如何配置AWS lambda执行角色以列出批处理作业

Question

我有问题正确配置了我的lambda，以便能够运行批处理作业。代码看起来像这样：

client = boto3.client('batch')
_job_queue = os.environ['JOB_QUEUE']
_job_definition = os.environ['JOB_DEFINITION']
_job_name = os.environ['START_JOB_NAME']
def lambda_handler(event, context):
    return start_job()
def start_job():
    response = client.list_jobs(jobQueue=_job_queue)
    if _job_name in [job.jobName for job in response['jobSummaryList']]:
        return 200
    try:
        client.submit_job(jobName=_job_name, jobQueue=_job_queue, jobDefinition=_job_definition)
        return 201
    except:
        return 400

它在 client.list_jobs(Jobqueue = _job_queue(上失败，带有以下错误：

" errormessage"："发生错误(AccessDeniedException( 调用ListJobs操作：用户： ARN：AWS：STS :: 749340585813：假定的/myproject/dev-startjoblambda-hzo22z5imtfb 无权执行：批次：listJobs在资源上： ARN：AWS：批次：us-west-2：749340585813：/v1/listjobs"，

如果我将访问键添加到上面的lambda，则可以正常工作。我认为这是因为我具有管理员访问权限，并且在用户赋予Lambda我的特权时进行身份验证。

我的lambda定义看起来像：

"StartJobLambda": {
  "Type": "AWS::Lambda::Function",
  "Properties": {
    "Description": "Starts the My Project model training job.",
    "Role": {
      "Fn::GetAtt": [
        "StartJobRole",
        "Arn"
      ]
    },
    "Runtime": "python3.6",
    "Handler": {
      "Fn::Sub": "${StartJobModule}.lambda_handler"
    },
    "Tags": [
      {
        "Key": "environment",
        "Value": {
          "Ref": "Environment"
        }
      },
      {
        "Key": "project",
        "Value": "myproject"
      }
    ],
    "Environment": {
      "Variables": {
        "JOB_QUEUE": {
          "Ref": "JobQueue"
        },
        "JOB_DEFINITION": {
          "Ref": "TrainingJob"
        }
      }
    },
    "Code": {
      "S3Bucket": {
        "Ref": "CodeBucket"
      },
      "S3Key": {
        "Ref": "StartJobKey"
      }
    },
    "VpcConfig": {
      "SubnetIds": [
        {
          "Fn::ImportValue": {
            "Fn::Sub": "${NetworkStackNameParameter}-PrivateSubnet"
          }
        },
        {
          "Fn::ImportValue": {
            "Fn::Sub": "${NetworkStackNameParameter}-PrivateSubnet2"
          }
        }
      ],
      "SecurityGroupIds": [
        {
          "Fn::ImportValue": {
            "Fn::Sub": "${NetworkStackNameParameter}-TemplateSecurityGroup"
          }
        }
      ]
    }
  }
}

还创建了以下角色和策略：

"StartJobRole": {
  "Type": "AWS::IAM::Role",
  "Properties": {
    "RoleName": "myproject-start-job",
    "AssumeRolePolicyDocument": {
      "Version": "2012-10-17",
      "Statement": [
        {
          "Effect": "Allow",
          "Principal": {
            "Service": [
              "lambda.amazonaws.com"
            ]
          },
          "Action": [
            "sts:AssumeRole"
          ]
        }
      ]
    },
    "Path": "/"
  }
},
"StartJobBatchPolicy": {
  "Type": "AWS::IAM::Policy",
  "Properties": {
    "PolicyName": "start-job-batch-policy",
    "PolicyDocument": {
      "Version": "2012-10-17",
      "Statement": [
        {
          "Effect": "Allow",
          "Action": [
            "batch:ListJobs",
            "batch:SubmitJob"
          ],
          "Resource": [
            {
              "Ref": "JobQueue"
            }
          ]
        }
      ]
    },
    "Roles": [
      {
        "Ref": "StartJobRole"
      }
    ]
  }
}

此外，还有一个角色可以使lambda在VPC上运行：

"LambdaVPCExecutionRole": {
  "Type": "AWS::IAM::Role",
  "Properties": {
    "RoleName": "myproject-lambda-vpc-execution-role",
    "AssumeRolePolicyDocument": {
      "Version": "2012-10-17",
      "Statement": [
        {
          "Effect": "Allow",
          "Principal": {
            "Service": [
              "lambda.amazonaws.com"
            ]
          },
          "Action": [
            "sts:AssumeRole"
          ]
        }
      ]
    },
    "Path": "/"
  }
},
"LambdaVPCExecutionPolicy": {
  "Type": "AWS::IAM::Policy",
  "Properties": {
    "PolicyName": "lambda-vpc-execution-policy",
    "PolicyDocument": {
      "Version": "2012-10-17",
      "Statement": [
        {
          "Effect": "Allow",
          "Action": [
            "logs:CreateLogGroup",
            "logs:CreateLogStream",
            "logs:PutLogEvents"
          ],
          "Resource": "arn:aws:logs:*:*:*"
        },
        {
          "Effect": "Allow",
          "Action": [
            "ec2:CreateNetworkInterface",
            "ec2:DescribeNetworkInterfaces",
            "ec2:DeleteNetworkInterface"
          ],
          "Resource": "*"
        }
      ]
    },
    "Roles": [
      {
        "Ref": "LambdaVPCExecutionRole"
      },
      {
        "Ref": "StartJobRole"
      }
    ]
  }
},

Answer 1

这是云形式需要改进的东西。一些AWS服务不允许资源级别的权限，但尝试创建它们时，您的堆栈将成功！。对于IAM相关的问题，有时您需要进入控制台并验证您的政策不处于警告状态。AWS至少将标记试图在不允许使用的服务上应用资源级别权限的政策。

例如，对于DynamoDB，您必须授予所有表的访问权限。您不能限制或重新访问单个表。如果您尝试创建CloudFormation IAM策略，它将不会失败，但是您所需的效果将无法实现。