#!/bin/sh
#
# Copyright (c) 2019 AT&T Intellectual Property.
# Copyright (c) 2019 Nokia.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
#
# See the License for the specific language governing permissions and
# limitations under the License.
#
#############################
# Simple cli for xapp manager
#
# In addition to standard shell tools, requires packages "curl" and
# "yajl-tools" (the second provides json_reformat on Ubuntu; on Red Hat-style
# distributions install "yajl" instead).
#
myname=appmgrcli

usage() {
  cat <<EOF1
usage: $myname [-h host] [-p port] [-v] command params...
- command is one of deploy, undeploy, status, subscriptions, health, help
- (abbreviations dep, undep, stat, subs, heal allowed)
- Parameters of the commands that may have parameters:
-- deploy: name of the xapp to deploy
-- undeploy: name of the xapp to undeploy
-- status:
---- No parameters: Lists information about all deployed xapps
---- xapp name as parameter: Prints information about the given xapp
---- xapp name and instance: Lists information about the given instance only
-- subscriptions is followed by sub-command list, add, delete, or modify
---(abbreviations del and mod for delete and modify are allowed):
---- list without parameters lists all subscriptions
---- list with subscription id prints that subscription
---- add URL eventType maxRetry retryTimer
------- URL is the URL to notify
------- eventType one of created,deleted,all
------- maxRetry and retryTimer are positive decimal numbers
---- modify id URL eventType maxRetry retryTimer
------- id is the subscription id (find out with the list command)
--------the rest of the parameters are like in add
---- delete id
------- id is the subscription id to delete (find out with the list command)
- Default values for host and port can be set in environment
- variables APPMGR_HOST and APPMGR_PORT
- Option -v sets verbose mode.
EOF1
}

# Defaults

host=localhost
port=8080
verbose=0

# Check for environment override
if [ "x$APPMGR_HOST" != "x" ]; then
    host="$APPMGR_HOST"
fi
if [ "x$APPMGR_PORT" != "x" ]; then
    port="$APPMGR_PORT"
fi

# Proper shell option parsing:
while getopts  "h:p:v" flag
do
  # Curiously, getopts does not guard against an argument-requiring option
  # eating the next option. It also does not handle the -- convention.
  # Here is how to fix that.
  if [ "X$OPTARG" = 'X--' ]; then
    break # Explicit end of options
  fi
  if expr -- "$OPTARG" : '-.*' > /dev/null ; then
    echo $myname: Option -$flag has no required value, or value begins with -,
    echo - which is disallowed.
    usage
    exit 1
  fi
  case $flag in
  (h) host="$OPTARG"
      ;;
  (p) port="$OPTARG"
      ;;
  (v) verbose=1
      ;;
  (*)
      echo $myname: Bad option letter or required option argument missing.
      usage
      exit 1
      ;;
  esac
done
# Get rid of the option part
shift $((OPTIND-1))

if [ $verbose = 1 ]; then
  echo "host = $host"
  echo "port = $port"
fi

# Verify command

case $1 in
  (deploy|dep)
    cmd=deploy
    ;;
  (undeploy|undep)
    cmd=undeploy
    ;;
  (status|stat)
    cmd=status
    ;;
  (subscriptions|subs)
    cmd=subscriptions
    ;;
  (health|heal)
    cmd=health
    ;;
  (help)
    usage
    exit 0
    ;;
  (*)
    if [ "x$1" = "x" ]; then
     echo "$myname: Missing command"
    else
     echo "$myname: Unrecognized command $1"
    fi
    usage
    exit 1
    ;;
esac

if [ $verbose = 1 ]; then
  echo "Command $cmd params=$2"
fi

errfile=`mktemp /tmp/appmgr_e.XXXXXXXXXX`
resultfile=`mktemp /tmp/appmgr_r.XXXXXXXXXX`
# Variable status used for the return value of the whole script.
status=0

# Helper for command execution:
# Do a rest call with "curl": $1 = method, $2 = path (without host and port
# which come from variables), $3 data to POST if needed
# returns 0 if OK, and any returned data is in $resultfile
# else 1, and error message from curl is in $errfile, which is printed
# before returning the 1.
# Also sets $status to the return value.
#
# On curl options: --silent --show-error disables progress bar, but allows
# error messages. --connect-timeout 20 limits waiting for connection to
# 20 seconds. In practice connection will succeed almost immediately,
# or in the case of wrong address not at all.
#
rest() {
  local data
  if [ "x$3" != "x" ]; then
    data="--data $3"
  fi
  if curl --silent --show-error --connect-timeout 20 --header "Content-Type: application/json" -X $1 -o $resultfile "http://${host}:${port}$2" $data 2> $errfile ;then
    status=0
  else
    cat $errfile
    status=1
  fi
  return $status
}

remove_temps () {
  rm -f $errfile $resultfile
}

# Execute command ($cmd guaranteed to be valid)
# Assumes the API currently implemented.
# Functions for each command below (except health which is so simple).

