Bash脚本带-d标志可下载 无标志时无法上传的问题求助

问题描述 #

编写了一款基于transfer.sh的Bash脚本，核心功能为文件上传、下载：

• 使用-d标志时可下载文件，示例命令：./script -d ./tests HJkv1I test.txt，此功能正常
• 不使用标志时应执行上传，示例命令：./script test.txt test1.txt，但此场景下脚本无任何反应

原脚本代码：

#!/bin/bash

fileUpload() {
  local filepath=$1
  local transfer_path=$2
  local url

  url=$(curl --progress-bar --upload-file "$filepath" "https://transfer.sh/$transfer_path")

  echo "$url"
}

printOutUpload() {
  local filepath=$1
  local url

  echo "Uploading $filepath"

  url=$(fileUpload "$filepath")

  echo "Transfer File URL: $url"
}

fileDownload() {
  local destination=$1
  local url=$2
  local file_name=$3

  curl -# "https://transfer.sh/$url/$file_name" -o "$destination/$file_name"
}

printOutDownload() {
  if [ $? -eq 0 ]; then
    echo "Success!"
  else
    echo "Error: There was a problem downloading the file."
  fi
}

while getopts "d:" opt; do
  case $opt in
    d)
      printOutDownload
      fileDownload "$2" "$3" "$4"
      ;;
    \?)
      echo "Invalid option: -$OPTARG" >&2
      exit 1
      ;;
  esac
done

问题原因 #

1. 缺少无选项分支逻辑：脚本仅处理了带-d的情况，当没有任何命令行选项时，while getopts循环直接跳过，未执行任何上传相关代码
2. 上传函数参数传递错误：printOutUpload调用fileUpload时只传了1个参数，但fileUpload需要2个参数（本地文件路径、transfer.sh上的目标路径）
3. 下载逻辑参数传递错误：getopts中-d分支里使用$2、$3、$4获取参数不可靠，且printOutDownload调用时机错误（在fileDownload之前，导致$?无法获取curl的执行状态）

修复后的脚本 #

#!/bin/bash

fileUpload() {
  local filepath=$1
  local transfer_path=$2
  local url

  url=$(curl --progress-bar --upload-file "$filepath" "https://transfer.sh/$transfer_path")

  echo "$url"
}

printOutUpload() {
  local filepath=$1
  local transfer_path=$2
  local url

  echo "Uploading $filepath"

  url=$(fileUpload "$filepath" "$transfer_path")

  echo "Transfer File URL: $url"
}

fileDownload() {
  local destination=$1
  local url=$2
  local file_name=$3

  curl -# "https://transfer.sh/$url/$file_name" -o "$destination/$file_name"
}

printOutDownload() {
  if [ $? -eq 0 ]; then
    echo "Success!"
  else
    echo "Error: There was a problem downloading the file."
  fi
}

# 处理命令行选项
while getopts "d" opt; do
  case $opt in
    d)
      # 移除已处理的选项，剩余参数为下载所需的目标路径、URL段、文件名
      shift $((OPTIND - 1))
      if [ $# -ne 3 ]; then
        echo "Usage for download: $0 -d <destination> <transfer-url-segment> <filename>" >&2
        exit 1
      fi
      fileDownload "$1" "$2" "$3"
      printOutDownload
      exit 0
      ;;
    \?)
      echo "Invalid option: -$OPTARG" >&2
      exit 1
      ;;
  esac
done

# 处理无选项的上传逻辑
shift $((OPTIND - 1))
if [ $# -ne 2 ]; then
  echo "Usage for upload: $0 <local-filepath> <transfer-path>" >&2
  exit 1
fi

printOutUpload "$1" "$2"

关键修改点 #

• 添加无选项时的上传分支：在getopts循环结束后，检查剩余参数并执行上传逻辑
• 修复printOutUpload的参数传递：将第二个参数（transfer_path）传递给fileUpload
• 修复下载参数处理：使用shift $((OPTIND - 1))获取剩余参数，确保参数传递准确，并将printOutDownload移至fileDownload之后调用
• 添加参数数量检查：避免用户传入参数不足时脚本异常

内容的提问来源于stack exchange，提问作者Art