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

我写了一个脚本,可以帮助轻松解析命令行参数https://github.com/unfor19/bargs

示例

$ bash example.sh -n Willy --gender male -a 99
Name:      Willy
Age:       99
Gender:    male
Location:  chocolate-factory
$ bash example.sh -n Meir --gender male
[ERROR] Required argument: age

Usage: bash example.sh -n Willy --gender male -a 99

--person_name  |  -n  [Willy]              What is your name?
--age          |  -a  [Required]
--gender       |  -g  [Required]
--location     |  -l  [chocolate-factory]  insert your location
$ bash example.sh -h

Usage: bash example.sh -n Willy --gender male -a 99
--person_name  |  -n  [Willy]              What is your name?
--age          |  -a  [Required]
--gender       |  -g  [Required]
--location     |  -l  [chocolate-factory]  insert your location

其他回答

保留未处理参数的解决方案。包括演示。

这是我的解决方案。它非常灵活,不像其他软件包,不需要外部包,并且可以干净地处理遗留的参数。

用法为:/myscript-flag flag变量-otherflag flagvar2

您所要做的就是编辑有效标记行。它在前面加上连字符并搜索所有参数。然后它将下一个参数定义为标志名,例如。

./myscript -flag flagvariable -otherflag flagvar2
echo $flag $otherflag
flagvariable flagvar2

主要代码(简短的版本,详细的示例,以及错误输出的版本):

#!/usr/bin/env bash
#shebang.io
validflags="rate time number"
count=1
for arg in $@
do
    match=0
    argval=$1
    for flag in $validflags
    do
        sflag="-"$flag
        if [ "$argval" == "$sflag" ]
        then
            declare $flag=$2
            match=1
        fi
    done
        if [ "$match" == "1" ]
    then
        shift 2
    else
        leftovers=$(echo $leftovers $argval)
        shift
    fi
    count=$(($count+1))
done
#Cleanup then restore the leftovers
shift $#
set -- $leftovers

带有内置echo演示的详细版本:

#!/usr/bin/env bash
#shebang.io
rate=30
time=30
number=30
echo "all args
$@"
validflags="rate time number"
count=1
for arg in $@
do
    match=0
    argval=$1
#   argval=$(echo $@ | cut -d ' ' -f$count)
    for flag in $validflags
    do
            sflag="-"$flag
        if [ "$argval" == "$sflag" ]
        then
            declare $flag=$2
            match=1
        fi
    done
        if [ "$match" == "1" ]
    then
        shift 2
    else
        leftovers=$(echo $leftovers $argval)
        shift
    fi
    count=$(($count+1))
done

#Cleanup then restore the leftovers
echo "pre final clear args:
$@"
shift $#
echo "post final clear args:
$@"
set -- $leftovers
echo "all post set args:
$@"
echo arg1: $1 arg2: $2

echo leftovers: $leftovers
echo rate $rate time $time number $number

最后一个,如果传递了一个无效的参数,这一个会出错。

#!/usr/bin/env bash
#shebang.io
rate=30
time=30
number=30
validflags="rate time number"
count=1
for arg in $@
do
    argval=$1
    match=0
        if [ "${argval:0:1}" == "-" ]
    then
        for flag in $validflags
        do
                sflag="-"$flag
            if [ "$argval" == "$sflag" ]
            then
                declare $flag=$2
                match=1
            fi
        done
        if [ "$match" == "0" ]
        then
            echo "Bad argument: $argval"
            exit 1
        fi
        shift 2
    else
        leftovers=$(echo $leftovers $argval)
        shift
    fi
    count=$(($count+1))
done
#Cleanup then restore the leftovers
shift $#
set -- $leftovers
echo rate $rate time $time number $number
echo leftovers: $leftovers

优点:不管怎么说,它处理得很好。它保留了许多其他解决方案所没有的未使用的参数。它还允许调用变量,而无需在脚本中手动定义。如果没有给出相应的参数,它还允许预填充变量。(请参阅详细示例)。

缺点:无法解析单个复杂的arg字符串,例如-xcvf将作为单个参数处理。不过,您可以很容易地在我的代码中编写额外的代码,以添加此功能。

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

如果您正在制作可与其他实用程序互换的脚本,下面的灵活性可能很有用。

以下任一项:

command -x=myfilename.ext --another_switch 

Or:

command -x myfilename.ext --another_switch

代码如下:

STD_IN=0

prefix=""
key=""
value=""
for keyValue in "$@"
do
  case "${prefix}${keyValue}" in
    -i=*|--input_filename=*)  key="-i";     value="${keyValue#*=}";; 
    -ss=*|--seek_from=*)      key="-ss";    value="${keyValue#*=}";;
    -t=*|--play_seconds=*)    key="-t";     value="${keyValue#*=}";;
    -|--stdin)                key="-";      value=1;;
    *)                                      value=$keyValue;;
  esac
  case $key in
    -i) MOVIE=$(resolveMovie "${value}");  prefix=""; key="";;
    -ss) SEEK_FROM="${value}";          prefix=""; key="";;
    -t)  PLAY_SECONDS="${value}";           prefix=""; key="";;
    -)   STD_IN=${value};                   prefix=""; key="";; 
    *)   prefix="${keyValue}=";;
  esac
done

根据这里的其他答案,这是我的版本:

#!/bin/bash
set -e

function parse() {
    for arg in "$@"; do # transform long options to short ones
        shift
        case "$arg" in
            "--name") set -- "$@" "-n" ;;
            "--verbose") set -- "$@" "-v" ;;
            *) set -- "$@" "$arg"
        esac
    done

    while getopts "n:v" optname  # left to ":" are flags that expect a value, right to the ":" are flags that expect nothing
    do
        case "$optname" in
            "n") name=${OPTARG} ;;
            "v") verbose=true ;;
        esac
    done
    shift "$((OPTIND-1))" # shift out all the already processed options
}


parse "$@"
echo "hello $name"
if [ ! -z $verbose ]; then echo 'nice to meet you!'; fi

用法:

$ ./parse.sh
hello
$ ./parse.sh -n YOUR_NAME
hello YOUR_NAME
$ ./parse.sh -n YOUR_NAME -v
hello YOUR_NAME
nice to meet you!
$ ./parse.sh -v -n YOUR_NAME
hello YOUR_NAME
nice to meet you!
$ ./parse.sh -v
hello 
nice to meet you!

这里有一个getopts,它用最少的代码实现解析,并允许您在一种情况下使用eval和substring定义要提取的内容。

基本上eval“local key='val'”

function myrsync() {

        local backup=("${@}") args=(); while [[ $# -gt 0 ]]; do k="$1";
                case "$k" in
                    ---sourceuser|---sourceurl|---targetuser|---targeturl|---file|---exclude|---include)
                        eval "local ${k:3}='${2}'"; shift; shift    # Past two arguments
                    ;;
                    *)  # Unknown option  
                        args+=("$1"); shift;                        # Past argument only
                    ;;                                              
                esac                                                
        done; set -- "${backup[@]}"                                 # Restore $@


        echo "${sourceurl}"
}

在这里,将变量声明为局部变量,而不是全局变量。

调用为:

myrsync ---sourceurl http://abc.def.g ---sourceuser myuser ... 

${k:3}基本上是一个从键中删除第一个---的子字符串。