#!/bin/bash
# Opensearch 1.x Engine via Docker
#
# SwITNet Ltd © - 2023, https://switnet.net/
# T&M Hansson IT AB © - 2022, https://www.hanssonit.se/
# GPLv3 or later.
#

# Reset
Color_Off='\e[0m'       # Text Reset
# Regular Colors
Black='\e[0;30m'        # Black
Red='\e[0;31m'          # Red
Green='\e[0;32m'        # Green
Yellow='\e[0;33m'       # Yellow
Blue='\e[0;34m'         # Blue
Purple='\e[0;35m'       # Purple
Cyan='\e[0;36m'         # Cyan

MEM_AVAILABLE="$(grep MemTotal /proc/meminfo| grep -o '[0-9]\+')"
OPNSDIR="/opt/opensearch"
INDEX_USER="$(tr -dc '[:lower:]' < /dev/urandom | fold -w 24 | head -n1)"
OPNSREST="$(tr -dc "a-zA-Z0-9" < /dev/urandom | fold -w 32 | head -n1)"
PUBLIC_IP="$(dig -4 +short myip.opendns.com @resolver1.opendns.com)"
opens_fts="opensearchproject/opensearch:1"
fts_node="fts_os-node"
max_map_count="512000"
NL="$(printf '\n  ')"

printwc() {
    printf "%b$2%b" "$1" "${Color_Off}"
}
install_if_not() {
    if [ "$(dpkg-query -W -f='${Status}' "$1" 2>/dev/null | \
        grep -c "ok installed")" == "1" ]; then
        echo " $1 is installed, skipping..."
    else
        printf "\n---- Installing %s ----\n" "$1"
        apt-get -yq2 install "$1"
    fi
}
docker-compose_down() {
if [ -f "$1" ]
then
    cd "$(dirname "$1")"
    docker-compose down  --volume --rmi all
else
    echo "Non-existing docker-compose file path, skipping..."
fi
}
set_once_hash_comment() {
if ! awk '!/^ *#/ && NF {print}' "$2"| \
   grep -q "$(awk -F '=' '{print$1}' <<< "$1")" ; then
   echo "Setting $1 on $2..."
   echo "$1" | tee -a "$2"
else
  printf "%s\"$(awk -F '=' '{print$1}' <<< "$1")\"" "\n"
  printf " seems already present, skipping setting this variable\n"
fi
}
dig_dns_ip() {
    dig -4 +short "$1"||awk -v RS='([0-9]+\\.){3}[0-9]+' 'RT{print RT}'
}
create_certs() {
    cp static/opensearch_certs.sh "$OPNSDIR"
    sed -i "s|__FTSDOMAIN__|$1|" "$OPNSDIR"/opensearch_certs.sh
    cd "$OPNSDIR"
    bash opensearch_certs.sh
    rm -f "$OPNSDIR"/opensearch_certs.sh
}
countdown() {
printwc "$Cyan" "$1"
secs="$(($2))"
while [ $secs -gt 0 ]; do
   echo -ne "$secs\033[0K\r"
   sleep 1
   : $((secs--))
done
}

#Check if user is root
if ! [ "$(id -u)" = 0 ]; then
   echo "You need to be root or have sudo privileges!"
   exit 0
fi

