在Bash脚本中设置AWS环境变量失效问题排查

我编写了一个带可选参数-p的Bash脚本，希望将指定AWS profile的配置导出为当前Shell的环境变量。通过source执行脚本后，提示默认配置已设置，但执行echo $AWS_ACCESS_KEY_ID时无输出，请问问题出在哪里？

脚本代码如下：

#!/bin/bash

# This script is used to set an AWS profile for the current shell session.
# It is intended to be used with the AWS CLI and the AWS CLI v2.

usage() { echo "Usage: $0 [-p <string>]"; exit 1; }

while getopts "p:" options; do
    case "${options}" in
        p)
            p=${OPTARG}
            ;;

    esac
done

if [ -z "${p}" ]; then
  export AWS_ACCESS_KEY_ID=$(aws configure get default.aws_access_key_id)
  export AWS_SECRET_ACCESS_KEY=$(aws configure get default.aws_secret_access_key)
  export AWS_DEFAULT_REGION=$(aws configure get default.region)
  echo "Default profile set"
else
  aws configure list-profiles | grep -q "${p}"
  if [ $? -ne 0 ]; then
    echo "Profile ${p} not found"
    exit 1
  else
    export AWS_ACCESS_KEY_ID=$(aws configure get "${p}".aws_access_key_id)
    export AWS_SECRET_ACCESS_KEY=$(aws configure get "${p}".aws_secret_access_key)
    export AWS_DEFAULT_REGION=$(aws configure get "${p}".region)
  fi
fi

执行命令及输出：

source ./set-aws-profile
# 输出：
Default profile set
% echo $AWS_ACCESS_KEY_ID    
# 无任何输出

• 核心问题：aws configure get命令参数格式错误
  你使用aws configure get default.aws_access_key_id的格式不符合AWS CLI规范，正确的写法应该是通过--profile参数指定profile，而非将profile名称拼接在配置项前。错误格式会导致命令返回空值，最终导出的环境变量为空，所以echo $AWS_ACCESS_KEY_ID无输出。

• 修复后的脚本关键调整
  将所有aws configure get命令的格式修正，默认profile可省略--profile参数，指定profile时添加该参数：

  if [ -z "${p}" ]; then
    export AWS_ACCESS_KEY_ID=$(aws configure get aws_access_key_id)
    export AWS_SECRET_ACCESS_KEY=$(aws configure get aws_secret_access_key)
    export AWS_DEFAULT_REGION=$(aws configure get region)
    echo "Default profile set"
  else
    aws configure list-profiles | grep -q "${p}"
    if [ $? -ne 0 ]; then
      echo "Profile ${p} not found"
      exit 1
    else
      export AWS_ACCESS_KEY_ID=$(aws configure get aws_access_key_id --profile "${p}")
      export AWS_SECRET_ACCESS_KEY=$(aws configure get aws_secret_access_key --profile "${p}")
      export AWS_DEFAULT_REGION=$(aws configure get region --profile "${p}")
    fi
  fi
  

• 额外优化建议

  • 可在导出变量前检查aws configure get的返回值，若为空则提示用户该profile配置项不完整，避免导出无效空变量。
  • 脚本开头增加aws命令存在性检查，防止因未安装AWS CLI导致的无意义错误。

内容的提问来源于stack exchange，提问作者A Simple Programmer