base=/ric/v1
base_xapps=$base/xapps
base_health=$base/health
base_subs=$base/subscriptions

do_deploy() {
  if [ "x$1" != "x" ]; then
    if rest POST $base_xapps \{\"name\":\"$1\"\} ; then
      json_reformat < $resultfile
    fi
  else
    echo Error: expected the name of xapp to deploy
    status=1
  fi
}

do_undeploy() {
  local urlpath

  urlpath=$base_xapps
  if [ "x$1" != "x" ]; then
    urlpath="$urlpath/$1"
    if rest DELETE $urlpath; then
      # Currently xapp_manager returns an empty result if
      # undeploy is succesfull. Don't reformat file if empty.
      if [ -s $resultfile ]; then
        json_reformat < $resultfile
      else
        echo "$1 undeployed"
      fi
    fi
  else
    echo Error: expected the name of xapp to undeploy
    status=1
  fi
}

do_status() {
  local urlpath

  urlpath=$base_xapps
  if [ "x$1" != "x" ]; then
    urlpath="$urlpath/$1"
  fi
  if [ "x$2" != "x" ]; then
    urlpath="$urlpath/instances/$2"
  fi
  if rest GET $urlpath; then
    json_reformat < $resultfile
  fi
}

# This is a bit more complex. $1 is sub-command: list, add, delete, modify

# Validate the subscription data that follows a subscription add or modify
# subcommand. $1=URL, $2=eventType, $3=maxRetries, $4=retryTimer
# URL must look like URL, event type must be one of created deleted all,
# maxRetries and retryTimer must be non-negative numbers.
# If errors, sets variable status=1 and prints errors, else leaves
# status unchanged.
#
validate_subscription() {
   if ! expr "$1" : "^http://.*" \| "$1" : "^https://.*" >/dev/null; then
     echo "$myname: bad URL $1"
     status=1
   fi
   if ! [ "$2" = created -o "$2" = deleted -o "$2" = all ]; then
     echo "$myname: unrecognized event $2"
     status=1
   fi
   if ! expr "$3" : "^[0-9][0-9]*$" >/dev/null; then
     echo "$myname: invalid maximum retries count $3"
     status=1	
   fi
   if ! expr "$4" : "^[0-9][0-9]*$" >/dev/null; then
     echo "$myname: invalid retry time $4"
     status=1	
   fi
}

do_subscriptions() {
  local urlpath
  urlpath=$base_subs
  case $1 in
    (list)
      if [ "x$2" != "x" ]; then
        urlpath="$urlpath/$2"
      fi
      if rest GET $urlpath; then
        json_reformat < $resultfile
      else
        status=1
      fi
    ;;
    (add)
      validate_subscription "$2" "$3" "$4" "$5"
      if [ $status = 0 ]; then
        if rest POST $urlpath \{\"targetUrl\":\"$2\",\"eventType\":\"$3\",\"maxRetries\":$4,\"retryTimer\":$5\} ; then
          json_reformat < $resultfile
        else
          status=1
	fi
      fi
    ;;
    (delete|del)
      if [ "x$2" != "x" ]; then
        urlpath="$urlpath/$2"
      else
	echo "$myname: Subscription id required"
	status=1
      fi
      if [ $status = 0 ]; then
        if rest DELETE $urlpath; then
          # Currently xapp_manager returns an empty result if
          # delete is succesfull. Don't reformat file if empty.
          if [ -s $resultfile ]; then
            json_reformat < $resultfile
          else
            echo "Subscription $2 deleted"
          fi
        else
          status=1
	fi        
      fi
    ;;
    (modify|mod)
      if [ "x$2" != "x" ]; then
        urlpath="$urlpath/$2"
      else
	echo "$myname: Subscription id required"
	status=1
      fi
      if [ $status = 0 ]; then
        validate_subscription "$3" "$4" "$5" "$6"
        if [ $status = 0 ]; then
          if rest PUT $urlpath \{\"targetUrl\":\"$3\",\"eventType\":\"$4\",\"maxRetries\":$5,\"retryTimer\":$6\} ; then
            json_reformat < $resultfile
          else
            status=1
          fi
        fi
      fi
    ;;
    (*)
      echo "$myname: unrecognized subscriptions subcommand $1"
      status=1
  esac
}

case $cmd in
  (deploy)
    do_deploy "$2"
    ;;
  (undeploy)
    do_undeploy "$2"
    ;;
  (status)
    do_status "$2" "$3"
    ;;
  (subscriptions)
    do_subscriptions "$2" "$3" "$4" "$5" "$6" "$7"
    ;;
  (health)
    if rest GET $base_health ; then
      echo OK
    else
      echo NOT OK
    fi
    ;;
esac
remove_temps
exit $status

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