使用 AMI 备份脚本在 AWS Lambda 上将 python 2.7 更新到 3.8

Question

当我将 python 2.7 版本更新到 python 3.8 时，我的 AMI 脚本无法正常工作，在 lambda 部分下的 aws 控制台上测试代码后显示 2.7 版本和 3.8 版本之间的版本不匹配。谁能帮我解决这个问题？

谢谢

import boto3
import collections
import datetime
import time
import sys

ec2 = boto3.client('ec2')
sts = boto3.client('sts')
drec2 = boto3.client('ec2', region_name='eu-west-1')
dr = boto3.resource('ec2')
awsaccountid = sts.get_caller_identity().get('Account')
images = dr.images.filter(Owners=[awsaccountid])
date = datetime.datetime.now()
date_fmt = date.strftime('%Y-%m-%d')
time_fmt = date.strftime('%Y-%m-%d--%H-%M-%S')

def lambda_handler(event, context):

    def get_instance_name(itags):
        instancename = ''
        if itags is None:
            instancename = ''
        else:
            for tags in itags:
                if tags["Key"] == 'Name':
                    instancename = tags["Value"]
        return instancename

    # Check for the availability of the image
    def is_image_available(image_id):
        try:
            available = 0
            while available == 0:
                print("Not created yet.. Gonna sleep for 10 seconds")
                time.sleep(10)
                image = ec2.describe_images(ImageIds=[image_id])
                if image['Images'][0]['State'] == 'available':
                    available = 1
            if available == 1:
                print("Image is now available for use.")
            return True
        except Exception,e:
            print e

    reservations = ec2.describe_instances(
        Filters=[
            {'Name': 'tag:Backup', 'Values': ['yes', 'Yes']},
        ]
    ).get(
        'Reservations', []
    )

    instances = sum(
        [
            [i for i in r['Instances']]
            for r in reservations
            ], [])

    for instance in instances:
        try:
            retention_days = 2
        except IndexError:
            retention_days = 7
        finally:
            for image in images:
                #today_time = datetime.datetime.now().strftime('%m-%d-%Y')
                #today_fmt = today_time.strftime('%m-%d-%Y')
                #today_date = time.strptime(today_time, '%m-%d-%Y')
                aminame = get_instance_name(instance['Tags']) + "-" + instance['InstanceId'] + "-On-" + date_fmt
                if image.name == aminame:
                    if is_image_available(image.id):
                        dramiid = drec2.copy_image(SourceRegion='us-east-1', SourceImageId=image.id,
                                                          Name="DR-" + get_instance_name(instance['Tags']) + "-" +
                                                       `enter code here`        instance[
                                                                   'InstanceId'] + "-On-" + date_fmt,
                                                          Description="Lambda created AMI of instance " + instance[
                                                              'InstanceId'] + " On " + time_fmt)
                        print("Retaining DR AMI %s of instance %s for %d days" % (
                            dramiid['ImageId'],
                            instance['InstanceId'],
                            retention_days,
                        ))
                        # to_tag[retention_days].append(dramiid['ImageId'])
                        # for retention_days in to_tag.keys():
                        delete_date = datetime.date.today() + datetime.timedelta(days=retention_days)
                        delete_fmt = delete_date.strftime('%m-%d-%Y')
                        print("Will delete the DR AMI in %d days on %s" % (retention_days, delete_fmt))
                        # break
                        drec2.create_tags(
                            Resources=[dramiid['ImageId']],
                            Tags=[
                                {'Key': 'DeleteOn', 'Value': delete_fmt},
                            ]
                     )

出现以下错误：

Function Logs:

START 
RequestId: 1f9263c7-9736-4b31-934d-719d38f8fdba 
Version: $LATEST
[ERROR] Runtime.UserCodeSyntaxError: Syntax error in module 'lambda_function': invalid syntax (lambda_function.py, line 52) 
Traceback (most recent call last): File "/var/task/lambda_function.py"
Line 52 except Exception,e:END 
RequestId: 1f9263c7-9736-4b31-934d-719d38f8fdba

有人知道如何解决这个问题吗？

Answer 1

当你在 python3 中运行你的脚本时，你应该做一些语法改变。

例如

in python 3 , you say `print('value')` with brackets. 
in python 2, you say `print "hello"`

in python 3, you say `except Exception as e`
in python 2, you can say `except Exception, e`

这里：

import boto3
import collections
import datetime
import time
import sys

ec2 = boto3.client('ec2')
sts = boto3.client('sts')
drec2 = boto3.client('ec2', region_name='eu-west-1')
dr = boto3.resource('ec2')
awsaccountid = sts.get_caller_identity().get('Account')
images = dr.images.filter(Owners=[awsaccountid])
date = datetime.datetime.now()
date_fmt = date.strftime('%Y-%m-%d')
time_fmt = date.strftime('%Y-%m-%d--%H-%M-%S')

def lambda_handler(event, context):

    def get_instance_name(itags):
        instancename = ''
        if itags is None:
            instancename = ''
        else:
            for tags in itags:
                if tags["Key"] == 'Name':
                    instancename = tags["Value"]
        return instancename

    # Check for the availability of the image
    def is_image_available(image_id):
        try:
            available = 0
            while available == 0:
                print("Not created yet.. Gonna sleep for 10 seconds")
                time.sleep(10)
                image = ec2.describe_images(ImageIds=[image_id])
                if image['Images'][0]['State'] == 'available':
                    available = 1
            if available == 1:
                print("Image is now available for use.")
            return True
        except Exception as e:
            print(e)

    reservations = ec2.describe_instances(
        Filters=[
            {'Name': 'tag:Backup', 'Values': ['yes', 'Yes']},
        ]
    ).get(
        'Reservations', []
    )

    instances = sum(
        [
            [i for i in r['Instances']]
            for r in reservations
            ], [])

    for instance in instances:
        try:
            retention_days = 2
        except IndexError:
            retention_days = 7
        finally:
            for image in images:
                #today_time = datetime.datetime.now().strftime('%m-%d-%Y')
                #today_fmt = today_time.strftime('%m-%d-%Y')
                #today_date = time.strptime(today_time, '%m-%d-%Y')
                aminame = get_instance_name(instance['Tags']) + "-" + instance['InstanceId'] + "-On-" + date_fmt
                if image.name == aminame:
                    if is_image_available(image.id):
                        dramiid = drec2.copy_image(SourceRegion='us-east-1', SourceImageId=image.id,
                                                          Name="DR-" + get_instance_name(instance['Tags']) + "-" +
                                                       'enter code here' + instance[
                                                                   'InstanceId'] + "-On-" + date_fmt,
                                                          Description="Lambda created AMI of instance " + instance[
                                                              'InstanceId'] + " On " + time_fmt)
                        print("Retaining DR AMI %s of instance %s for %d days" % (
                            dramiid['ImageId'],
                            instance['InstanceId'],
                            retention_days,
                        ))
                        # to_tag[retention_days].append(dramiid['ImageId'])
                        # for retention_days in to_tag.keys():
                        delete_date = datetime.date.today() + datetime.timedelta(days=retention_days)
                        delete_fmt = delete_date.strftime('%m-%d-%Y')
                        print("Will delete the DR AMI in %d days on %s" % (retention_days, delete_fmt))
                        # break
                        drec2.create_tags(
                            Resources=[dramiid['ImageId']],
                            Tags=[
                                {'Key': 'DeleteOn', 'Value': delete_fmt},
                            ]
                     )