logentries-downloader

#!/bin/bash

# ****************************************************************************
#           .:: LogEntries Downloader ::.
#
#   Author: Sylvain Mauduit (@Swop)
#   Company: Simple IT - http://www.simple-it.fr
#
#   Usage:
#   $ logentries-downloader (-s star_date -e end_date | -y) 
#           [-a logentries_account_key]
#           [-l logentries_log_address]
#           [-f filter]
#           [-c count]
#           [-q]
#
#   Logentries account key and log address can be set with options parameters or
#   with LOGENTRIES_ACCOUNT_KEY and LOGENTRIES_LOG_ADDR environment variables.
# ****************************************************************************

# Check if dependencies are installed
DEPENDANCIES="curl mktemp readlink"
for DEPT in $DEPENDANCIES; do
  command -v $DEPT >/dev/null 2>&1 || { echo "'$DEPT' is required but it's not installed. Aborting." >&2; exit 1; }
done

SCRIPT_PATH=$(dirname `readlink -m "$0"`)
SCRIPT_VERSION=0.1

# Import configuration from config file if present
test -f ${SCRIPT_PATH}/config && . ${SCRIPT_PATH}/config

# Override config if env variables are set
if [ -n "$LOGENTRIES_ACCOUNT_KEY" ]; then ACCOUNT_KEY=$LOGENTRIES_ACCOUNT_KEY; fi
if [ -n "$LOGENTRIES_LOG_ADDR" ]; then LOG_ADDR=$LOGENTRIES_LOG_ADDR; fi

# Print header
function header()
{
    echo "-- LogEntries Downloader $SCRIPT_VERSION - Sylvain MAUDUIT (@Swop) --"
}

# Print program usage
function usage()
{
header
cat << EOF

usage: $0 options

Download logs from Logentries.

OPTIONS:
   -h               Show this message
   -s timestamp     Start date (in seconds since epoch)
   -e timestamp     End date (in seconds since epoch)
   -y               Get yesterday logs (replace -s & -e options)
   -a account_key   [Optional] Logentries account key
   -l log_addr      [Optional] Logentries log address
   -f filter        [Optional] Filter to use
   -c count         [Optional] Maximal number of events downloaded
   -q               [Optional] Quiet mode: Do not display anything 
                    other than errors

Logentries account key and log address can be set with options parameters or
with LOGENTRIES_ACCOUNT_KEY and LOGENTRIES_LOG_ADDR environment variables.

EOF
}

function log()
{
    echo "`date --iso-860=seconds` $1"
}

function logerr()
{
    echo "`date --iso-860=seconds` $1" >&2
}

# Parse agruments
QUIET_MODE=false
FILTER=
COUNT=
YESTERDAY_MODE=false
while getopts “hs:e:ya:l:f:c:q” OPTION
do
    case $OPTION in
        h)
            usage
            exit 0
            ;;
        s)
            # If yesterday mode is enabled, skip the date configuration
            if $YESTERDAY_MODE; then
                continue
            fi

            # Check validity of param
            if [[ $OPTARG != +([0-9]) ]]; then
                usage
                exit 1
            fi

            START_TIME=$[$OPTARG * 1000]
            ;;
        e)
            # If yesterday mode is enabled, skip the date configuration
            if $YESTERDAY_MODE; then
                continue
            fi

            # Check validity of param
            if [[ $OPTARG != +([0-9]) ]]; then
                usage
                exit 1
            fi

            END_TIME=$[$OPTARG * 1000]
            ;;
        y)
            YESTERDAY_MODE=true
            
            # Generate start and end time based on yesterday timestamp
            START_TIME=$[$(date --utc -d "`date +%D` -1day" +%s) * 1000]
            END_TIME=$[$(date --utc -d "`date +%D`" +%s) * 1000]
            ;;
        a)
            ACCOUNT_KEY=$OPTARG
            ;;
        l)
            LOG_ADDR=$OPTARG
            ;;
        f)
            FILTER=$OPTARG
            ;;
        c)
            # Check validity of param
            if [[ $OPTARG != +([0-9]) ]]; then
                usage
                exit 1
            fi

            COUNT=$OPTARG
            ;;
        q)
            QUIET_MODE=true
            ;;
        ?)
            usage
            exit 1
            ;;
    esac
done

# Check if all required configurations are present
if [[ -z $START_TIME ]]                 \
    || [[ -z $END_TIME ]]               \
    || [[ -z $ACCOUNT_KEY ]]            \
    || [[ -z $LOG_ADDR ]]
then
    usage
    exit 1
fi

# Genereate temporary folder to store response file
TMP_DIR=$(mktemp -d /tmp/logentries-downloader-XXXXXX)

# Construct cURL command
CURL_COMMAND="curl -G -sL -w %{http_code} -o ${TMP_DIR}/response.log \
https://api.logentries.com/${ACCOUNT_KEY}/${LOG_ADDR}/ \
-d start=${START_TIME} -d end=${END_TIME}"

if [[ -n $FILTER ]]; then
    CURL_COMMAND="$CURL_COMMAND -d filter=${FILTER}"
fi

if [[ -n $COUNT ]]; then
    CURL_COMMAND="$CURL_COMMAND -d limit=${COUNT}"
fi

# ---- Start ----
[[ $QUIET_MODE == false ]] && header
[[ $QUIET_MODE == false ]] && log "Used cURL command: $CURL_COMMAND"

response_code=`$CURL_COMMAND`

# If someting goes wrong, display the response body in stderr
if [[ "$response_code" != "200" ]]; then
    logerr "ERROR: Something went wrong (response code: $response_code). \
Response body:"

    cat ${TMP_DIR}/response.log >&2
    RETVAL=1
else
    [[ $QUIET_MODE == false ]] && log "Logs dowloaded with success"
    cat ${TMP_DIR}/response.log
    RETVAL=0
fi

# Delete temp dir
rm -rf ${TMP_DIR}

exit $RETVAL