prologic-saltyim/bin/salty-chat.sh

#!/bin/sh

set -e

# Validate environment
if ! command -v jq > /dev/null; then
  printf "missing jq command. Please install it via your system's package manager\n"
  exit 1
fi

if ! command -v msgbus > /dev/null; then
  printf "missing msgbus command. Use:  go install git.mills.io/prologic/msgbus/cmd/msgbus@master\n"
  exit 1
fi

for cmd in salty salty-keygen; do
  if ! command -v $cmd > /dev/null; then
    printf "missing %s command. Use go install go.mills.io/salty/cmd/$cmd@master\n" "$cmd"
    exit 1
  fi
done

if [ -n "$XDG_CONFIG_HOME" ]; then
  data_path="$XDG_CONFIG_HOME/salty"
else
  data_path="$HOME/.config/salty"
fi

if [ -z "$SALTY_IDENTITY" ]; then
  export SALTY_IDENTITY="$data_path/$USER.key"
fi

clear_line() {
  printf '\r\033[2K'
}

move_cursor_up() {
  printf '\033[1A'
}

get_user () {
  user=$(grep user: "$SALTY_IDENTITY" | awk '{print $3}')
  if [ -z "$user" ]; then
    user="$USER"
  fi
  echo "$user"
}

format_message() {
  me="$1"
  message="$2"
  printf "%s\t(%s)\t%s" "$(date -u +%FT%TZ)" "$me" "$message"
}

stream () {
  if [ -z "$SALTY_IDENTITY" ]; then
    echo "SALTY_IDENTITY not set"
    return 2
  fi

  sig=$(mktemp /tmp/salty.XXXXXX)
  msg="$(jq -r '.payload' | base64 -d | salty -i "$SALTY_IDENTITY" -d 2> "$sig")"

  if [ -n "$SALTY_CHATWITH" ]; then
    if ! echo "$msg" | grep -q "\t($SALTY_CHATWITH)" > /dev/null; then
      exit
    fi
  fi

  echo '\007'

  if [ -n "$SALTY_CHATKEY" ]; then
    if ! grep -q "$SALTY_CHATKEY" "$sig" > /dev/null; then
      echo "[warning key does not match!] $(cat "$sig") != $SALTY_CHATKEY"
    fi
  fi
  rm "$sig"

  move_cursor_up
  clear_line
  echo "$msg" # | lextwt-cli -salty | jq -r '[.created,.twter.nick,.text]|@csv'
  printf ">"
}

lookup () {
  if [ $# -lt 1 ]; then
    printf "lookup takes 1 arugment %d given\n" "$#"
    printf "Try %s lookup nick@domain\n" "$(basename "$0")"
    return 1
  fi

  user="$1"
  nick="$(echo "$user" | awk -F@ '{ print $1 }')"
  domain="$(echo "$user" | awk -F@ '{ print $2 }')"
  hash="$(printf "%s" "$user" | sha256sum | cut -f 1 -d ' ')"

  discovery_host="$(dig +short SRV _salty._tcp."$domain" | cut -f 4 -d' ')"
  if [ -z "$discovery_host" ]; then
    discovery_host="$domain"
  fi

  info=$(mktemp /tmp/salty.XXXXXX)
  if ! curl -qfsSL "https://$discovery_host/.well-known/salty/${hash}.json" > "$info" 2> /dev/null; then
    if ! curl -qfsSL "https://$discovery_host/.well-known/salty/${nick}.json" > "$info"; then
      rm "$info"
      echo "error: lookup failed"
      return 1
    fi
  fi

  cat "$info"
  rm "$info"
}

readmsgs () {
  topic="$1"

  if [ -z "$topic" ]; then
    me="$(get_user)"
    topic="$(echo "$me" | awk -F@ '{ print $1 }')"
  fi

  export SALTY_IDENTITY="$data_path/$topic.key"
  if [ ! -f "$SALTY_IDENTITY" ]; then
    echo "identity file missing for user $topic" >&2
    return 1
  fi

  msgbus sub "$topic" "$0"
}

sendmsg () {
  if [ $# -lt 2 ]; then
    printf "sendmsg requires 2 arguments %d provided\n" "$#"
    printf "Try %s send nick@domain message\n" "$(basename "$0")"
    return 1
  fi

  if [ -z "$SALTY_IDENTITY" ]; then
    echo "SALTY_IDENTITY not set"
    return 2
  fi

  user="$1"
  message="$2"

  if [ -z "$message" ]; then
    echo "error: empty message"
    exit 2
  fi

  salty_json="$(mktemp /tmp/salty.XXXXXX)"

  lookup "$user" > "$salty_json"

  endpoint="$(jq -r '.endpoint' < "$salty_json")"
  key="$(jq -r '.key' < "$salty_json")"

