比如,我有一个脚本,用这行代码调用:

./myscript -vfd ./foo/bar/someFile -o /fizz/someOtherFile

或者这个:

./myscript -v -f -d -o /fizz/someOtherFile ./foo/bar/someFile 

什么是公认的解析方式,以便在每种情况下(或两者的某种组合)$v、$f和$d都将设置为true,而$outFile将等于/fiz/someOtherFile?


当前回答

此示例显示了如何使用getopt和eval以及HEREDOC和shift来处理短参数和长参数,以及是否具有以下所需值。此外,switch/case语句简洁易懂。

#!/usr/bin/env bash

# usage function
function usage()
{
   cat << HEREDOC

   Usage: $progname [--num NUM] [--time TIME_STR] [--verbose] [--dry-run]

   optional arguments:
     -h, --help           show this help message and exit
     -n, --num NUM        pass in a number
     -t, --time TIME_STR  pass in a time string
     -v, --verbose        increase the verbosity of the bash script
     --dry-run            do a dry run, dont change any files

HEREDOC
}  

# initialize variables
progname=$(basename $0)
verbose=0
dryrun=0
num_str=
time_str=

# use getopt and store the output into $OPTS
# note the use of -o for the short options, --long for the long name options
# and a : for any option that takes a parameter
OPTS=$(getopt -o "hn:t:v" --long "help,num:,time:,verbose,dry-run" -n "$progname" -- "$@")
if [ $? != 0 ] ; then echo "Error in command line arguments." >&2 ; usage; exit 1 ; fi
eval set -- "$OPTS"

while true; do
  # uncomment the next line to see how shift is working
  # echo "\$1:\"$1\" \$2:\"$2\""
  case "$1" in
    -h | --help ) usage; exit; ;;
    -n | --num ) num_str="$2"; shift 2 ;;
    -t | --time ) time_str="$2"; shift 2 ;;
    --dry-run ) dryrun=1; shift ;;
    -v | --verbose ) verbose=$((verbose + 1)); shift ;;
    -- ) shift; break ;;
    * ) break ;;
  esac
done

if (( $verbose > 0 )); then

   # print out all the parameters we read in
   cat <<EOM
   num=$num_str
   time=$time_str
   verbose=$verbose
   dryrun=$dryrun
EOM
fi

# The rest of your script below

以上脚本中最重要的几行是:

OPTS=$(getopt -o "hn:t:v" --long "help,num:,time:,verbose,dry-run" -n "$progname" -- "$@")
if [ $? != 0 ] ; then echo "Error in command line arguments." >&2 ; exit 1 ; fi
eval set -- "$OPTS"

while true; do
  case "$1" in
    -h | --help ) usage; exit; ;;
    -n | --num ) num_str="$2"; shift 2 ;;
    -t | --time ) time_str="$2"; shift 2 ;;
    --dry-run ) dryrun=1; shift ;;
    -v | --verbose ) verbose=$((verbose + 1)); shift ;;
    -- ) shift; break ;;
    * ) break ;;
  esac
done

简短,切中要害,可读,处理几乎所有的事情(IMHO)。

希望这对某人有所帮助。

其他回答

我认为这个很简单:

#!/bin/bash
#

readopt='getopts $opts opt;rc=$?;[ "$rc$opt" = "0?" ]&&exit 1;[ $rc = 0 ]||{ shift $[OPTIND-1];false; }'

opts=vfdo:

# Enumerating options
while eval "$readopt"
do
    echo OPT:$opt ${OPTARG+OPTARG:$OPTARG}
done

# Enumerating arguments
for arg
do
    echo ARG:$arg
done

调用示例:

./myscript -v -do /fizz/someOtherFile -f ./foo/bar/someFile
OPT:v 
OPT:d 
OPT:o OPTARG:/fizz/someOtherFile
OPT:f 
ARG:./foo/bar/someFile

