3:-"stable/ubuntu-$(release_ver)"}
+
+    snap_prepare $CHROOT_ROOT
+    _snap_preseed $CHROOT_ROOT $SNAP $CHANNEL
+}

live-build/functions.snaps

@@ -1,126 +0,0 @@
-# vi: ts=4 expandtab syntax=sh
-
-#imagesize=${IMAGE_SIZE:-$((2252*1024**2))}  # 2.2G (the current size we ship)
-imagesize=${IMAGE_SIZE:-2361393152}  # 2.2G (the current size we ship)
-
-release_ver() {
-    # Return the release version number
-    distro-info --series="$LB_DISTRIBUTION" -r | awk '{ print $1 }'
-}
-
-_snap_preseed() {
-    # Download the snap/assertion and add to the preseed
-    local CHROOT_ROOT=$1
-    local SNAP=$2
-    local SNAP_NAME=${SNAP%/*}
-    local CHANNEL=${3:?Snap channel must be specified}
-
-    local seed_dir="$CHROOT_ROOT/var/lib/snapd/seed"
-    local snaps_dir="$seed_dir/snaps"
-    local seed_yaml="$seed_dir/seed.yaml"
-    local assertions_dir="$seed_dir/assertions"
-
-    # Download the snap & assertion
-    local snap_download_failed=0
-    chroot $CHROOT_ROOT sh -c "
-        set -x;
-        cd /var/lib/snapd/seed;
-        SNAPPY_STORE_NO_CDN=1 snap download \
-            --channel=$CHANNEL \"$SNAP_NAME\"" || snap_download_failed=1
-    if [ $snap_download_failed = 1 ] ; then
-        echo "If the channel ($CHANNEL) includes '*/ubuntu-##.##' track per "
-        echo "Ubuntu policy (ex. stable/ubuntu-18.04) the publisher will need "
-        echo "to temporarily create the channel/track to allow fallback during"
-        echo "download (ex. stable/ubuntu-18.04 falls back to stable if the"
-        echo "prior had been created in the past)."
-        exit 1
-    fi
-
-    mv -v $seed_dir/*.assert $assertions_dir
-    mv -v $seed_dir/*.snap $snaps_dir
-
-    # Add the snap to the seed.yaml
-    ! [ -e $seed_yaml ] && echo "snaps:" > $seed_yaml
-    cat <<EOF >> $seed_yaml
-  -
-    name: ${SNAP_NAME}
-    channel: ${CHANNEL}
-EOF
-
-    case ${SNAP} in */classic) echo "    classic: true" >> $seed_yaml;; esac
-
-    echo -n "    file: " >> $seed_yaml
-    (cd $snaps_dir; ls -1 ${SNAP_NAME}_*.snap) >> $seed_yaml
-}
-
-snap_prepare_assertions() {
-    # Configure basic snapd assertions
-    local CHROOT_ROOT=$1
-    # A colon-separated string of brand:model to be used for the image's model
-    # assertion
-    local CUSTOM_BRAND_MODEL=$2
-
-    local seed_dir="$CHROOT_ROOT/var/lib/snapd/seed"
-    local snaps_dir="$seed_dir/snaps"
-    local assertions_dir="$seed_dir/assertions"
-    local model_assertion="$assertions_dir/model"
-    local account_key_assertion="$assertions_dir/account-key"
-    local account_assertion="$assertions_dir/account"
-
-    mkdir -p "$assertions_dir"
-    mkdir -p "$snaps_dir"
-
-    local brand="$(echo $CUSTOM_BRAND_MODEL | cut -d: -f 1)"
-    local model="$(echo $CUSTOM_BRAND_MODEL | cut -d: -f 2)"
-
-    if ! [ -e "$model_assertion" ] ; then
-        snap known --remote model series=16 \
-            model=$model brand-id=$brand \
-            > "$model_assertion"
-    fi
-
-    if ! [ -e "$account_key_assertion" ] ; then
-        local account_key=$(sed -n -e's/sign-key-sha3-384: //p' \
-            < "$model_assertion")
-        snap known --remote account-key \
-            public-key-sha3-384="$account_key" \
-            > "$account_key_assertion"
-    fi
-
-
-    if ! [ -e "$account_assertion" ] ; then
-        local account=$(sed -n -e's/account-id: //p' < "$account_key_assertion")
-        snap known --remote account account-id=$account \
-            > "$account_assertion"
-    fi
-}
-
-snap_prepare() {
-    # Configure basic snapd assertions and pre-seeds the 'core' snap
-    local CHROOT_ROOT=$1
-    # Optional. If set, should be a colon-separated string of brand:model to be
-    # used for the image's model assertion
-    local CUSTOM_BRAND_MODEL=${2:-generic:generic-classic}
-
-    local seed_dir="$CHROOT_ROOT/var/lib/snapd/seed"
-    local snaps_dir="$seed_dir/snaps"
-
-    snap_prepare_assertions "$CHROOT_ROOT" "$CUSTOM_BRAND_MODEL"
-
-    # Download the core snap
-    if ! [ -f $snaps_dir/core_[0-9]*.snap ] ; then
-        _snap_preseed $CHROOT_ROOT core stable
-    fi
-}
-
-snap_preseed() {
-    # Preseed a snap in the image
-    local CHROOT_ROOT=$1
-    local SNAP=$2
-    # Per Ubuntu policy, all seeded snaps (with the exception of the core
-    # snap) must pull from stable/ubuntu-$(release_ver) as their channel.
-    local CHANNEL=${3:-"stable/ubuntu-$(release_ver)"}
-
-    snap_prepare $CHROOT_ROOT
-    _snap_preseed $CHROOT_ROOT $SNAP $CHANNEL
-}

