通过networkx和使用python在图中添加节点和边

Question

我需要创建一个 IP 地址图并标记它们之间的边，我为此编写了下面的代码。 parseOutput() 的内容列表看起来像这样：

('172.16.254.128', '216.58.208.206')
('216.58.208.206', '172.16.254.128')
('172.16.254.128', '216.58.208.226')
('216.58.208.226', '172.16.254.128')
('172.16.254.128', '8.8.8.8')
('8.8.8.8', '172.16.254.128')
('172.16.254.128', '216.58.208.227')
('172.16.254.128', '216.58.208.227')
('216.58.208.227', '172.16.254.128')
('172.16.254.128', '216.58.208.227')
('172.16.254.128', '216.58.208.227')
...

当我运行此代码时，我收到以下错误：

Traceback (most recent call last):
  File "test.py", line 40, in <module>
    g.add_nodes_from(nodeList)
  File "/usr/local/lib/python2.7/dist-packages/networkx/classes/graph.py", line 429, in add_nodes_from
    nn,ndict = n
ValueError: need more than 0 values to unpack

---

import logging, sys, struct, binascii, socket
from scapy.all import *
import networkx as nx
import matplotlib.pyplot as plt

pkts=rdpcap("pcapFile.pcap",20)

def parsePcap():
        IPList = [[] for i in range (20)]
        count = 0
        for pkt in pkts:
                #print pkt.summary()
                if pkt.haslayer(IP):
                        #proto = pkt.getLayer(IP).proto
                        x = pkt.getlayer(IP).src
                        y = pkt.getlayer(IP).dst
                        IPList[count]= (x,y)
                        #IPList[count].append(proto)
                        print IPList[count]
                        count += 1
        return IPList


parseOutput = parsePcap()
nodeList = parseOutput
edgeList = parseOutput

g = nx.Graph()

g.add_nodes_from(nodeList)
print g.number_of_nodes
g.add_edges_from(edgeList)

pos = nx.spring_layout(g,scale=1) #default to scale=1
nx.draw(g,pos)

我什至不知道我做错了什么。文档并没有说明太多，而且 网上所有的例子似乎都是用和我的代码一样的语法编写的。

Answer 1

你看到的问题是由

引起的

IPList = [[] for i in range (20)]

当len(pkts) 小于 20 时，这会导致 parsePcap() 返回一个带有空列表或末尾的列表的序列列表：

parseOutput = [
('172.16.254.128', '216.58.208.206'),
...
('172.16.254.128', '216.58.208.227'),
[],  #<---------------- This is causing the problem 
]

当parseOutput 传递给g.add_nodes_from， 您会收到回溯错误消息：

File "/usr/local/lib/python2.7/dist-packages/networkx/classes/graph.py", line 429, in add_nodes_from
  nn,ndict = n
ValueError: need more than 0 values to unpack

回想起来，如果您仔细考虑错误消息 你可以看到它告诉你 n 有 0 个值需要解压。这使得 判断节点 n 是否为空列表：

In [136]: nn, ndict = []
ValueError: need more than 0 values to unpack

空列表来自parseOutput。

---

而不是预先分配一个固定大小的列表：

IPList = [[] for i in range (20)]

在 Python 中执行此操作的首选方法是使用 append 方法：

def parsePcap():
    IPList = []
    for pkt in pkts:
        if pkt.haslayer(IP):
            x = pkt.getlayer(IP).src
            y = pkt.getlayer(IP).dst
            IPList.append((x, y))
    return IPList

这更容易，更易读，因为你不需要对索引大惊小怪 数字并增加一个计数器变量。此外，它允许您处理 pkts 中任意数量的项目，而无需首先知道 pkts.

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需要修复的另一件事是nodeList 通常不是 与edgeList 相同。

如果您要声明nodeList， nodeList 应该是 IP 地址的可迭代对象，而 edgeList 应该是元组的可迭代对象，例如 parseOutput:

nodeList = set([item for pair in parseOutput for item in pair])
print(nodeList)
# set(['216.58.208.206', '216.58.208.227', '172.16.254.128',
#  '216.58.208.226', '8.8.8.8'])

但是，由于 edgeList 中也提到了所有节点，因此您可以省略声明节点而直接使用

edgeList = parseOutput
g.add_edges_from(edgeList)

g.add_edges_from 将隐式添加节点。

---

import matplotlib.pyplot as plt
import networkx as nx

parseOutput = [
('172.16.254.128', '216.58.208.206'),
('216.58.208.206', '172.16.254.128'),
('172.16.254.128', '216.58.208.226'),
('216.58.208.226', '172.16.254.128'),
('172.16.254.128', '8.8.8.8'),
('8.8.8.8', '172.16.254.128'),
('172.16.254.128', '216.58.208.227'),
('172.16.254.128', '216.58.208.227'),
('216.58.208.227', '172.16.254.128'),
('172.16.254.128', '216.58.208.227'),
('172.16.254.128', '216.58.208.227'),]

g = nx.Graph()
edgeList = parseOutput
g.add_edges_from(edgeList)

pos = nx.spring_layout(g,scale=1) #default to scale=1
nx.draw(g,pos, with_labels=True)
plt.show()

产量

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