无法使用本地设置中的 Python 代码触发 Lambda 函数

Question

我正在尝试使用Python代码触发Lambda函数，如下所示

import boto3
from botocore.exceptions import NoCredentialsError, PartialCredentialsError

def get_lambda_client():
    return boto3.client('lambda')

def invoke_lambda():
    lambda_client = get_lambda_client()
    if lambda_client:
       try:
           response = lambda_client.invoke(
               FunctionName='MyLambdaFunctionName',
               InvocationType='RequestResponse',  # or 'event for async invocation'
               Payload=b'{}' #Not sending any payload
           )
           print(f" the response from the aws = {response}")
       except Exception as e:
           print(f" Error invoking Lambda function: {e}")

invoke_lambda()

角色附加以下政策

1. 触发 Lambda 函数的策略

    {
      "Version": "2012-10-17",
      "Statement": [
        {
            "Effect": "Allow",
            "Action": "lambda:InvokeFunction",
            "Resource": "< arn of my lambda function>"
        },
        {
            "Effect": "Allow",
            "Action": "sts:AssumeRole",
            "Resource": "< arn of the role I created for lambda function which intern 
             will trigger aws step function>"
      }
     ]
   }
   

2. 我为此 Lambda 函数触发器创建的角色的可信策略

       {
         "Version": "2012-10-17",
         "Statement": [
            {
             "Effect": "Allow",
             "Principal": {
                 "Service": "lambda.amazonaws.com",
                 "AWS": "<arn for the iam user>"
                 },
             "Action": "sts:AssumeRole"
            }
          ]
        }
   

如果这里缺少任何内容，请告诉我。当我尝试从 python 代码触发 lambda 函数时遇到的错误是

Error invoking Lambda function: An error occurred (ExpiredTokenException) when calling the Invoke operation: The security token included in the request is expired

通过承担 sts 角色，提出可以在此处使用的解决方案。考虑到我没有权限获取

AccessKey

、

SecreteKey

和

SessionToken

。

Answer 1

当您执行

boto3.client('lambda')

时，您正在从环境变量 AWS_SESSION_TOKEN 或 ~/.aws/credentials 文件中检索凭证

您的会话令牌看起来已过期，您需要使用 sts 重新生成一个新令牌

boto3.client('sts').get_session_token()

请参阅 boto3 doc