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Fabric-ThreadingGroup异常是否停止其余请求?

fabric python-2.7 python

Brad Parks · 技术社区 · 7 年前

我是Fabric新手,希望对一些远程SSH服务器并行执行一系列命令。

似乎我应该使用ThreadingGroup来完成这项工作,我可以做到,而且似乎很有效。

我唯一真正的问题是,我想了解如何处理错误情况,以及如何以字符串形式传入服务器列表,这是我从文件或命令行获得的。

我该怎么做?

1 回复 | 直到 7 年前

Community Mohan Dere 6 年前

我发现 an example in a github issue ,并将其扩展到适用于我的用例。。。希望有帮助!

test.py

# requires fabric 2.x - run 'pip install fabric' to install it
import logging, socket, paramiko.ssh_exception
from fabric import Connection, Config, SerialGroup, ThreadingGroup, exceptions, runners
from fabric.exceptions import GroupException

# Note: You need to supply your own valid servers here to ssh to of course!
def main():
    testHosts("All should succeed", "validServer1,validServer2,validServer3")
    testHosts("Some should fail", "validServer1,validServer2,BADSERVER1,validServer3,BADSERVER2")

def testHosts(message, hostsAsString):
    print("")
    print(message)

    # Get list of hosts from somewhere, and convert them to connections
    hosts = hostsAsString.split(",")
    servers = [Connection(host=host) for host in hosts]
        
    # Create a thread group to run requests in parallel
    g = ThreadingGroup.from_connections(servers)
    try:
        command = "df -h / | tail -n1 | awk '{print $5}'"
        results = g.run(command, hide=True)
        for r in results:
            connection = results[r]
            print("{}".format(r.host) )
            print("  SUCCESS, " + connection.stdout.strip())
    except GroupException as e:
        # If an exception occurred, at least one request failed. 
        # Iterate through results here
        for c, r in e.result.items():
            print("{}".format(c.host) )
            if isinstance(r,runners.Result) :
                print("  SUCCESS, " + r.stdout.strip())
            elif isinstance(r,socket.gaierror) :
                print("  FAILED,  Network error")
            elif isinstance(r,paramiko.ssh_exception.AuthenticationException) :
                print("  FAILED,  Auth failed")
            else:
                print("  FAILED,  Something other reason")

main()

这将产生以下输出

$ python test.py

All should succeed
validServer1
  SUCCESS, 59%
validServer2
  SUCCESS, 54%
validServer3
  SUCCESS, 53%

Some should fail
validServer1
  SUCCESS, 59%
validServer2
  SUCCESS, 54%
validServer3
  SUCCESS, 53%
BADSERVER1
  FAILED,  Network error
BADSERVER2
  FAILED,  Network error

Issa Daniel 6 年前

因此,如果: 2.2.2.2已关闭

“2.2.2.2,1.1.1.1”将起作用,但也将通过屏幕上的错误来实现。