# Check update
apt-get update -q2

# Test RAM size (4GB min) + CPUs (min 2)
#Check system resources
printf "\n\nVerifying System Resources:"
if [ "$(nproc --all)" -lt 2 ];then
    printf "\nWarning!: The system do not meet the minimum CPU"
    printf " requirements for Opensearch to run."
    printf "\n>> We recommend 2 cores/threads for Opensearch!\n"
    CPU_MIN="N"
else
    printf "\nCPU Cores/Threads: OK (%s)\n" "$(nproc --all)"
    CPU_MIN="Y"
fi
sleep .1
### Test RAM size (4GB min) ###
if [ "$MEM_AVAILABLE" -lt 3700000 ]; then
    printf "\nWarning!: The system do not meet the minimum RAM"
    printf " requirements for Jibri to run."
    printf "\n>> We recommend at least 4GB RAM for Opensearch!\n\n"
    MEM_MIN="N"
else
    printf "\nMemory: OK (%s) MiB\n\n" "$((MEM_AVAILABLE/1024))"
    MEM_MIN="Y"
fi
sleep .1
if [ "$CPU_MIN" = "Y" ] && [ "$MEM_MIN" = "Y" ];then
    echo "All requirements seems meet!"
else
    printf "CPU (%s)/RAM (%s MiB)" "$(nproc --all)" "$((MEM_AVAILABLE/1024))"
    printf " does NOT meet minimum recommended requirements!"
sleep .1
    while [ "$CONTINUE_LR" != "yes" ] && [ "$CONTINUE_LR" != "no" ]
    do
    read -p "> Do you want to continue?: (yes or no)$NL" -r CONTINUE_LR
    if [ "$CONTINUE_LR" = "no" ]; then
            printf "\n - See you next time with more resources!..."
            exit
    elif [ "$CONTINUE_LR" = "yes" ]; then
            printf "\n - We highly recommend to increase the server resources."
    fi
    done
fi
sleep .1
if [ "$CONTINUE_LR" = "yes" ]; then
printf '\nThis server will likely have issues due the lack of resources.\n'
printf '>>> We highly recommend to increase resources of this server. <<<\n'
fi
sleep .1
# Set domain
while [ "$ANS_DMN" != "yes" ]
do
    read -p "> Set your CA domain (or subdomain) here: $NL" -r DOMAIN
    read -p "  > Did you mean?: $DOMAIN (yes or no)$NL" -r ANS_DMN
    if [ "$ANS_DMN" = "yes" ]
    then
        echo "   - Alright, let's use $DOMAIN."
    else
        echo "   - Please try again."
    fi
done
sleep .1
# Simple DNS test
if [ "$PUBLIC_IP" = "$(dig_dns_ip "$DOMAIN")" ]; then
    printf "\nServer public IP  & DNS record for"
    printf " %s seems to match, continuing..." "$DOMAIN"
else
    echo -n "Server public IP ($PUBLIC_IP) & DNS record for $DOMAIN"
    echo " don't seem to match."
    echo -n "  > Please check your dns records are applied and updated,"
    echo " otherwise components may fail."
    read -p "  > Do you want to continue?: (yes or no)$NL" -r DNS_CONTINUE
    if [ "$DNS_CONTINUE" = "yes" ]; then
        echo "  - We'll continue anyway..."
    else
        echo "  - Exiting for now..."
        exit
    fi
fi
sleep .1
# Check & install docker
install_if_not docker.io
install_if_not docker-compose

sysctl -w vm.max_map_count="$max_map_count"
set_once_hash_comment "vm.max_map_count=$max_map_count" "/etc/sysctl.conf"

mkdir -p "$OPNSDIR"
docker pull "$opens_fts"
BCRYPT_HASH="$(docker run --rm -it $opens_fts \
               bash -c "plugins/opensearch-security/tools/hash.sh \
               -p $OPNSREST | tr -d ':\n' ")"

# Create configurations YML
# opensearch.yml
cat << YML_OPENSEARCH > $OPNSDIR/opensearch.yml
cluster.name: docker-cluster
# Avoid Docker assigning IP.
network.host: 0.0.0.0

# Declaring single node cluster.
discovery.type: single-node

######## Start Security Configuration ########
plugins.security.ssl.transport.pemcert_filepath: node.pem
plugins.security.ssl.transport.pemkey_filepath: node-key.pem
plugins.security.ssl.transport.pemtrustedcas_filepath: root-ca.pem
plugins.security.ssl.transport.enforce_hostname_verification: false

# Disable ssl at REST as Fulltextsearch can't accept self-signed CA certs.
plugins.security.ssl.http.enabled: false
#plugins.security.ssl.http.pemcert_filepath: node.pem
#plugins.security.ssl.http.pemkey_filepath: node-key.pem
#plugins.security.ssl.http.pemtrustedcas_filepath: root-ca.pem
plugins.security.allow_unsafe_democertificates: false
plugins.security.allow_default_init_securityindex: true
plugins.security.authcz.admin_dn:
  - 'CN=admin,OU=FTS,O=OPENSEARCH,L=FTS,ST=OPENSEARCH,,C=CA'
plugins.security.nodes_dn:
  - 'CN=${DOMAIN},OU=FTS,O=OPENSEARCH,L=FTS,ST=OPENSEARCH,C=CA'

plugins.security.audit.type: internal_opensearch
plugins.security.enable_snapshot_restore_privilege: true
plugins.security.check_snapshot_restore_write_privileges: true
plugins.security.restapi.roles_enabled: ["all_access", "security_rest_api_access"]
plugins.security.system_indices.enabled: true
plugins.security.system_indices.indices: [".opendistro-alerting-config", ".opendistro-alerting-alert*", ".opendistro-anomaly-results*", ".opendistro-anomaly-detector*", ".opendistro-anomaly-checkpoints", ".opendistro-anomaly-detection-state", ".opendistro-reports-*", ".opendistro-notifications-*", ".opendistro-notebooks", ".opensearch-observability", ".opendistro-asynchronous-search-response*", ".replication-metadata-store"]
node.max_local_storage_nodes: 1
######## End Security Configuration ########
YML_OPENSEARCH

