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。列表，即 parseOutput() 的内容，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，出现以下错误：

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。文档没有说明太多，所有在线示例似乎都是用与我的代码相同的语法编写的。

Answer 1

您看到的问题是由

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

这导致parsePcap()在len(pkts)小于 20时返回一个带有空列表或列表末尾的序列列表：

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 时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，您会发现它告诉您n有 0 个要解包的值。如果n节点是一个空列表，这是有道理的：

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以下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

这更容易且更易读，因为您不需要大惊小怪的索引号和递增计数器变量。此外，它允许您处理任意数量的项目，pkts而无需首先知道 pkts.

需要修复的另一件事是nodeList通常与edgeList.

如果要声明 a nodeList，则nodeList应该是可迭代的 IP 地址，而 edgeList 应该是可迭代的元组，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并使用

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()

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