Build an Azure agent ACI using CentOS 7 (WIP)

build.sh

#!/bin/bash -e

# Build a CentOS system with the configuration file from CoreOS.
config_url='https://raw.githubusercontent.com/coreos/coreos-overlay/master/app-emulation/wa-linux-agent/files/waagent.conf'
mirrorlist='http://mirrorlist.centos.org/?release=7&arch=x86_64&repo=os'
mirror=$(
         IFS=$'\n' urls=($(curl --location --silent "$mirrorlist"))
         echo "${urls[$((RANDOM % ${#urls[@]}))]}"
)

# Note where dependencies are actually used.
dependencies=(
        e2fsprogs net-tools openssl parted util-linux  # waagent
        bind-utils hostname  # CustomScriptForLinux
        rsyslog tar which yum  # LinuxDiagnostic
)

# Ensure there are no previously written files that get in the way.
sudo rm -fr manifest rootfs WALinuxAgent

# Install the system with all the dependencies known so far.
sudo dnf --disablerepo='*' --installroot="$PWD/rootfs" \
    --repofrompath=centos,"$mirror" --enablerepo=centos \
    -y install "${dependencies[@]}"

# Take out some directories that are not useful.
sudo rm -fr \
    rootfs/usr/lib/locale/locale-archive \
    rootfs/usr/share/{doc,info,man} \
    rootfs/var/{cache,lib}/dnf

# Fake an init system for the OMI stuff.
sudo tee rootfs/etc/init.d/functions << 'EOF' > /dev/null
daemon() { ("$@" &)& }
echo_success() { echo OK ; }
echo_failure() { echo FAILURE ; }
status() { echo "Don't care" ; }
EOF
sudo tee rootfs/usr/sbin/invoke-rc.d << 'EOF' > /dev/null
#!/bin/sh -e                                                     
[ $# -ge 2 ]           # There should be args: <service> <action>
exec /etc/init.d/"$@"
EOF
sudo chmod 0755 rootfs/usr/sbin/invoke-rc.d

# Add in the latest agent code (or checkout a specific commit first).
git clone https://github.com/Azure/WALinuxAgent.git
sudo install -pm 0755 -t rootfs/usr/bin \
    WALinuxAgent/bin/waagent \
    WALinuxAgent/bin/waagent2.0
sudo cp -rt rootfs/usr/lib/python2.7/site-packages \
    WALinuxAgent/azurelinuxagent

# Download an agent configuration file into place.
sudo curl --location --silent --output rootfs/etc/waagent.conf "$config_url"

# Update the manifest for the ACI.
sudo tee manifest << EOF > /dev/null
{
  "acKind": "ImageManifest",
  "acVersion": "0.8.6",
  "name": "coreos.com/oem-azure",
  "labels": [
    {"name": "arch", "value": "amd64"},
    {"name": "os", "value": "linux"},
    {"name": "version", "value": "7+$(date '+%Y-%m-%d-%H%M')"}
  ],
  "app": {
    "exec": ["/usr/bin/python", "-u", "/usr/bin/waagent", "-daemon"],
    "user": "0",
    "group": "0",

    "environment": [
      {
        "name": "PYTHONPATH",
        "value": "/usr/bin"
      }
    ],

    "mountPoints": [
      {
        "name": "modules",
        "path": "/lib/modules",
        "readOnly": true
      }
    ]
  }
}
EOF

# Write the ACI.
sudo tar -czf centos.aci manifest rootfs

run.sh

#!/bin/sh -e
sudo rkt --insecure-options=image run \
    --stage1-path=/usr/lib/rkt/stage1-images/stage1-fly.aci \
    --volume=modules,kind=host,source=/lib/modules,readOnly=true \
    --dns=host \
    --hosts-entry=host \
    --net=host \
    centos.aci "$@"
sudo rkt gc --grace-period=0