urlencode.bash

#!/bin/bash
# vim:set ts=4 sw=4 tw=80 et ai si:
# ( settings from: http://datapax.com.au/code_conventions/ )
#
#/**********************************************************************
#    URL Encode
#    Copyright (C) 2016-2017 Todd Harbour
#
#    This program is free software; you can redistribute it and/or
#    modify it under the terms of the GNU General Public License
#    version 2 ONLY, as published by the Free Software Foundation.
#
#    This program is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#    GNU General Public License for more details.
#
#    You should have received a copy of the GNU General Public License
#    along with this program, in the file COPYING or COPYING.txt; if
#    not, see http://www.gnu.org/licenses/ , or write to:
#      The Free Software Foundation, Inc.,
#      51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
# **********************************************************************/

# urlencode
#----------
# An encoder for URLs, obeying RFC3986 (similar to PHP's rawurlencode)

# Config paths
_ETC_CONF="/etc/urlencode.conf"
_HOME_CONF="${HOME}/.urlencoderc"



############### STOP ###############
#
# Do NOT edit the CONFIGURATION below. Instead generate the default
# configuration file in your home directory thusly:
#
#     ./urlencode.bash -C >~/.urlencoderc
# or system wide:
#     ./urlencode.bash -C >/etc/urlencode.conf
#
####################################

# [ CONFIG_START

# URL Encode Default Configuration
# ================================

# DEBUG
#   This defines debug mode which will output verbose info to stderr
#   or, if configured, the debug file ( ERROR_LOG ).
DEBUG=0

# FILEPATH
#   If set, all URLs parsed will be assumed to be paths to files and as such
#   will NOT have their '/' characters encoded.
FILEPATH=0

# ALL
#   If set, all URLs parsed will have ALL characters encoded, not just those
#   required by RFC3986. The FILEPATH setting will still be observed if set.
ALL=0

# ERROR_LOG
#   The file to output errors and debug statements (when DEBUG != 0) instead of
#   stderr.
#ERROR_LOG="/tmp/urlencode.log"

# ] CONFIG_END

###
# Config loading
###
[ ! -z "${_ETC_CONF}"  ] && [ -r "${_ETC_CONF}"  ] && . "${_ETC_CONF}"
[ ! -z "${_HOME_CONF}" ] && [ -r "${_HOME_CONF}" ] && . "${_HOME_CONF}"

# Version
APP_NAME="URL Encode (urlencode)"
APP_VER="0.01"
APP_URL="http://gitlab.com/krayon/qdnxtools/urlencode.bash"

# Program name
PROG="$(basename "${0}")"

# exit condition constants
ERR_NONE=0
ERR_MISSINGDEP=1
ERR_UNKNOWNOPT=2
ERR_INVALIDOPT=3
ERR_MISSINGPARAM=4

# Defaults not in config



# Params:
#   NONE
function show_version() {
    echo -e "\
${APP_NAME} v${APP_VER}\n\
${APP_URL}\n\
"
}

# Params:
#   NONE
function show_usage() {
    show_version
cat <<EOF

${APP_NAME} encodes a URL, obeying RFC3986 (similar to PHP's rawurlencode)

Usage: ${PROG} -h|--help
       ${PROG} -V|--version
       ${PROG} -C|--configuration
       ${PROG} [-v|--verbose] [-f|--filepath] [-a|--all] [--] [-|<URL>]

-h|--help           - Displays this help
-V|--version        - Displays the program version
-C|--configuration  - Outputs the default configuration that can be placed in
                          ${_ETC_CONF}
                      or
                          ${_HOME_CONF}
                      for editing.
-v|--verbose        - Displays extra debugging information.  This is the same
                      as setting DEBUG=1 in your config.
-f|--filepath       - Informs ${PROG} that the URL(s) are file paths and ${PROG}
                      will therefore not encode '/'.
-a|--all            - Informs ${PROG} that you want ALL characters encoded, not
                      just those required by RFC3986 (-f|--filepath will still
                      be obeyed).
<URL>               - The URL to encode. If no text is specified, or <URL>
                      is "-" (minus/hyphen), then the URL(s) will be read from
                      stdin