我使用它从末尾迭代key=>值。循环后捕获第一个可选参数。

用法为/script.sh可选的第一个参数-key value-key2 value2

#!/bin/sh

a=$(($#-1))
b=$(($#))
while [ $a -gt 0 ]; do
    eval 'key="$'$a'"; value="$'$b'"'
    echo "$key => $value"
    b=$(($b-2))
    a=$(($a-2))
done
unset a b key value

[ $(($#%2)) -ne 0 ] && echo "first_arg = $1"

当然,你可以从左到右做一些改变。

此代码段显示key=>值对和第一个参数(如果存在)。

#!/bin/sh

a=$((1+$#%2))
b=$((1+$a))

[ $(($#%2)) -ne 0 ] && echo "first_arg = $1"

while [ $a -lt $# ]; do
    eval 'key="$'$a'"; value="$'$b'"'
    echo "$key => $value"
    b=$(($b+2))
    a=$(($a+2))
done

unset a b key value

测试了100000个参数,速度很快。

您还可以从左到右迭代key=>value和第一个可选arg,而不使用eval:

#!/bin/sh

a=$(($#%2))
b=0

[ $a -eq 1 ] && echo "first_arg = $1"

for value; do
    if [ $b -gt $a -a $(($b%2)) -ne $a ]; then
        echo "$key => $value"
    fi
    key="$value"
    b=$((1+$b))
done

unset a b key value

while [ "$#" -gt 0 ]; do
  case "$1" in
    -n) name="$2"; shift 2;;
    -p) pidfile="$2"; shift 2;;
    -l) logfile="$2"; shift 2;;

    --name=*) name="${1#*=}"; shift 1;;
    --pidfile=*) pidfile="${1#*=}"; shift 1;;
    --logfile=*) logfile="${1#*=}"; shift 1;;
    --name|--pidfile|--logfile) echo "$1 requires an argument" >&2; exit 1;;
    
    -*) echo "unknown option: $1" >&2; exit 1;;
    *) handle_argument "$1"; shift 1;;
  esac
done

此解决方案:

句柄-n arg和--name=arg允许在末尾使用参数如果有任何拼写错误,则显示正常错误兼容,不使用抨击可读,不需要在循环中维护状态

我给你一个函数parse_params,它将从命令行解析参数。

这是一个纯Bash解决方案,没有额外的实用程序。不会污染全球范围。轻松地返回简单易用的变量,您可以在这些变量上构建进一步的逻辑。params前面的破折号数量无关紧要(--all等于-all等于all=all)

下面的脚本是复制粘贴工作演示。请参见show_use函数以了解如何使用parse_param。

限制:

不支持空格分隔的参数(-d 1)参数名称将丢失破折号,因此--any参数和-anyparam等效eval$(parse_params“$@”)必须在bash函数中使用(它在全局范围内不起作用)


