Asterisk manager Example: Bash

user@host:$ mkfifo to_script && ./check_offending_channels.sh < to_script | telnet > to_script; rm to_script

check_offending_channels.sh

#!/bin/sh
# Invoke as follows:
# mkfifo to_script && ./script.sh < to_script | telnet > to_script; rm to_script

# Some variables for customisation
SECONDS_THRESHOLD=10
ASTERISK_HOST=localhost
AMI_USER=manager
AMI_PASS=password
SUBJECT="WARNING: Channels found which are more than $SECONDS_THRESHOLD up"
EMAIL="[email protected]"
BODY=$( cat <<EOF
There is at least one channel which exceeds the offending threshold.
See attached file for details
EOF)

# Files used for logging data (will be removed)
CHANSTATUS=/tmp/channels_`date +%s`.txt
ERRORLOG=/tmp/channel_error_`date +%s`.txt

function noOp() {
        return;
}

function channelCb() {
        echo "$1" >> $CHANSTATUS
}

# Reads from asterisk, invokes a callback with the line
# and breaks as soon as a certain regular expression matches
function readResponse() {
        break=$1
        callback=$2
        while true; do
                read RESPONSE
                $callback "${RESPONSE}"
                if echo "$RESPONSE" | grep "$break"; then
                        break;
                fi
        done
}

rm $CHANSTATUS > /dev/null 2>&1
# Tell telnet to connect
echo "open $ASTERISK_HOST 5038"

# Wait for asterisk to say hello
readResponse "Asterisk Call Manager" noOp

# login to the AMI
cat <<EOF
Action: Login
ActionID: 1
Username: $AMI_USER
Secret: $AMI_PASS
Events: off

EOF

# Invoke the Status action
cat <<EOF
Action: Status
ActionID: 2

EOF

# Wait for asterisk to complete the Status action and log responses to file
readResponse "Event: StatusComplete" channelCb

cat <<EOF
Action: Logoff
ActionID: 3

EOF

# Tell telnet to quit
echo "quit"

# Function for logging offending channels
function printChannelInfo() {
        if ! [ -z $PRINTINFO ]; then
                echo "Printing $CHANNEL" >&2
                echo -e "$CHANNELINFO" >> $ERRORLOG
                echo "----------------" >> $ERRORLOG
        fi
}

rm $ERRORLOG > /dev/null 2>&1
CHANNELINFO=""
PRINTINFO=
FOUNDOFFENDINGCHANNEL=
IFS=$'\012' # Split on newline

# Read asterisk channel info
for line in `cat $CHANSTATUS`; do
        if echo "$line" | grep 'Channel: ' > /dev/null; then
                printChannelInfo
                CHANNEL=`echo $line | awk '{ print $2 }'`
                PRINTINFO=
                CHANNELINFO=
        fi
        CHANNELINFO="${CHANNELINFO}\n$line"
        sec=`echo $line | grep 'Seconds: ' | awk '{ print $2 }'`
        if ! [ -z $sec ]; then
                if [ $sec -gt $SECONDS_THRESHOLD ]; then
                        echo "Found offending channel $CHANNEL" >&2
                        PRINTINFO=yes
                        FOUNDOFFENDINGCHANNEL=yes
                fi
        fi
done
printChannelInfo

rm $CHANSTATUS > /dev/null 2>&1

# Mail offending channels if there are any
if ! [ -z $FOUNDOFFENDINGCHANNEL ]; then
        echo "Mailing error" >&2
        echo "$SUBJECT" >&2
        echo "$EMAIL" >&2
        echo "$ERRORLOG" >&2
        echo "$BODY" >&2
        # Set home for mutt
        HOME=/tmp
        mutt -f /dev/null -R -s "$SUBJECT" -a "$ERRORLOG" "$EMAIL" 1>&2 <<EOF
$BODY
EOF
fi

rm $ERRORLOG > /dev/null 2>&1
exit 0