#!/bin/bash

#downloads configure-linux.sh
echo "INFO: Downloading dependencies - configure-linux.sh"
curl -s -o configure-linux.sh https://www.loggly.com/install/configure-linux.sh
source configure-linux.sh "being-invoked"

##########  Variable Declarations - Start  ##########
#name of the current script
SCRIPT_NAME=configure-apache.sh
#version of the current script
SCRIPT_VERSION=1.7

#we have not found the apache version yet at this point in the script
APP_TAG="\"apache-version\":\"\""

#name of the service, in this case apache2
SERVICE=
#name of apache access log file
APACHE_ACCESS_LOG_FILE=
#name of apache error log file
APACHE_ERROR_LOG_FILE=
#name and location of apache syslog file
APACHE_SYSLOG_CONFFILE=$RSYSLOG_ETCDIR_CONF/21-apache.conf
#name and location of apache syslog backup file
APACHE_SYSLOG_CONFFILE_BACKUP=$RSYSLOG_ETCDIR_CONF/21-apache.conf.loggly.bk

#this variable will hold the path to the apache home
LOGGLY_APACHE_HOME=
#this variable will hold the value of the apache log folder
LOGGLY_APACHE_LOG_HOME=
#this variable will hold the users apache version
APACHE_VERSION=

MANUAL_CONFIG_INSTRUCTION="Manual instructions to configure Apache2 is available at https://www.loggly.com/docs/sending-apache-logs/. Rsyslog troubleshooting instructions are available at https://www.loggly.com/docs/troubleshooting-rsyslog/"

#this variable will hold if the check env function for linux is invoked
APACHE_ENV_VALIDATED="false"

#apache as tag sent with the logs
LOGGLY_FILE_TAG="apache"

#add tags to the logs
TAG=

TLS_SENDING="true"

##########  Variable Declarations - End  ##########

#check if apache environment is compatible for Loggly
checkApacheLogglyCompatibility() {
  #check if the linux environment is compatible for Loggly
  checkLinuxLogglyCompatibility

  #check if apache2 is installed on unix system
  checkApacheDetails

  APACHE_ENV_VALIDATED="true"
}

# executing the script for loggly to install and configure syslog.
installLogglyConfForApache() {
  #log message indicating starting of Loggly configuration
  logMsgToConfigSysLog "INFO" "INFO: Initiating Configure Loggly for Apache."

  #check if apache environment is compatible with Loggly
  if [ "$APACHE_ENV_VALIDATED" = "false" ]; then
    checkApacheLogglyCompatibility
  fi

  #configure loggly for Linux
  installLogglyConf

  #multiple tags
  addTagsInConfiguration

  #create 21apache.conf file
  write21ApacheConfFile

  #check for the apache log file size
  checkLogFileSize $LOGGLY_APACHE_LOG_HOME/$APACHE_ACCESS_LOG_FILE $LOGGLY_APACHE_LOG_HOME/$APACHE_ERROR_LOG_FILE

  #verify if the apache logs made it to loggly
  checkIfApacheLogsMadeToLoggly

  #log success message
  logMsgToConfigSysLog "SUCCESS" "SUCCESS: Apache successfully configured to send logs to Loggly."
}

#executing script to remove loggly configuration for Apache
removeLogglyConfForApache() {
  logMsgToConfigSysLog "INFO" "INFO: Initiating rollback."

  #check if the user has root permission to run this script
  checkIfUserHasRootPrivileges

  #check if the OS is supported by the script. If no, then exit
  checkIfSupportedOS

  #check if apache2 is installed on unix system
  checkApacheDetails

  #remove 21apache.conf file
  remove21ApacheConfFile

  logMsgToConfigSysLog "INFO" "INFO: Rollback completed."
}

#identify if apache2 is installed on your system and is available as a service
checkApacheDetails() {
  getApacheServiceName

  #verify if apache is installed as service
  if [ -f /etc/init.d/$SERVICE ]; then
    logMsgToConfigSysLog "INFO" "INFO: Apache is present as a service."
  elif [[ $(which systemctl) && $(systemctl list-unit-files $SERVICE.service | grep "$SERVICE.service") ]] &>/dev/null; then
    logMsgToConfigSysLog "INFO" "INFO: Apache is present as a service."
  else
    logMsgToConfigSysLog "ERROR" "ERROR: Apache is not configured as a service"
    exit 1
  fi