#!/bin/bash

# Universal Bash parameter parsing
# Parse equal sign separated params into named local variables
# Standalone named parameter value will equal its param name (--force creates variable $force=="force")
# Parses multi-valued named params into an array (--path=path1 --path=path2 creates ${path[*]} array)
# Puts un-named params as-is into ${ARGV[*]} array
# Additionally puts all named params as-is into ${ARGN[*]} array
# Additionally puts all standalone "option" params as-is into ${ARGO[*]} array
# @author Oleksii Chekulaiev
# @version v1.4.1 (Jul-27-2018)
parse_params ()
{
    local existing_named
    local ARGV=() # un-named params
    local ARGN=() # named params
    local ARGO=() # options (--params)
    echo "local ARGV=(); local ARGN=(); local ARGO=();"
    while [[ "$1" != "" ]]; do
        # Escape asterisk to prevent bash asterisk expansion, and quotes to prevent string breakage
        _escaped=${1/\*/\'\"*\"\'}
        _escaped=${_escaped//\'/\\\'}
        _escaped=${_escaped//\"/\\\"}
        # If equals delimited named parameter
        nonspace="[^[:space:]]"
        if [[ "$1" =~ ^${nonspace}${nonspace}*=..* ]]; then
            # Add to named parameters array
            echo "ARGN+=('$_escaped');"
            # key is part before first =
            local _key=$(echo "$1" | cut -d = -f 1)
            # Just add as non-named when key is empty or contains space
            if [[ "$_key" == "" || "$_key" =~ " " ]]; then
                echo "ARGV+=('$_escaped');"
                shift
                continue
            fi
            # val is everything after key and = (protect from param==value error)
            local _val="${1/$_key=}"
            # remove dashes from key name
            _key=${_key//\-}
            # skip when key is empty
            # search for existing parameter name
            if (echo "$existing_named" | grep "\b$_key\b" >/dev/null); then
                # if name already exists then it's a multi-value named parameter
                # re-declare it as an array if needed
                if ! (declare -p _key 2> /dev/null | grep -q 'declare \-a'); then
                    echo "$_key=(\"\$$_key\");"
                fi
                # append new value
                echo "$_key+=('$_val');"
            else
                # single-value named parameter
                echo "local $_key='$_val';"
                existing_named=" $_key"
            fi
        # If standalone named parameter
        elif [[ "$1" =~ ^\-${nonspace}+ ]]; then
            # remove dashes
            local _key=${1//\-}
            # Just add as non-named when key is empty or contains space
            if [[ "$_key" == "" || "$_key" =~ " " ]]; then
                echo "ARGV+=('$_escaped');"
                shift
                continue
            fi
            # Add to options array
            echo "ARGO+=('$_escaped');"
            echo "local $_key=\"$_key\";"
        # non-named parameter
        else
            # Escape asterisk to prevent bash asterisk expansion
            _escaped=${1/\*/\'\"*\"\'}
            echo "ARGV+=('$_escaped');"
        fi
        shift
    done
}

#--------------------------- DEMO OF THE USAGE -------------------------------

show_use ()
{
    eval $(parse_params "$@")
    # --
    echo "${ARGV[0]}" # print first unnamed param
    echo "${ARGV[1]}" # print second unnamed param
    echo "${ARGN[0]}" # print first named param
    echo "${ARG0[0]}" # print first option param (--force)
    echo "$anyparam"  # print --anyparam value
    echo "$k"         # print k=5 value
    echo "${multivalue[0]}" # print first value of multi-value
    echo "${multivalue[1]}" # print second value of multi-value
    [[ "$force" == "force" ]] && echo "\$force is set so let the force be with you"
}

show_use "param 1" --anyparam="my value" param2 k=5 --force --multi-value=test1 --multi-value=test2

另一个选项解析器(生成器)

用于shell脚本的优雅选项解析器(完全支持所有POSIX shell)https://github.com/ko1nksm/getoptions(更新:v3.3.0于2021-05-02发布)

getoptions是一个新的选项解析器(生成器),用POSIX兼容的shell脚本编写,于2020年8月发布。它适用于那些希望在shell脚本中支持POSIX/GNU样式选项语法的人。

支持的语法有-a、+a、-abc、-vvv、-p VALUE、-pVALUE、--flag、--no flag、--带flag、---不带flag,--param VALUE,--param=VALUE,--option[=VALUE],--no option--。

它支持子命令、验证、缩写选项和自动帮助生成。并且适用于所有POSIX shell(dash 0.5.4+、bash 2.03+、ksh88+、mksh R28+、zsh 3.1.9+、yash 2.29+、busybox ash 1.1.3+等)。

#!/bin/sh

VERSION="0.1"

parser_definition() {
  setup   REST help:usage -- "Usage: example.sh [options]... [arguments]..." ''
  msg -- 'Options:'
  flag    FLAG    -f --flag                 -- "takes no arguments"
  param   PARAM   -p --param                -- "takes one argument"
  option  OPTION  -o --option on:"default"  -- "takes one optional argument"
  disp    :usage  -h --help
  disp    VERSION    --version
}

eval "$(getoptions parser_definition) exit 1"

echo "FLAG: $FLAG, PARAM: $PARAM, OPTION: $OPTION"
printf '%s\n' "$@" # rest arguments

它解析以下参数:

example.sh -f --flag -p VALUE --param VALUE -o --option -oVALUE --option=VALUE 1 2 3

以及自动生成帮助。

$ example.sh --help

Usage: example.sh [options]... [arguments]...

