Make it possible to set a size from within a flavour, and use that for devstack.

README.md

@@ -57,6 +57,16 @@ Writing a flavour
 Make as many of the following subdirectories as you need, depending on what
 part of the process you need to customise:
 
+* block-device-size.d: Alter the size (in GB) of the disk image. This is useful
+  when a particular flavour will require a certain minimum (or maximum) size.
+  You can either error and stop the build, or adjust the size to match.
+  NB: Due to the current simple implementation, the last output value wins
+  so this should be used rarely - only one flavour in a mix can reliably set
+  a size.
+
+ * outputs: $IMAGE\_SIZE={size_in_GB}
+ * inputs: $IMAGE_SIZE={size_in_GB}
+
 * block-device.d: customise the block device that the image will be made on
   (e.g. to make partitions).
 

bin/disk-image-create

@@ -46,6 +46,7 @@ ensure_nbd
 
 mk_build_dir
 ensure_base_available
+eval_run_d block-device-size "IMAGE_SIZE="
 
 qemu-img create -f qcow2 $TMP_IMAGE_PATH ${IMAGE_SIZE}G
 
@@ -60,10 +61,7 @@ fi
 sudo qemu-nbd -c $NBD_DEV $CACHE $TMP_IMAGE_PATH 
 export EXTRA_UNMOUNT="sudo qemu-nbd -d $NBD_DEV"
 export IMAGE_BLOCK_DEVICE=$NBD_DEV
-TEMP=`run_d block-device`
-echo "$TEMP"
-TEMP=`echo "$TEMP" | grep "IMAGE_BLOCK_DEVICE="`
-eval "$TEMP"
+eval_run_d block-device "IMAGE_BLOCK_DEVICE="
 
 sudo mkfs -F -t $FS_TYPE -L cloudimg-rootfs ${IMAGE_BLOCK_DEVICE}
 

docs/ci.md

@@ -16,7 +16,7 @@ Jenkins
 * Jobs to build:
  * bootstrap VM from-scratch (archive bootstrap.qcow2).
 
-        disk-image-create vm devstack -o bootstrap.qcow2 -a i386
+        disk-image-create vm devstack -o bootstrap -a i386
 
  * devstack nova-bm execution (archive the resulting image).
    Chained off of the bootstrap vm build
@@ -26,17 +26,17 @@ Jenkins
  * bootstrap VM via image-build chain (archive bm-cloud.qcow2).
 
         disk-image-create vm glance nova-bm swift mysql haproxy-api \
-        haproxy-mysql cinder quantum rabbitmq -o bootstrap-prod.qcow2
+        haproxy-mysql cinder quantum rabbitmq -o bootstrap-prod
 
  * baremetal SPOF node build (archive the resulting image).
 
         disk-image-create mysql haproxy-mysql haproxy-api local-boot \
-        rabbitmq -o baremetal-spof.qcow2
+        rabbitmq -o baremetal-spof
 
  * baremetal demo node build (archive the resulting image).
 
         disk-image-create vm glance nova-bm swift cinder quantum \
-        -o bootstrap-prod.qcow2
+        -o bootstrap-prod
 
  * ramdisk deploy image buil
 

flavours/devstack/README.md

@@ -1,2 +1,5 @@
 Creates an image prepped to make a devstack baremetal cloud. See
 demo/scripts/demo within the built image.
+
+This flavour forces a 16GB image to allow room for Swift, Cinder and instance
+disk images.

flavours/devstack/block-device-size.d/10-size

@@ -0,0 +1,9 @@
+#!/bin/bash
+# Add the stack user we recommend folk use.
+
+set -e
+set -x
+
+if (( '16' '>' $IMAGE_SIZE )); then
+   echo IMAGE_SIZE=16
+fi

lib/common-functions

@@ -34,3 +34,12 @@ function check_flavour () {
   [ -d $TMP_HOOKS_PATH ] || generate_hooks
 }
 
+# Run a hook, looking for a regex in its stdout, and eval the matched lines.
+# $1 is the hook to run
+# $2 is the regex to look for
+function eval_run_d () {
+  local TEMP=`run_d $1`
+  echo "$TEMP"
+  TEMP=`echo "$TEMP" | grep "$2"`
+  eval "$TEMP"
+}

lib/img-defaults

@@ -7,7 +7,7 @@ FS_TYPE=${FS_TYPE:-ext4}
 # Used to set the file extension only at this stage.
 IMAGE_TYPE=${IMAGE_TYPE:-qcow2}
 IMAGE_NAME=${IMAGE_NAME:-image}
-IMAGE_SIZE=${IMAGE_SIZE:-1} # N.B. This size is in GB
+export IMAGE_SIZE=${IMAGE_SIZE:-1} # N.B. This size is in GB
 # Set via the CLI normally. 
 # IMAGE_FLAVOUR=
 IMG_PATH=~/.cache/image-create