  #get the version of apache installed
  getApacheVersion

  #check if apache is supported
  checkIfSupportedApacheVersion

  #set all the required apache variables by this script
  setApacheVariables
}

#Get the apache service name on various linux flavors
getApacheServiceName() {
  #checking if the Linux is yum based or apt-get based
  YUM_BASED=$(command -v yum)
  APT_GET_BASED=$(command -v apt-get)

  if [ "$YUM_BASED" != "" ]; then
    SERVICE="httpd"
    APACHE_ACCESS_LOG_FILE="access_log"
    APACHE_ERROR_LOG_FILE="error_log"

  elif [ "$APT_GET_BASED" != "" ]; then
    SERVICE="apache2"
    APACHE_ACCESS_LOG_FILE="access.log"
    APACHE_ERROR_LOG_FILE="error.log"
  fi
}

#sets apache variables which will be used across various functions
setApacheVariables() {
  LOGGLY_APACHE_LOG_HOME=/var/log/$SERVICE
}

#gets the version of apache installed on the unix box
getApacheVersion() {
  APACHE_VERSION=$($SERVICE -v | grep "Server version: Apache")
  APACHE_VERSION=${APACHE_VERSION#*/}
  APACHE_VERSION=${APACHE_VERSION% *}
  APACHE_VERSION=$APACHE_VERSION | tr -d ' '
  APP_TAG="\"apache-version\":\"$APACHE_VERSION\""
  logMsgToConfigSysLog "INFO" "INFO: Apache version: $APACHE_VERSION"
}

#checks if the apache version is supported by this script, currently the script
#only supports apache2
checkIfSupportedApacheVersion() {
  apacheMajorVersion=${APACHE_VERSION%%.*}
  if [[ ($apacheMajorVersion -ne 2) ]]; then
    logMsgToConfigSysLog "ERROR" "ERROR: This script only supports Apache version 2."
    exit 1
  fi
}

checkLogFileSize() {
  accessFileSize=$(wc -c "$1" | cut -f 1 -d ' ')
  errorFileSize=$(wc -c "$2" | cut -f 1 -d ' ')
  fileSize=$((accessFileSize + errorFileSize))
  if [ $fileSize -ge 102400000 ]; then
    if [ "$SUPPRESS_PROMPT" == "false" ]; then
      while true; do
        read -p "WARN: There are currently large log files which may use up your allowed volume. Please rotate your logs before continuing. Would you like to continue now anyway? (yes/no)" yn
        case $yn in
        [Yy]*)
          logMsgToConfigSysLog "INFO" "INFO: Current apache logs size is $fileSize bytes. Continuing with Apache Loggly configuration."
          break
          ;;
        [Nn]*)
          logMsgToConfigSysLog "INFO" "INFO: Current apache logs size is $fileSize bytes. Discontinuing with Apache Loggly configuration."
          exit 1
          break
          ;;
        *) echo "Please answer yes or no." ;;
        esac
      done
    else
      logMsgToConfigSysLog "WARN" "WARN: There are currently large log files which may use up your allowed volume."
      logMsgToConfigSysLog "INFO" "INFO: Current apache logs size is $fileSize bytes. Continuing with Apache Loggly configuration."
    fi
  elif [ $fileSize -eq 0 ]; then
    logMsgToConfigSysLog "WARN" "WARN: There are no recent logs from Apache there so won't be any sent to Loggly. You can generate some logs by visiting a page on your web server."
    exit 1
  fi
}

write21ApacheConfFile() {
  #Create apache syslog config file if it doesn't exist
  echo "INFO: Checking if apache sysconf file $APACHE_SYSLOG_CONFFILE exist."
  if [ -f "$APACHE_SYSLOG_CONFFILE" ]; then