Options:
  -f, --flag                  takes no arguments
  -p, --param PARAM           takes one argument
  -o, --option[=OPTION]       takes one optional argument
  -h, --help
      --version

它也是一个选项解析器生成器,生成以下简单的选项解析代码。如果使用生成的代码,则不需要getoptions。实现真正的可移植性和零依赖性。

FLAG=''
PARAM=''
OPTION=''
REST=''
getoptions_parse() {
  OPTIND=$(($#+1))
  while OPTARG= && [ $# -gt 0 ]; do
    case $1 in
      --?*=*) OPTARG=$1; shift
        eval 'set -- "${OPTARG%%\=*}" "${OPTARG#*\=}"' ${1+'"$@"'}
        ;;
      --no-*|--without-*) unset OPTARG ;;
      -[po]?*) OPTARG=$1; shift
        eval 'set -- "${OPTARG%"${OPTARG#??}"}" "${OPTARG#??}"' ${1+'"$@"'}
        ;;
      -[fh]?*) OPTARG=$1; shift
        eval 'set -- "${OPTARG%"${OPTARG#??}"}" -"${OPTARG#??}"' ${1+'"$@"'}
        OPTARG= ;;
    esac
    case $1 in
      '-f'|'--flag')
        [ "${OPTARG:-}" ] && OPTARG=${OPTARG#*\=} && set "noarg" "$1" && break
        eval '[ ${OPTARG+x} ] &&:' && OPTARG='1' || OPTARG=''
        FLAG="$OPTARG"
        ;;
      '-p'|'--param')
        [ $# -le 1 ] && set "required" "$1" && break
        OPTARG=$2
        PARAM="$OPTARG"
        shift ;;
      '-o'|'--option')
        set -- "$1" "$@"
        [ ${OPTARG+x} ] && {
          case $1 in --no-*|--without-*) set "noarg" "${1%%\=*}"; break; esac
          [ "${OPTARG:-}" ] && { shift; OPTARG=$2; } || OPTARG='default'
        } || OPTARG=''
        OPTION="$OPTARG"
        shift ;;
      '-h'|'--help')
        usage
        exit 0 ;;
      '--version')
        echo "${VERSION}"
        exit 0 ;;
      --)
        shift
        while [ $# -gt 0 ]; do
          REST="${REST} \"\${$(($OPTIND-$#))}\""
          shift
        done
        break ;;
      [-]?*) set "unknown" "$1"; break ;;
      *)
        REST="${REST} \"\${$(($OPTIND-$#))}\""
    esac
    shift
  done
  [ $# -eq 0 ] && { OPTIND=1; unset OPTARG; return 0; }
  case $1 in
    unknown) set "Unrecognized option: $2" "$@" ;;
    noarg) set "Does not allow an argument: $2" "$@" ;;
    required) set "Requires an argument: $2" "$@" ;;
    pattern:*) set "Does not match the pattern (${1#*:}): $2" "$@" ;;
    notcmd) set "Not a command: $2" "$@" ;;
    *) set "Validation error ($1): $2" "$@"
  esac
  echo "$1" >&2
  exit 1
}
usage() {
cat<<'GETOPTIONSHERE'
Usage: example.sh [options]... [arguments]...

Options:
  -f, --flag                  takes no arguments
  -p, --param PARAM           takes one argument
  -o, --option[=OPTION]       takes one optional argument
  -h, --help
      --version
GETOPTIONSHERE
}