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

有几种方法可以解析cmdline参数(例如GNU getopt(不可移植)vs BSD(MacOS)getopt vs getopts)-所有这些都有问题。此解决方案

是便携式的!没有依赖关系,仅依赖于bash内置允许短期和长期选项处理空格或同时在选项和参数之间使用=分隔符支持串联短选项样式-vxfhandles选项和可选参数(例如--color vs--color=always),正确检测和报告未知选项支持--表示选项结束,以及与相同功能集的替代方案相比,不需要代码膨胀。即简洁,因此易于维护

示例:任何

# flag
-f
--foo

# option with required argument
-b"Hello World"
-b "Hello World"
--bar "Hello World"
--bar="Hello World"

# option with optional argument
--baz
--baz="Optional Hello"

#!/usr/bin/env bash

usage() {
  cat - >&2 <<EOF
NAME
    program-name.sh - Brief description
 
SYNOPSIS
    program-name.sh [-h|--help]
    program-name.sh [-f|--foo]
                    [-b|--bar <arg>]
                    [--baz[=<arg>]]
                    [--]
                    FILE ...

REQUIRED ARGUMENTS
  FILE ...
          input files

OPTIONS
  -h, --help
          Prints this and exits

  -f, --foo
          A flag option
      
  -b, --bar <arg>
          Option requiring an argument <arg>

  --baz[=<arg>]
          Option that has an optional argument <arg>. If <arg>
          is not specified, defaults to 'DEFAULT'
  --     
          Specify end of options; useful if the first non option
          argument starts with a hyphen

EOF
}

fatal() {
    for i; do
        echo -e "${i}" >&2
    done
    exit 1
}

# For long option processing
next_arg() {
    if [[ $OPTARG == *=* ]]; then
        # for cases like '--opt=arg'
        OPTARG="${OPTARG#*=}"
    else
        # for cases like '--opt arg'
        OPTARG="${args[$OPTIND]}"
        OPTIND=$((OPTIND + 1))
    fi
}

# ':' means preceding option character expects one argument, except
# first ':' which make getopts run in silent mode. We handle errors with
# wildcard case catch. Long options are considered as the '-' character
optspec=":hfb:-:"
args=("" "$@")  # dummy first element so $1 and $args[1] are aligned
while getopts "$optspec" optchar; do
    case "$optchar" in
        h) usage; exit 0 ;;
        f) foo=1 ;;
        b) bar="$OPTARG" ;;
        -) # long option processing
            case "$OPTARG" in
                help)
                    usage; exit 0 ;;
                foo)
                    foo=1 ;;
                bar|bar=*) next_arg
                    bar="$OPTARG" ;;
                baz)
                    baz=DEFAULT ;;
                baz=*) next_arg
                    baz="$OPTARG" ;;
                -) break ;;
                *) fatal "Unknown option '--${OPTARG}'" "see '${0} --help' for usage" ;;
            esac
            ;;
        *) fatal "Unknown option: '-${OPTARG}'" "See '${0} --help' for usage" ;;
    esac
done

shift $((OPTIND-1))

if [ "$#" -eq 0 ]; then
    fatal "Expected at least one required argument FILE" \
    "See '${0} --help' for usage"
fi

echo "foo=$foo, bar=$bar, baz=$baz, files=${@}"

其他回答

# As long as there is at least one more argument, keep looping
while [[ $# -gt 0 ]]; do
    key="$1"
    case "$key" in
        # This is a flag type option. Will catch either -f or --foo
        -f|--foo)
        FOO=1
        ;;
        # Also a flag type option. Will catch either -b or --bar
        -b|--bar)
        BAR=1
        ;;
        # This is an arg value type option. Will catch -o value or --output-file value
        -o|--output-file)
        shift # past the key and to the value
        OUTPUTFILE="$1"
        ;;
        # This is an arg=value type option. Will catch -o=value or --output-file=value
        -o=*|--output-file=*)
        # No need to shift here since the value is part of the same string
        OUTPUTFILE="${key#*=}"
        ;;
        *)
        # Do whatever you want with extra options
        echo "Unknown option '$key'"
        ;;
    esac
    # Shift after checking all the cases to get the next option
    shift
done

这使您既可以使用空格分隔的选项/值,也可以使用相等的定义值。

因此,您可以使用以下命令运行脚本:

./myscript --foo -b -o /fizz/file.txt

以及:

./myscript -f --bar -o=/fizz/file.txt

并且两者应该具有相同的最终结果。

赞成的意见:

允许-arg=value和-arg-value适用于bash中可以使用的任何arg名称意思是-a或-arg或--arg或-ar-g或其他纯粹的狂欢。无需学习/使用getopt或getopts

欺骗:

无法组合参数意思是没有-abc。您必须执行-a-b-c

使用bash模块中的模块“参数”

例子:

#!/bin/bash
. import.sh log arguments

NAME="world"

parse_arguments "-n|--name)NAME;S" -- "$@" || {
  error "Cannot parse command line."
  exit 1
}

info "Hello, $NAME!"

另一个Shell参数分析器(ASAP)

符合POSIX,无getopt

我受到@bronson相对简单的回答的启发,并试图改进它(不增加太多复杂性)。结果如下:

使用-n[arg]、-abn[arg],--name[arg]和--name=arg样式中的任意一种选项;参数可以按任何顺序出现,循环后$@中只留下位置参数;使用--强制将剩余的参数视为位置参数;检测无效选项和缺少的参数;不依赖于getopt或外部工具(一个功能使用简单的sed命令);便携式,紧凑,可读性强,具有独立功能。

# Convenience functions.
usage_error () { echo >&2 "$(basename $0):  $1"; exit 2; }
assert_argument () { test "$1" != "$EOL" || usage_error "$2 requires an argument"; }

# One loop, nothing more.
if [ "$#" != 0 ]; then
  EOL=$(printf '\1\3\3\7')
  set -- "$@" "$EOL"
  while [ "$1" != "$EOL" ]; do
    opt="$1"; shift
    case "$opt" in

      # Your options go here.
      -f|--flag) flag='true';;
      -n|--name) assert_argument "$1" "$opt"; name="$1"; shift;;

      # Arguments processing. You may remove any unneeded line after the 1st.
      -|''|[!-]*) set -- "$@" "$opt";;                                          # positional argument, rotate to the end
      --*=*)      set -- "${opt%%=*}" "${opt#*=}" "$@";;                        # convert '--name=arg' to '--name' 'arg'
      -[!-]?*)    set -- $(echo "${opt#-}" | sed 's/\(.\)/ -\1/g') "$@";;       # convert '-abc' to '-a' '-b' '-c'
      --)         while [ "$1" != "$EOL" ]; do set -- "$@" "$1"; shift; done;;  # process remaining arguments as positional
      -*)         usage_error "unknown option: '$opt'";;                        # catch misspelled options
      *)          usage_error "this should NEVER happen ($opt)";;               # sanity test for previous patterns

    esac
  done
  shift  # $EOL
fi

# Do something cool with "$@"... \o/

注:我知道。。。二进制模式为0x01030307的参数可能会破坏逻辑。但是,如果有人在命令行中传递这样的参数,他们应该得到它。

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

我使用optget和optgets的组合来解析带或不带参数的短选项和长选项,甚至是非选项(不带-或-的选项):

# catch wrong options and move non-options to the end of the string
args=$(getopt -l "$opt_long" "$opt_short" "$@" 2> >(sed -e 's/^/stderr/g')) || echo -n "Error: " && echo "$args" | grep -oP "(?<=^stderr).*" && exit 1
mapfile -t args < <(xargs -n1 <<< "$(echo "$args" | sed -E "s/(--[^ ]+) /\1=/g")" )
set -- "${args[@]}"

# parse short and long options
while getopts "$opt_short-:" opt; do
  ...
done

# remove all parsed options from $@
shift $((OPTIND-1)

这样,我就可以使用$opt_verbose这样的变量访问所有选项,而非选项可以通过默认变量$1、$2等访问:

echo "help:$opt_help"
echo "file:$opt_file"
echo "verbose:$opt_verbose"
echo "long_only:$opt_long_only"
echo "short_only:$opt_s"
echo "path:$1"
echo "mail:$2"

其中一个主要特点是,我能够以完全随机的顺序传递所有选项和非选项:

#             $opt_file     $1        $2          $opt_... $opt_... $opt_...
# /demo.sh --file=file.txt /dir info@example.com -V -h --long_only=yes -s
help:1
file:file.txt
verbose:1
long_only:yes
short_only:1
path:/dir
mail:info@example.com

更多详情:https://stackoverflow.com/a/74275254/318765