AWS和Boto3的Python追溯和属性错误

Question

正在努力使此脚本在早期版本2的Python 3上运行，并且仍然出现一些回溯和属性错误。 下面是错误，下面是该脚本的当前状态：特别感谢@Madlania Kalunder对打印问题进行排序。 现在我知道事情已经结束，但需要一些帮助。

Traceback (most recent call last):
File "ec2-instances.py", line 97, in <module> sys.exit(main())
File "ec2-instances.py", line 78, in main hosts=(list_instances)(filter)
File "ec2-instances.py", line 18, in list_instances
name = (item for item in i.tags if item ["Key"] == "Name" ).next()
AttributeError: 'generator' object has no attribute 'next'

下面是代码。 很抱歉在这里格式化问题，在此先感谢您的帮助。

#!/usr/bin/env python
import boto3
import sys
import argparse
import paramiko


def list_instances(Filter):
   ec2 = boto3.resource('ec2')
   instances = ec2.instances.filter(Filters=Filter)
   (columns_format) = ("%-3s %-26s %-16s %-16s %-20s %-12s %-12s %-16s")
print ((columns_format) % ("num", "Name", "Public IP", "Private IP", "ID", "Type", "VPC", "Status"))
  num = 1
  hosts = [] 
  name = {}  
  for i in instances:
  try:
     name = (item for item in i.tags if item ["Key"] == "Name" ).next()
  except StopIteration:
     name['Value'] = ''

  print (columns_format) % (
                           num,
                           name['Value'], 
                           i.public_ip_address,
                           i.private_ip_address,
                           i.id,
                           i.instance_type,
                           i.vpc_id,
                           i.state['Name']
                         )
  num = num + 1
  item={'id': i.id, 'ip': i.public_ip_address, 'hostname': name ['Value'], 'status': i.state['Name'],}
  hosts.append(item)
  return hosts

  def execute_cmd(host,user,cmd):
  ssh = paramiko.SSHClient()
  ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
  try:
   ssh.connect(host, username=user)
   stdin, stdout, stderr = ssh.exec_command(cmd)
   stdout=stdout.read()
   stderr=stderr.read()
   ssh.close()
   return stdout,stderr
except paramiko.AuthenticationException as exception: 
   return "Authentication Error trying to connect into the host %s with the user %s. Plese review your keys" % (host, user), e 

 def main():
    parser = argparse.ArgumentParser()
    parser.add_argument('-n', '--name',
                    help="Filter result by name.")
    parser.add_argument('-t', '--type',
                    help="Filer result by type.")
    parser.add_argument('-s', '--status',
                    help="Filter result by status." )
    parser.add_argument('-e', '--execute',
                    help="Execute a command on instances")
    parser.add_argument('-u', '--user', default="ubuntu",
                    help="User to run commands if -e option is used.\
                          Ubuntu user is used by default")

arg = parser.parse_args()

# Default filter if no options are specified
filter=[]

if arg.name:
    filter.append({'Name': 'tag-value', 'Values': ["*" + arg.name + "*"]})

if arg.type:
    filter.append({'Name': 'instance-type', 'Values': ["*" + arg.type + "*"]})

if arg.status:
    filter.append({'Name': 'instance-state-name', 'Values': ["*" + arg.status + "*"]})

hosts=list_instances(filter)
names = ""

if arg.execute:
   for item in hosts:
      names = names + " " + item["hostname"] + "(" + item["id"] + ")"
   print ("\nCommand to execute: %s") % arg.execute
   print ("Executed by: %s") % arg.user
   print ("Hosts list: %s\n") % names 
   for item in hosts:
      if item["status"] == 'running':
         print ("::: %s (%s)") % (item["hostname"], item["id"])
         stdout,stderr = execute_cmd(item["ip"], arg.user, arg.execute)
         print (stdout) 
         print (stderr)
      else:
         print ("::: %s (%s) is not running (command execution skiped)") % (item["hostname"], item["id"])

if __name__ == '__main__':
sys.exit(main())

Answer 1

从同事那里得到了一些帮助，这是现在正确/工作的版本。 需要使用（）修复更多打印问题，以包括％并删除特定的例外规则。 还更正了.next以包括生成器。

#!/usr/bin/env python
import boto3
import sys
import argparse
import paramiko


def list_instances(Filter):
ec2 = boto3.resource('ec2')
instances = ec2.instances.filter(Filters=Filter)
(columns_format) = ("%-3s %-26s %-16s %-16s %-20s %-12s %-12s %-16s")
print ((columns_format) % ("num", "Name", "Public IP", "Private IP", "ID", "Type", "VPC", "Status"))
num = 1
hosts = [] 
name = {}  
for i in instances:
  try:
     name = next(item for item in i.tags if item["Key"] == "Name")
  except: 
     name['Value'] = ''

  print ((columns_format) % (
                           num,
                           name['Value'], 
                           i.public_ip_address,
                           i.private_ip_address,
                           i.id,
                           i.instance_type,
                           i.vpc_id,
                           i.state['Name']
                         ))
  num = num + 1
  item={'id': i.id, 'ip': i.public_ip_address, 'hostname': name ['Value'], 'status': i.state['Name'],}
  hosts.append(item)
return hosts

def execute_cmd(host,user,cmd):
ssh = paramiko.SSHClient()
ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
try:
   ssh.connect(host, username=user)
   stdin, stdout, stderr = ssh.exec_command(cmd)
   stdout=stdout.read()
   stderr=stderr.read()
   ssh.close()
   return stdout,stderr
except paramiko.AuthenticationException as exception: 
   return "Authentication Error trying to connect into the host %s with the user %s. Plese review your keys" % (host, user), e 

def main():
parser = argparse.ArgumentParser()
parser.add_argument('-n', '--name',
                    help="Filter result by name.")
parser.add_argument('-t', '--type',
                    help="Filer result by type.")
parser.add_argument('-s', '--status',
                    help="Filter result by status." )
parser.add_argument('-e', '--execute',
                    help="Execute a command on instances")
parser.add_argument('-u', '--user', default="ubuntu",
                    help="User to run commands if -e option is used.\
                          Ubuntu user is used by default")

arg = parser.parse_args()

# Default filter if no options are specified
filter=[]

if arg.name:
    filter.append({'Name': 'tag-value', 'Values': ["*" + arg.name + "*"]})

if arg.type:
    filter.append({'Name': 'instance-type', 'Values': ["*" + arg.type + "*"]})

if arg.status:
    filter.append({'Name': 'instance-state-name', 'Values': ["*" + arg.status + "*"]})

hosts=list_instances(filter)
names = ""

if arg.execute:
   for item in hosts:
      names = names + " " + item["hostname"] + "(" + item["id"] + ")"
   print (("\nCommand to execute: %s") % arg.execute)
   print (("Executed by: %s") % arg.user)
   print (("Hosts list: %s\n") % names) 
   for item in hosts:
      if item["status"] == 'running':
         print (("::: %s (%s)") % (item["hostname"], item["id"]))
         stdout,stderr = execute_cmd(item["ip"], arg.user, arg.execute)
         print (stdout) 
         print (stderr)
      else:
         print (("::: %s (%s) is not running (command execution skiped)") % (item["hostname"], item["id"]))

   if __name__ == '__main__':
sys.exit(main())