live-build/ubuntu-cpc/hooks/032-disk-image.binary

@@ -1,9 +1,12 @@
 #!/bin/bash -ex
 
-. config/functions
+IMAGE_STR="# CLOUD_IMG: This file was created/modified by the Cloud Image build process"
+FS_LABEL="cloudimg-rootfs"
 
 . config/binary
 
+. config/functions
+
 BOOTPART_START=
 BOOTPART_END=
 BOOT_MOUNTPOINT=

live-build/ubuntu-cpc/hooks/033-disk-image-uefi.binary

@@ -9,6 +9,11 @@ case $ARCH in
         ;;
 esac
 
+IMAGE_STR="# CLOUD_IMG: This file was created/modified by the Cloud Image build process"
+FS_LABEL="cloudimg-rootfs"
+
+. config/binary
+
 . config/functions
 
 create_partitions() {
@@ -88,7 +93,7 @@ install_grub() {
     esac
 
     cat << EOF >> mountpoint/etc/default/grub.d/50-cloudimg-settings.cfg
-${CLOUD_IMG_STR}
+${IMAGE_STR}
 # For Cloud Image compatability
 GRUB_PRELOAD_MODULES="${GRUB_PRELOAD_MODULES:-$grub_modules}"
 EOF
@@ -104,7 +109,7 @@ EOF
 
     if [ -f mountpoint/boot/efi/EFI/BOOT/grub.cfg ]; then
         sed -i "s| root| root hd0,gpt1|" mountpoint/boot/efi/EFI/BOOT/grub.cfg
-        sed -i "1i${CLOUD_IMG_STR}" mountpoint/boot/efi/EFI/BOOT/grub.cfg
+        sed -i "1i${IMAGE_STR}" mountpoint/boot/efi/EFI/BOOT/grub.cfg
         # For some reason the grub disk is looking for /boot/grub/grub.cfg on
         # part 15....
         chroot mountpoint mkdir -p /boot/efi/boot/grub

live-build/ubuntu-cpc/hooks/034-disk-image-ppc64el.binary

@@ -7,6 +7,11 @@ case $ARCH in
         ;;
 esac
 
+IMAGE_STR="# CLOUD_IMG: This file was created/modified by the Cloud Image build process"
+FS_LABEL="cloudimg-rootfs"
+
+. config/binary
+
 . config/functions
 
 create_partitions() {
@@ -32,7 +37,7 @@ install_grub() {
     # set the kernel commandline to use hvc0
     mkdir -p mountpoint/etc/default/grub.d
     cat << EOF > mountpoint/etc/default/grub.d/50-cloudimg-settings.cfg
-${CLOUD_IMG_STR}
+${IMAGE_STR}
 
 # Set the recordfail timeout
 GRUB_RECORDFAIL_TIMEOUT=0

live-build/ubuntu-cpc/hooks/042-vagrant.binary

@@ -44,6 +44,8 @@ case $ARCH in
            exit 0;;
 esac
 
+IMAGE_STR="# CLOUD_IMG: This file was created/modified by the Cloud Image build process"
+
 . config/functions
 
 # Lets be safe about this

live-build/ubuntu-cpc/hooks/999-cpc-fixes.chroot

@@ -47,7 +47,7 @@ respawn
 script
     exec /sbin/getty -L CONDEV 115200 vt102
 end script
-${CLOUD_IMG_STR}
+${IMAGE_STR}
 EOF
    sed -i "s/CONDEV/${condev}/g" "$idir/${condev}.conf"
 }

live-build/ubuntu-cpc/hooks/999-extras.binary

@@ -8,6 +8,10 @@ if [ ! -d ${my_dir}/extra ]; then
     exit 0
 fi
 
+export IMAGE_STR="# CLOUD_IMG: This file was created/modified by the Cloud Image build process"
+export CLOUD_IMG_STR="$IMAGE_STR"
+export FS_LABEL="cloudimg-rootfs"
+
 # Export the common functions to the extras
 . config/functions