    logMsgToConfigSysLog "WARN" "WARN: Apache syslog file $APACHE_SYSLOG_CONFFILE already exist."
    if [ "$SUPPRESS_PROMPT" == "false" ]; then
      while true; do
        read -p "Do you wish to override $APACHE_SYSLOG_CONFFILE? (yes/no)" yn
        case $yn in
        [Yy]*)
          logMsgToConfigSysLog "INFO" "INFO: Going to back up the conf file: $APACHE_SYSLOG_CONFFILE to $APACHE_SYSLOG_CONFFILE_BACKUP"
          sudo mv -f $APACHE_SYSLOG_CONFFILE $APACHE_SYSLOG_CONFFILE_BACKUP
          write21ApacheFileContents
          break
          ;;
        [Nn]*)
          restartRsyslog
          break ;;
        *) echo "Please answer yes or no." ;;
        esac
      done
    else
      logMsgToConfigSysLog "INFO" "INFO: Going to back up the conf file: $APACHE_SYSLOG_CONFFILE to $APACHE_SYSLOG_CONFFILE_BACKUP"
      sudo mv -f $APACHE_SYSLOG_CONFFILE $APACHE_SYSLOG_CONFFILE_BACKUP
      write21ApacheFileContents
    fi
  else
    write21ApacheFileContents
  fi
}

addTagsInConfiguration() {
  #split tags by comman(,)
  IFS=, read -a array <<<"$LOGGLY_FILE_TAG"
  for i in "${array[@]}"; do
    TAG="$TAG tag=\\\"$i\\\" "
  done
}
#function to write the contents of apache syslog config file
write21ApacheFileContents() {
  logMsgToConfigSysLog "INFO" "INFO: Creating file $APACHE_SYSLOG_CONFFILE"
  sudo touch $APACHE_SYSLOG_CONFFILE
  sudo chmod o+w $APACHE_SYSLOG_CONFFILE
  commonContent="
    \$ModLoad imfile
    \$InputFilePollInterval 10 
    \$WorkDirectory $RSYSLOG_DIR
    "

  if [[ "$LINUX_DIST" == *"Ubuntu"* ]]; then
    commonContent+="\$PrivDropToGroup adm
        "
  fi

  imfileStr=$commonContent"
    
    \$ActionSendStreamDriver gtls
    \$ActionSendStreamDriverMode 1
    \$ActionSendStreamDriverAuthMode x509/name
    \$ActionSendStreamDriverPermittedPeer *.loggly.com
    
    #RsyslogGnuTLS
    \$DefaultNetstreamDriverCAFile $CA_FILE_PATH
        
    # Apache access file:
    \$InputFileName $LOGGLY_APACHE_LOG_HOME/$APACHE_ACCESS_LOG_FILE
    \$InputFileTag apache-access:
    \$InputFileStateFile stat-apache-access
    \$InputFileSeverity info
    \$InputFilePersistStateInterval 20000
    \$InputRunFileMonitor

    #Apache Error file: 
    \$InputFileName $LOGGLY_APACHE_LOG_HOME/$APACHE_ERROR_LOG_FILE
    \$InputFileTag apache-error:
    \$InputFileStateFile stat-apache-error
    \$InputFileSeverity error
    \$InputFilePersistStateInterval 20000
    \$InputRunFileMonitor

    #Add a tag for apache events
    \$template LogglyFormatApache,\"<%pri%>%protocol-version% %timestamp:::date-rfc3339% %HOSTNAME% %app-name% %procid% %msgid% [$LOGGLY_AUTH_TOKEN@41058 $TAG] %msg%\n\"
    
    if \$programname == 'apache-access' then @@logs-01.loggly.com:6514;LogglyFormatApache
    if \$programname == 'apache-access' then ~
    if \$programname == 'apache-error' then @@logs-01.loggly.com:6514;LogglyFormatApache
    if \$programname == 'apache-error' then ~
    "
  imfileStrNonTls=$commonContent"
    
    # Apache access file:
    \$InputFileName $LOGGLY_APACHE_LOG_HOME/$APACHE_ACCESS_LOG_FILE
    \$InputFileTag apache-access:
    \$InputFileStateFile stat-apache-access
    \$InputFileSeverity info
    \$InputFilePersistStateInterval 20000
    \$InputRunFileMonitor
    
    #Apache Error file: 
    \$InputFileName $LOGGLY_APACHE_LOG_HOME/$APACHE_ERROR_LOG_FILE
    \$InputFileTag apache-error:
    \$InputFileStateFile stat-apache-error
    \$InputFileSeverity error
    \$InputFilePersistStateInterval 20000
    \$InputRunFileMonitor
    
