summaryrefslogtreecommitdiffstats
path: root/tools/yardstick-img-modify
blob: 5e9b450295601d1f43b93ea7153d726ff4b5eb10 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
#!/bin/bash

##############################################################################
# Copyright (c) 2015 Ericsson AB and others.
#
# All rights reserved. This program and the accompanying materials
# are made available under the terms of the Apache License, Version 2.0
# which accompanies this distribution, and is available at
# http://www.apache.org/licenses/LICENSE-2.0
##############################################################################

# yardstick-img-modify - download and modify a Ubuntu cloud image
#
# The actual customization is done by a script passed with an absolute path as
# the only single argument. The command needs to be invoked as sudo
#
# Example invocation:
# yardstick-img-modify /home/yardstick/tools/ubuntu-server-cloudimg-modify.sh
#
# Warning: the script will create files by default in:
#   /tmp/workspace/yardstick
# the files will be owned by root!
#
# TODO: image resize is needed if the base image is too small
#

set -e
set -x

die() {
    echo "error: $1" >&2
    exit 1
}

test $# -eq 1 || die "no image specific script as argument"
test $(id -u) -eq 0 || die "should invoke using sudo"

cmd=$1
test -x $cmd
mountdir="/mnt/yardstick"

workspace=${WORKSPACE:-"/tmp/workspace/yardstick"}
host=${HOST:-"cloud-images.ubuntu.com"}
release=${RELEASE:-"trusty"}
image_path="${release}/current/${release}-server-cloudimg-amd64-disk1.img"
image_url=${IMAGE_URL:-"https://${host}/${image_path}"}
md5sums_path="${release}/current/MD5SUMS"
md5sums_url=${MD5SUMS_URL:-"https://${host}/${md5sums_path}"}

imgfile="${workspace}/yardstick-${release}-server.img"
raw_imgfile="${workspace}/yardstick-${release}-server.raw"
filename=$(basename $image_url)

# download and checksum base image, conditionally if local copy is outdated
download() {
    test -d $workspace || mkdir -p $workspace
    cd $workspace
    rm -f MD5SUMS # always download the checksum file to a detect stale image
    wget $md5sums_url
    test -e $filename || wget -nc $image_url
    grep $filename MD5SUMS | md5sum -c ||
    if [ $? -ne 0 ]; then
        rm $filename
        wget -nc $image_url
        grep $filename MD5SUMS | md5sum -c
    fi
    qemu-img convert $filename $raw_imgfile
    cd -
}

# mount image
setup() {
    mkdir -p $mountdir

    for i in $(seq 0 9); do
        [ -a /dev/loop$i ] || mknod -m 660 /dev/loop$i b 7 $i
    done

    loopdevice=$(kpartx -l $raw_imgfile | head -1 | cut -f1 -d ' ')

    kpartx -a $raw_imgfile

    mount /dev/mapper/$loopdevice $mountdir
    mount -t proc none $mountdir/proc

    cp $cmd $mountdir/$(basename $cmd)
}

# modify image running a script using in a chrooted environment
modify() {
    # resolv.conf does not exist in base image, pass nameserver value from host
    nameserver_ip=$(grep -m 1 '^nameserver' \
        /etc/resolv.conf | awk '{ print $2 '})

    # prevent init scripts from running during install
    echo $'#!/bin/sh\nexit 101' >$mountdir/usr/sbin/policy-rc.d
    chmod a+x $mountdir/usr/sbin/policy-rc.d

    chroot $mountdir /$(basename $cmd) $nameserver_ip

    rm -rf $mountdir/usr/sbin/policy-rc.d

    umount -f $mountdir/proc
    umount $mountdir

    qemu-img convert -c -o compat=0.10 -O qcow2 $raw_imgfile $imgfile

    if dmsetup table | grep $loopdevice; then
       dmsetup clear $loopdevice || true
    fi
}

# cleanup (umount) the image
cleanup() {
    # designed to be idempotent
    mount | grep $mountdir/proc && umount $mountdir/proc
    mount | grep $mountdir && umount $mountdir
    if [ -f $raw_imgfile ]; then
        kpartx -dv $raw_imgfile || true
    fi
    rm -f $raw_imgfile
    rm -rf $mountdir
}

exitcode=""
error_trap()
{
    local rc=$?

    set +e

    if [ -z "$exitcode" ]; then
        exitcode=$rc
    fi

    cleanup

    echo "Image build failed with $exitcode"

    exit $exitcode
}

main() {
    cleanup

    trap "error_trap" EXIT SIGTERM

    download
    setup
    modify

    trap - EXIT SIGTERM
    cleanup

    echo "the modified image is found here: $imgfile"
}

main