Example: ${PROG} "http://www.google.com.au/search?btnI&q=youtube dQw4w9WgXcQ"
EOF
}

# Output configuration file
function output_config() {
    sed -n '/^# \[ CONFIG_START/,/^# \] CONFIG_END/p' <"${0}"
}

# Debug echo
function decho() {
    # Not debugging, get out of here then
    [ ${DEBUG} -le 0 ] && return

    echo "[$(date +'%Y-%m-%d %H:%M')] DEBUG: ${@}" >&2
}

# Encode URLs
function encodeurls() {
    while read -r url; do #{
        out=""
        for (( i = 0; i < ${#url}; ++i )); do #{
            case "${url:${i}:1}" in #{
                # Safe characters
                [-_.~a-zA-Z0-9])
                    if [ "${ALL}" -eq 1 ]; then #{
                        out="${out}$(printf '%%%2X' "'${url:${i}:1}'")"
                        continue
                    fi #}
                    out="${out}${url:${i}:1}"
                ;;

                # URI gen delimeters
                [:/?#\[\]@])
                    if [ "${url:${i}:1}" == "/" ] && [ "${FILEPATH}" -eq 1 ]; then #{
                        out="${out}/"
                        continue
                    fi #}
                    out="${out}$(printf '%%%2X' "'${url:${i}:1}'")"
                ;;

                # URI sub delimeters
                [\!\$\&\'\(\)\*\;=+,])
                    out="${out}$(printf '%%%2X' "'${url:${i}:1}'")"
                ;;

                *)
                    out="${out}$(printf '%%%2X' "'${url:${i}:1}'")"
                ;;
            esac #}
        done #}

        echo "${out}"
    done #}
}



# START #

# If debug file, redirect stderr out to it
[ ! -z "${ERROR_LOG}" ] && exec 2>>"${ERROR_LOG}"

decho "START"

# Check for required commands

# Process params
moreparams=1
decho "Processing ${#} params..."
while [ ${#} -gt 0 ]; do #{
    decho "Command line param: ${1}"

    [ ${moreparams} -gt 0 ] && {
        case "${1}" in #{
            # Verbose mode # [-v|--verbose]
            -v|--verbose)
                decho "Verbose mode specified"

                DEBUG=1

                shift 1; continue
            ;;

            # File path # [-f|--filepath]
            -f|--filepath)
                decho "File path mode specified"

                FILEPATH=1

                shift 1; continue
            ;;

            # ALL characters # [-a|--all]
            -a|--all)
                decho "ALL characters mode specified"

                ALL=1

                shift 1; continue
            ;;

            # Help # -h|--help
            -h|--help)
                decho "Help"

                show_usage
                exit ${ERR_NONE}
            ;;

            # Version # -V|--version
            -V|--version)
                decho "Version"

                show_version
                exit ${ERR_NONE}
            ;;

            # Configuration output # -C|--configuration
            -C|--configuration)
                decho "Configuration"

                output_config
                exit ${ERR_NONE}
            ;;

            *)
                [ "${1}" == "--" ] && {
                    # No more parameters to come
                    moreparams=0
                    shift 1; continue
                }

                [ "${1}" == "-" ] && {
                    # Read stdin
                    shift 1; continue
                }

                [ "${1:0:1}" == "-" ] && {
                    # Assume a parameter
                    echo "ERROR: Unrecognised parameter ${1}..." >&2
                    exit ${ERR_UNKNOWNOPT}
                }
            ;;

        esac #}
    }

    # URL
    decho "URL specified ( ${@} )"
    url="${@}"
    break
done #}

# If URL is specified
[ ! -z "${url}" ] && {
    echo "${url}"|encodeurls
    true

} || {
    encodeurls </dev/stdin
}

decho "DONE"