    #Add a tag for apache events
    \$template LogglyFormatApache,\"<%pri%>%protocol-version% %timestamp:::date-rfc3339% %HOSTNAME% %app-name% %procid% %msgid% [$LOGGLY_AUTH_TOKEN@41058 $TAG] %msg%\n\"
    
    if \$programname == 'apache-access' then @@logs-01.loggly.com:514;LogglyFormatApache
    if \$programname == 'apache-access' then ~
    if \$programname == 'apache-error' then @@logs-01.loggly.com:514;LogglyFormatApache
    if \$programname == 'apache-error' then ~
    "

  if [ $TLS_SENDING == "false" ]; then
    imfileStr=$imfileStrNonTls
  fi

  #change the apache-21 file to variable from above and also take the directory of the apache log file.
  sudo cat <<EOIPFW >>$APACHE_SYSLOG_CONFFILE
$imfileStr
EOIPFW

  restartRsyslog
}

#checks if the apache logs made to loggly
checkIfApacheLogsMadeToLoggly() {
  counter=1
  maxCounter=10

  apacheInitialLogCount=0
  apacheLatestLogCount=0

  TAGS=
  IFS=, read -a array <<<"$LOGGLY_FILE_TAG"
  for i in "${array[@]}"; do
    if [ "$TAGS" == "" ]; then
      TAGS="tag%3A$i"
    else
      TAGS="$TAGS%20tag%3A$i"
    fi
  done

  read -p "In order to check if Apache logs are successfully sent to Loggly, apache needs to produce logs. Do you want to create a log record by accessing server? (yes/no)" yn
  case $yn in
  [Yy]*)
    #access a page on apache server in order to create a log record in access log file
    WEB_ADDRESS=127.0.0.1
    while true; do
      read -p "Default check is performed on a localhost address 127.0.0.1 . Are you running an apache server with a different address? (yes/no)" yesno
      case $yesno in
      [Yy]*)
        logMsgToConfigSysLog "INFO" "INFO: Using specific apache server address."
        read -p "Please enter Apache server address " -r WEB_ADDRESS
        ;;
      [Nn]*)
        logMsgToConfigSysLog "INFO" "INFO: Using default apache server address."
        ;;
      *) echo "Please answer yes or no." ;;
      esac

      RESPONSE_CODE=$(curl --max-time 10 -s -o /dev/null -i -w "%{http_code}" $WEB_ADDRESS)
      #curl return 000 response on reaching max-time
      if [ ${RESPONSE_CODE} != "000" ]; then
          logMsgToConfigSysLog "INFO" "INFO: Curl on server $WEB_ADDRESS has succeeded"
        break;
      else
          logMsgToConfigSysLog "INFO" "INFO: Curl on server $WEB_ADDRESS has failed."
      fi
    done
    ;;
  [Nn]*)
    logMsgToConfigSysLog "INFO" "INFO: Creating a sample log record has been skipped."
    ;;
  *) echo "Please answer yes or no." ;;
  esac

  queryParam="$TAGS&from=-15m&until=now&size=1"
  queryUrl="$LOGGLY_ACCOUNT_URL/apiv2/search?q=$queryParam"
  logMsgToConfigSysLog "INFO" "INFO: Search URL: $queryUrl"

  logMsgToConfigSysLog "INFO" "INFO: Getting initial apache log count."
  #get the initial count of apache logs for past 15 minutes
  searchAndFetch apacheInitialLogCount "$queryUrl"

  logMsgToConfigSysLog "INFO" "INFO: Verifying if the apache logs made it to Loggly."
  logMsgToConfigSysLog "INFO" "INFO: Verification # $counter of total $maxCounter."
  #get the final count of apache logs for past 15 minutes
  searchAndFetch apacheLatestLogCount "$queryUrl"
  let counter=$counter+1

  while [ "$apacheLatestLogCount" -le "$apacheInitialLogCount" ]; do
    echo "INFO: Did not find the test log message in Loggly's search yet. Waiting for 30 secs."
    sleep 30
    echo "INFO: Done waiting. Verifying again."
    logMsgToConfigSysLog "INFO" "INFO: Verification # $counter of total $maxCounter."
    searchAndFetch apacheLatestLogCount "$queryUrl"
    let counter=$counter+1
    if [ "$counter" -gt "$maxCounter" ]; then
      logMsgToConfigSysLog "ERROR" "ERROR: Apache logs did not make to Loggly in time. Please check network and firewall settings and retry."
      exit 1
    fi
  done