  # XXX: Deprecated as of Spec v1.1
  # XXX: There is only an Endpoint
  if topic="$(jq -e -r '.topic' < "$salty_json")"; then
    endpoint="$endpoint/$topic"
  fi

  rm "$salty_json"

  me="$(get_user)"

  format_message "$me" "$message" \
    | salty -i "$SALTY_IDENTITY" -r "$key" \
    | curl -fqsS --data-binary @- "$endpoint"
}

chatwith() {
  if [ $# -lt 1 ]; then
    printf "chatwith requires 1 arguments %d provided\n" "$#"
    printf "Try %s chat nick@domain\n" "$(basename "$0")"
    return 1
  fi

  if [ -z "$SALTY_IDENTITY" ]; then
    echo "SALTY_IDENTITY not set"
    return 2
  fi

  user="$1"

  salty_json="$(mktemp /tmp/salty.XXXXXX)"

  lookup "$user" > "$salty_json"

  endpoint="$(jq -r '.endpoint' < "$salty_json")"
  key="$(jq -r '.key' < "$salty_json")"

  # XXX: Deprecated as of Spec v1.1
  # XXX: There is only an Endpoint
  if topic="$(jq -e -r '.topic' < "$salty_json")"; then
    endpoint="$endpoint/$topic"
  fi

  rm "$salty_json"

  me="$(get_user)"
  nick="$(echo "$me" | awk -F@ '{ print $1 }')"
  domain="$(echo "$me" | awk -F@ '{ print $2 }')"

  export SALTY_CHATWITH="$user"
  export SALTY_CHATKEY="$key"
  echo chat with "$SALTY_CHATWITH" via "$endpoint" key "$key"

  readmsgs "$nick" &
  READ_PID=$$
  trap 'kill $READ_PID' EXIT

  while true; do
    printf "> "
    read -r message
    clear_line
    if [ -z "$message" ]; then
      continue
    fi

    format_message "$me" "$message" \
      | salty -i "$SALTY_IDENTITY" -r "$key" \
      | curl -fqsS --data-binary @- "$endpoint"

    move_cursor_up
    clear_line

    format_message "$me" "$message"
    echo
  done
}

make_user () {
  mkdir -p "$data_path"

  if [ $# -lt 1 ]; then
    user=$USER
  else
    user=$1
  fi

  identity_file="$data_path/$user.key"

  if [ -f "$identity_file" ]; then
    printf "user key already exists!"
    return 1
  fi

  # Check for msgbus env.. probably can make it fallback to looking for a config file?
  if [ -z "$MSGBUS_URI" ]; then
    printf "missing MSGBUS_URI in environment"
    return 1
  fi

  salty-keygen -o "$identity_file"
  echo "# user: $user" >> "$identity_file"

  pubkey=$(grep key: "$identity_file" | awk '{print $4}')
  hash="$(printf "%s" "$user" | sha256sum | cut -f 1 -d ' ')"
  cat <<- EOF
Create this file in your webserver well-known folder. https://hostname.tld/.well-known/salty/$hash.json

{
  "endpoint": "$MSGBUS_URI/$user",
  "key": "$pubkey"
}

EOF
}

show_help() {
  printf "Usage: %s [options] <command> [arguments]\n" "$(basename "$0")"
  printf "\n"
  printf "Options:\n"
  printf "  -h/--help  Show this help"
  printf "\n"
  printf "\n"
  printf "Commands:\n"
  printf "  help       -- Display this help message\n"
  printf "  chat       -- Chat with a user by nick@domain\n"
  printf "  lookup     -- Lookup a user by nick@domain\n"
  printf "  make-user  -- Generate a new user key pair\n"
  printf "  read       -- Reads your messages\n"
  printf "  send       -- Sends a message to nick@domain\n"
}

# check if streaming
if [ ! -t 1 ]; then
  stream
  exit 0
fi

# Show Help
if [ $# -lt 1 ]; then
  show_help
  exit 1
fi


CMD=$1
shift

case $CMD in
  -h|--help|help)
    show_help
  ;;
  chat)
    chatwith "$@"
  ;;
  send)
    sendmsg "$@"
  ;;
  read)
    readmsgs "$@"
  ;;
  lookup)
    lookup "$@"
  ;;
  make-user)
    make_user "$@"
  ;;
esac