从AWS Lambda调用AWS EC2中的Flask端点时出错

Question

摘要

我有一个用gunicorn旋转的flask服务器，该服务器创建了一个我想从AWS lambda函数调用的端点。但是，当我在Lambda中运行测试时，它返回

  "errorMessage": "HTTPConnectionPool(host='<ip_of_ec2>', port=8000): Max retries exceeded with url: /api/v1/my_project(Caused by NewConnectionError('<urllib3.connection.HTTPConnection object at 0x7efec823ed60>: Failed to establish a new connection: [Errno 111] Connection refused'))",
  "errorType": "ConnectionError",
  "stackTrace": [
    "  File \"/var/lang/lib/python3.8/imp.py\", line 234, in load_module\n    return load_source(name, filename, file)\n",
...
    "  File \"/var/task/requests/adapters.py\", line 516, in send\n    raise ConnectionError(e, request=request)\n"
  ]
}

我需要在AWS中进行什么样的配置才能允许此调用，或者我缺少什么才能使lambda函数建立此连接。

我有什么

不用说，一切都在本地工作（我可以运行curl来调用EC2上的端点并建立连接）。 Lambda和EC2位于同一vpc上，以防万一安全组接受所有出站和入站流量。

Lambda函数

import requests

print('Loading function')
url = 'http://<ip_of_ec2>:8000/api/v1/my_project'


def respond(err, res=None):

    return {
        'statusCode': '400' if err else res.status_code,
        'body': err.message if err else res.json(),
        'headers': {
            'Content-Type': 'application/json',
        },
    }

def call_project(claim, link):
    return requests.post(url=url, json={"claim": claim, "link": link})


def lambda_handler(event, context):

    operations = {
        'POST': lambda x: call_project(**x)
    }

    operation = event['httpMethod']
    if operation in operations:
        payload = event['queryStringParameters'] if operation == 'GET' else json.loads(event['body'])
        return respond(None, operations[operation](payload))
    else:
        return respond(ValueError('Unsupported method "{}"'.format(operation)))

烧瓶端点

@app.route('/api/v1/my_project', methods=['GET', 'POST'])
def my_project():
    content = request.get_json()
  ...
    return jsonify(full_pre_json)

Gunicorn配置

bind = "0.0.0.0:8000"
workers = 1

timeout = 3 * 60  # 3 minutes

Answer 1

尝试将AWS Lambda配置为具有执行角色，以便与同一VPC中的aws资源进行交互。

执行角色：https://docs.aws.amazon.com/lambda/latest/dg/lambda-intro-execution-role.html

教程：https://docs.aws.amazon.com/lambda/latest/dg/services-rds-tutorial.html