# internal_users.yml
cat << YML_INTERNAL_USERS > $OPNSDIR/internal_users.yml
_meta:
  type: "internalusers"
  config_version: 2

${INDEX_USER}:
  hash: "${BCRYPT_HASH}"
  reserved: true
  backend_roles:
  - "admin"
  description: "admin user for fts at opensearch."
YML_INTERNAL_USERS

# roles_mapping.yml
cat << YML_ROLES_MAPPING > $OPNSDIR/roles_mapping.yml
_meta:
  type: "rolesmapping"
  config_version: 2

# Roles mapping
all_access:
  reserved: false
  backend_roles:
  - "admin"
  description: "Maps admin to all_access"
YML_ROLES_MAPPING

# docker-compose.yml
cat << YML_DOCKER_COMPOSE > $OPNSDIR/docker-compose.yml
version: '3'
services:
  fts_os-node:
    image: $opens_fts
    container_name: fts_os-node
    restart: always
    command:
      - sh
      - -c
      - "/usr/share/opensearch/bin/opensearch-plugin list | grep -q ingest-attachment \
         || /usr/share/opensearch/bin/opensearch-plugin install --batch ingest-attachment ;
         ./opensearch-docker-entrypoint.sh"
    environment:
      - cluster.name=fts_os-cluster
      - node.name=fts_os-node
      - bootstrap.memory_lock=true
      - "OPENSEARCH_JAVA_OPTS=-Xms1024M -Xmx1024M"
    ulimits:
      memlock:
        soft: -1
        hard: -1
      nofile:
        soft: 65536
        hard: 65536
    volumes:
      - fts_os-data:/usr/share/opensearch/data
      - $OPNSDIR/root-ca.pem:/usr/share/opensearch/config/root-ca.pem
      - $OPNSDIR/node.pem:/usr/share/opensearch/config/node.pem
      - $OPNSDIR/node-key.pem:/usr/share/opensearch/config/node-key.pem
      - $OPNSDIR/admin.pem:/usr/share/opensearch/config/admin.pem
      - $OPNSDIR/admin-key.pem:/usr/share/opensearch/config/admin-key.pem
      - $OPNSDIR/opensearch.yml:/usr/share/opensearch/config/opensearch.yml
      - $OPNSDIR/internal_users.yml:/usr/share/opensearch/plugins/opensearch-security/securityconfig/internal_users.yml
      - $OPNSDIR/roles_mapping.yml:/usr/share/opensearch/plugins/opensearch-security/securityconfig/roles_mapping.yml
    ports:
      - 127.0.0.1:9200:9200
      - 127.0.0.1:9600:9600 # Performance Analyzer [1]
    networks:
      - fts_os-net

volumes:
  fts_os-data:

networks:
  fts_os-net:

#[1] https://github.com/opensearch-project/performance-analyzer
YML_DOCKER_COMPOSE

# Prepare certs
create_certs "$DOMAIN"

# Set permissions
chmod 744 -R  $OPNSDIR

# Launch docker-compose
cd $OPNSDIR
docker-compose up -d

# Wait for bootstrapping
if [ "$(nproc)" -gt 2 ]
then
    countdown "Waiting for Docker bootstrapping..." "30"
else
    countdown "Waiting for Docker bootstrapping..." "60"
fi

# Make sure password setup is enforced.
docker-compose exec fts_os-node \
    bash -c "cd \
             plugins/opensearch-security/tools/ && \
             bash securityadmin.sh -f \
             ../securityconfig/internal_users.yml \
             -t internalusers \
             -icl \
             -nhnv \
             -cacert ../../../config/root-ca.pem \
             -cert ../../../config/admin.pem \
             -key ../../../config/admin-key.pem && \
             chmod 0600 ../../../config/root-ca.pem \
                        ../../../config/admin.pem \
                        ../../../config/admin-key.pem"

docker logs $fts_node

printwc "$Green" "\n\nYou can now use: \"http://${INDEX_USER}:${OPNSREST}@localhost:9200\"\n"