rc.local

gistfile1.txt

#!/bin/bash

#---------------------------------------------------------------
#
# rc.local
#
# This script is executed at the end of each multiuser runlevel.
# Make sure that the script will "exit 0" on success or any other
# value on error.
#
# In order to enable or disable this script just change the execution
# bits.
#----------------------------------------------------------------------------
set -o nounset # exit if any variable is not set

BASE_URL="http://169.254.169.254/latest"
USERDATA_URL="${BASE_URL}/user-data"
METADATA_URL="${BASE_URL}/meta-data"
SSH_KEY_URL="${METADATA_URL}/public-keys/0/openssh-key"
USERDATA="/tmp/userdata.sh"
INIT="/root/.userdata-init"
LOG="/root/init.log"
AUTHORIZED_KEYS="/home/ec2-user/.ssh/authorized_keys"

if [ `whoami` != root ]; then
 echo "---- Please run this as the 'root' user";
 exit 1
fi

log() {
 echo $(date -R): $1 >> $LOG 2>&1
}

inject_ssh_key()
{
 # simple attempt to get the user ssh key using the meta-data service
 CURL_RESULT=$(curl -m 20 -s $SSH_KEY_URL)
 RETURN_CODE=$?
 LENGTH="${#CURL_RESULT}"
 if [ $RETURN_CODE -ne 0 ] || [ $LENGTH = 0 ]; then
   log "error retrieving ssh key"
   log "curl return code: $RETURN_CODE"
   log "curl length: $LENGTH"
 else
   KEY=$(echo $CURL_RESULT | grep 'ssh-rsa')
   grep -s -q "$KEY" "$AUTHORIZED_KEYS"
   RETURN_CODE=$?
   log " grep return code: $RETURN_CODE"
   if [ $RETURN_CODE -eq 0 ]; then
     log "ssh key found"
   else
     log "Injecting ssh key"
     mkdir -p /home/ec2-user/.ssh
     chmod 700 /home/ec2-user/.ssh
     echo $KEY >> "$AUTHORIZED_KEYS"
   fi
 fi
}

get_userdata ()
{
 wget $USERDATA_URL -O $USERDATA --append-output $LOG --no-clobber --retry-connrefused --tries=20
 RETURN_CODE=$?

 log "wget return code: $RETURN_CODE"
 if [ "$RETURN_CODE" -gt 1 ]; then
   log "error retrieving user data"
 fi

 if [ ! -f $USERDATA ]; then
   log "userdata file $USERDATA not found"
 fi

 if [ ! -s "$USERDATA" ]; then
   log "userdata file $USERDATA is zero length"
 fi
}

run_userdata()
{
 if [ ! -f $INIT ]; then
   log "running for the first time"
   RUN="true"
 else
   log "checking for run always"
   RUN=$(grep -E "^#.*CESWP_RUN_ALWAYS" $USERDATA)
 fi

 if [ -z "$RUN" ] ; then
   log "do not execute userdata"
 else
   touch $INIT
   chmod +x $USERDATA
   log "initialized on $(date -R)"
   log "-----------------------------------------------"
   log "--------------- userdata start ----------------"
   $USERDATA >> $LOG 2>&1
   log "---------------- userdata end -----------------"
   log "-----------------------------------------------"
 fi

 rm -f $USERDATA
}

log "-----------------------------------------------"
log "------ starting cloud user-data execution -----"
log "-----------------------------------------------"
inject_ssh_key
get_userdata
run_userdata
log "------ cloud user-data execution complete -----"
exit 0