为Pysnmp get_request使用nameko创建服务时出错--尝试对ASN.1架构对象执行"nameko_entrypoints“操作

Question

我刚接触pysnmp和nameko。我被分配了一项工作，在nameko框架中创建一个服务，以便使用get_request库执行snmp。

下面是我尝试过的代码

from pysnmp.hlapi import *
from nameko.rpc import rpc


class GreetingService(object):
    name = "greeting_service"

    @rpc
    def getFunc(oid):
        errorIndication, errorStatus, errorIndex, varBinds = next(
            getCmd(SnmpEngine(),
                   CommunityData('public', mpModel=0),
                   UdpTransportTarget(('snmp.live.gambitcommunications.com', 161)),
                   ContextData(),
                   ObjectType(ObjectIdentity('SNMPv2-MIB', oid, 0)))
        )

        if errorIndication:
            print(errorIndication)
        elif errorStatus:
            print('%s at %s' % (errorStatus.prettyPrint(),
                                errorIndex and varBinds[int(errorIndex) - 1][0] or '?'))
        else:
            for varBind in varBinds:
                print(' = '.join([x.prettyPrint() for x in varBind]))

    if __name__ == "__main__":
        getFunc('sysName')

当我尝试通过以下命令使用终端启动服务时

$ nameko run helloworld

我得到以下错误消息。

syed@syed-ThinkPad-E480:~/Pysnmp$ nameko run helloworld
Traceback (most recent call last):
  File "/home/syed/.local/bin/nameko", line 11, in <module>
    sys.exit(main())
  File "/home/syed/.local/lib/python3.7/site-packages/nameko/cli/main.py", line 112, in main
    args.main(args)
  File "/home/syed/.local/lib/python3.7/site-packages/nameko/cli/commands.py", line 110, in main
    main(args)
  File "/home/syed/.local/lib/python3.7/site-packages/nameko/cli/run.py", line 181, in main
    import_service(path)
  File "/home/syed/.local/lib/python3.7/site-packages/nameko/cli/run.py", line 71, in import_service
    if inspect.getmembers(potential_service, is_entrypoint):
  File "/usr/lib/python3.7/inspect.py", line 354, in getmembers
    if not predicate or predicate(value):
  File "/home/syed/.local/lib/python3.7/site-packages/nameko/cli/run.py", line 35, in is_entrypoint
    return hasattr(method, ENTRYPOINT_EXTENSIONS_ATTR)
  File "/home/syed/.local/lib/python3.7/site-packages/pyasn1/type/base.py", line 221, in __getattr__
    raise error.PyAsn1Error('Attempted "%s" operation on ASN.1 schema object' % attr)
pyasn1.error.PyAsn1Error: Attempted "nameko_entrypoints" operation on ASN.1 schema object
Error in sys.excepthook:
Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/apport_python_hook.py", line 63, in apport_excepthook
    from apport.fileutils import likely_packaged, get_recent_crashes
  File "/usr/lib/python3/dist-packages/apport/__init__.py", line 5, in <module>
    from apport.report import Report
  File "/usr/lib/python3/dist-packages/apport/report.py", line 30, in <module>
    import apport.fileutils
  File "/usr/lib/python3/dist-packages/apport/fileutils.py", line 23, in <module>
    from apport.packaging_impl import impl as packaging
  File "/usr/lib/python3/dist-packages/apport/packaging_impl.py", line 24, in <module>
    import apt
  File "/usr/lib/python3/dist-packages/apt/__init__.py", line 23, in <module>
    import apt_pkg
ModuleNotFoundError: No module named 'apt_pkg'

Original exception was:
Traceback (most recent call last):
  File "/home/syed/.local/bin/nameko", line 11, in <module>
    sys.exit(main())
  File "/home/syed/.local/lib/python3.7/site-packages/nameko/cli/main.py", line 112, in main
    args.main(args)
  File "/home/syed/.local/lib/python3.7/site-packages/nameko/cli/commands.py", line 110, in main
    main(args)
  File "/home/syed/.local/lib/python3.7/site-packages/nameko/cli/run.py", line 181, in main
    import_service(path)
  File "/home/syed/.local/lib/python3.7/site-packages/nameko/cli/run.py", line 71, in import_service
    if inspect.getmembers(potential_service, is_entrypoint):
  File "/usr/lib/python3.7/inspect.py", line 354, in getmembers
    if not predicate or predicate(value):
  File "/home/syed/.local/lib/python3.7/site-packages/nameko/cli/run.py", line 35, in is_entrypoint
    return hasattr(method, ENTRYPOINT_EXTENSIONS_ATTR)
  File "/home/syed/.local/lib/python3.7/site-packages/pyasn1/type/base.py", line 221, in __getattr__
    raise error.PyAsn1Error('Attempted "%s" operation on ASN.1 schema object' % attr)
pyasn1.error.PyAsn1Error: Attempted "nameko_entrypoints" operation on ASN.1 schema object

请帮助我了解我所尝试的是正确的方式还是错误的方式。如果是这样，如何纠正错误。

任何帮助都是值得欣赏的。

提前感谢

Answer 1

这与nameko连接你的代码的方式有关。

它似乎尝试在您模块中找到的所有对象中查找nameko_entrypoints属性，最终运行到ASN.1schema对象中(这些对象是神圣的，不应用于除蓝图之外的任何用途)。

我的建议是将from pysnmp.hlapi import *替换为您在代码中使用的pysnmp类/函数的特定导入。希望能把易碎的碎片藏在nameko的视线之外。