Playing around with a pure-ish bash IMDB-ish client for fun

imdb.sh

#!/usr/bin/env bash

set -Eeuo pipefail

trap 'declare rc=$?;
      >&2 echo "Unexpected error executing $BASH_COMMAND at ${BASH_SOURCE[0]} line $LINENO";
      exit $rc' ERR

join () {
  local IFS="$1"; shift
  echo "$*"
}

omdbapi () {
  declare host="$1"; shift
  declare query="$(join "&" "$@")"
  declare data="" body=""
  data="$(get_url "$host" "$query")"
  while read -r out ; do
    out="${out%%$'\r'}"
    if [[ ! $body && -z "$out" ]] ; then
      body=true
    elif [[ $body ]] ; then
      echo "$out"
    fi
  done < <(echo "$data") | {
    declare rc=${PIPESTATUS[0]}
    if type -P jq >/dev/null ; then
      jq .
    else
      cat
    fi
    return $rc
  }
}

get_url () {
  declare host="$1" query="$2"
  exec 3<>"/dev/tcp/$host/80"
  printf "GET /?%s HTTP/1.1\r\nhost: %s\r\nConnection: close\r\n\r\n" \
   "$query" "$host" >&3
  cat <&3
}

main () {
  declare -r api_host="www.omdbapi.com"
  declare api_key="${OMDB_APIKEY:-$(cat ~/.omdb.apikey 2>/dev/null||:)}"

  if [[ -z "$api_key" ]] ; then
    >&2 echo "Missing OMDB_APIKEY environment variable or ~/.omdb.apikey file; exiting!"
    exit 1
  fi
  if [[ $# -lt 1 ]] ; then
    >&2 echo "Syntax: ${BASH_SOURCE[0]##*/} <movie title>"
    exit 64
  fi

  omdbapi "$api_host" "apikey=$api_key" "plot=full" "t=$*"
}

main "$@"