根据作者名称生成唯一ID
根据合作关系生成图

import xml.sax
class authorHandler(xml.sax.ContentHandler):   #extract all authors
    def __init__(self):
        self.CurrentData=""     #tag's name
        self.dict={}   #save all authors. The key is an author's name, the value is his id
        self.name=""   #the name of an author
        self.id=0      #the ID of an author
    def startElement(self, tag, attributes):   
        self.CurrentData = tag
        self.name = ""

    def endElement(self, tag):
        if self.CurrentData == 'author':    #this tag is author, save it in the dict
            exist = self.dict.get(self.name, -1)    
            if exist == -1:     #if this author have not been added into dict
                self.dict[self.name] = self.id
                self.id = self.id + 1
                self.name=""
        print(self.id)

    def characters(self, content):
        if self.CurrentData == 'author':
            self.name += content


class collabrationHandler(xml.sax.ContentHandler):    #extract all collaboration relations
    def __init__(self, dict, file):
        self.CurrentData=""     #tag's name
        self.dict = dict   #the author-ID dict
        self.name=""   #the name of an author
        self.id=0      #the ID of an author
        self.paper=False   #if the tag is article or inproceeding, paper = True
        self.author=[]  #all authors' id in one <article> or <inproceeding>
        self.file = file   #Output collaboration relation to file
        self.edge = set()   #Edge's set
    def startElement(self, tag, attributes):   
        self.CurrentData = tag
        if tag == 'article' or tag == 'inproceeding':
            self.author.clear()   #start processing a new paper, old collaboration neen to be deleted
            self.paper = True

    def endElement(self, tag):
        if (tag == 'article' or tag == 'inproceeding') and self.paper == True:   #One paper's tag close
            self.paper = False
            for i in self.author:
                for j in self.author:
                    if i < j and (i,j) not in self.edge:    #edge
                        self.file.write(str(i) + ' ' + str(j) + '\n')
                        self.edge.add((i,j))

    def characters(self, content):
        if self.paper == True:
            self.name = content
            isAuthor = self.dict.get(self.name, -1)   # isAuthor == -1 means that this content is not an author's name
            if isAuthor != -1:
                self.author.append(self.dict[self.name])    #add this author's id 

#set xml parser
parser = xml.sax.make_parser()
parser.setFeature(xml.sax.handler.feature_namespaces, 0)
handler1 = authorHandler()
parser.setContentHandler(handler1)
parser.parse('/Users/zh/Documents/data/dblp.xml')

with open('author.txt','w') as f:
    for k,v in handler1.dict.items():
        f.write(str(v))
        f.write(' '+k)
        f.write('\n')
f.close()


with open('collaboration.txt', 'w') as f:
    handler2 = collabrationHandler(handler1.dict, f)
    parser.setContentHandler(handler2)
    parser.parse('/Users/zh/Documents/data/dblp.xml')
f.close()