  if [ "$apacheLatestLogCount" -gt "$apacheInitialLogCount" ]; then
    logMsgToConfigSysLog "INFO" "INFO: Apache logs successfully transferred to Loggly! You are now sending Apache logs to Loggly."
    checkIfLogsAreParsedInLoggly
  fi
}
#verifying if the logs are being parsed or not
checkIfLogsAreParsedInLoggly() {
  apacheInitialLogCount=0
  TAG_PARSER=
  IFS=, read -a array <<<"$LOGGLY_FILE_TAG"

  for i in "${array[@]}"; do
    TAG_PARSER="$TAG_PARSER%20tag%3A$i "
  done
  queryParam="logtype%3Aapache$TAG_PARSER&from=-15m&until=now&size=1"
  queryUrl="$LOGGLY_ACCOUNT_URL/apiv2/search?q=$queryParam"
  searchAndFetch apacheInitialLogCount "$queryUrl"
  logMsgToConfigSysLog "INFO" "INFO: Verifying if the Apache logs are parsed in Loggly."
  if [ "$apacheInitialLogCount" -gt 0 ]; then
    logMsgToConfigSysLog "INFO" "INFO: Apache logs successfully parsed in Loggly!"
  else
    logMsgToConfigSysLog "WARN" "WARN: We received your logs but they do not appear to use one of our automatically parsed formats. You can still do full text search and counts on these logs, but you won't be able to use our field explorer. Please consider switching to one of our automated formats https://www.loggly.com/docs/automated-parsing/"
  fi
}

#remove 21apache.conf file
remove21ApacheConfFile() {
  echo "INFO: Deleting the loggly apache syslog conf file."
  if [ -f "$APACHE_SYSLOG_CONFFILE" ]; then
    sudo rm -rf "$APACHE_SYSLOG_CONFFILE"
  fi
  echo "INFO: Removed all the modified files."
  restartRsyslog
}

#display usage syntax
usage() {
  cat <<EOF
usage: configure-apache [-a loggly auth account or subdomain] [-t loggly token (optional)] [-u username] [-p password (optional)] [-tag filetag1,filetag2 (optional)] [-s suppress prompts {optional)] [--insecure {to send logs without TLS} (optional)]
usage: configure-apache [-a loggly auth account or subdomain] [-r to rollback]
usage: configure-apache [-h for help]
EOF
}

##########  Get Inputs from User - Start  ##########

if [ $# -eq 0 ]; then
  usage
  exit
else
  while [ "$1" != "" ]; do
    case $1 in
    -t | --token)
      shift
      LOGGLY_AUTH_TOKEN=$1
      echo "AUTH TOKEN $LOGGLY_AUTH_TOKEN"
      ;;
    -a | --account)
      shift
      LOGGLY_ACCOUNT=$1
      echo "Loggly account or subdomain: $LOGGLY_ACCOUNT"
      ;;
    -u | --username)
      shift
      LOGGLY_USERNAME=$1
      echo "Username is set"
      ;;
    -p | --password)
      shift
      LOGGLY_PASSWORD=$1
      ;;
    -tag | --filetag)
      shift
      LOGGLY_FILE_TAG=$1
      echo "File tag: $LOGGLY_FILE_TAG"
      ;;
    -r | --rollback)
      LOGGLY_ROLLBACK="true"
      ;;
    -s | --suppress)
      SUPPRESS_PROMPT="true"
      ;;
    -h | --help)
      usage
      exit
      ;;
    --insecure)
      LOGGLY_TLS_SENDING="false"
      TLS_SENDING="false"
      LOGGLY_SYSLOG_PORT=514
      ;;
    esac
    shift
  done
fi

if [ "$LOGGLY_ACCOUNT" != "" -a "$LOGGLY_USERNAME" != "" ]; then
  if [ "$LOGGLY_PASSWORD" = "" ]; then
    getPassword
  fi
  installLogglyConfForApache
elif [ "$LOGGLY_ROLLBACK" != "" -a "$LOGGLY_ACCOUNT" != "" ]; then
  removeLogglyConfForApache
else
  usage
fi

##########  Get Inputs from User - End  ##########