FileUpload: fileuploadfilter.py

# FileUploadFilter
#
# Author: Michal Zylinski, michal.zylinski@gmail.com
#
# Version: 1.0
#


from cherrypy.lib.filter.basefilter import BaseInputFilter 
import StringIO
import cgi
import guid

class FileUploadFilter(BaseInputFilter):
        def __init__(self, pParsingContext):
                """
                ParsingContext = [(method, param in method, directory)]
                """
                self.ParsingContext = pParsingContext
                self.FilteringEnabled = False
                self.UploadParam = None
                self.UploadDirectory = None

        def afterRequestHeader(self):
                URLPath = cpg.request.path
                Method = URLPath[URLPath.rfind('/')+1:]
                if Method in [Item[0] for Item in self.ParsingContext]:
                        cpg.request.parsePostData = False
                        self.UploadParam, self.UploadDirectory = [(Item[1], Item[2]) for Item in self.ParsingContext if Item[0] == Method][0]
                        self.FilteringEnabled = True
                else:
                        self.FilteringEnabled = False
                        self.UploadParam = None
                        self.UploadDirectory = None
                        
        def afterRequestBody(self):
                if self.FilteringEnabled is False: return
                # Read request body and put it in data
                len = int(cpg.request.headerMap.get("Content-Length","0"))
                if len: data = cpg.request.rfile.read(len)
                else: data=""
                newRfile = StringIO.StringIO(data)
                lowerHeaderMap = {}
                for key, value in cpg.request.headerMap.items():
                                lowerHeaderMap[key.lower()] = value
                forms = cgi.FieldStorage(fp = newRfile, headers = lowerHeaderMap, environ = {'REQUEST_METHOD':'POST'}, keep_blank_values = 1)
                for key in forms.keys():
                        valueList = forms[key]
                        if type(valueList) == type([]):
                                        cpg.request.paramMap[key] = []
                                        cpg.request.filenameMap[key] = []
                                        cpg.request.fileTypeMap[key] = []
                                        for item in valueList:
                                                        cpg.request.paramMap[key].append(item.value)
                                                        cpg.request.filenameMap[key].append(item.filename)
                                                        cpg.request.fileTypeMap[key].append(item.type)
                        else: #here comes file processing routine
                                if valueList.name == self.UploadParam:
                                        OriginalFileExtension = valueList.filename[valueList.filename.rfind('.'):]
                                        NewName = self.UploadDirectory+guid.generate()+OriginalFileExtension
                                        SaveFile = file(NewName, 'wb')          
                                        while 1:
                                                data = valueList.file.read(1024 * 8) # Read blocks of 8KB at a time
                                                if not data: break
                                                SaveFile.write(data)
                                        SaveFile.close()
                                        cpg.request.paramMap[key] = NewName
                                        cpg.request.filenameMap[key] = valueList.filename
                                        cpg.request.fileTypeMap[key] = valueList.type           
                                else:
                                        cpg.request.paramMap[key] = valueList.value
                                        cpg.request.filenameMap[key] = valueList.filename
                                        cpg.request.fileTypeMap[key] = valueList.type


if __name__ == '__main__':      
#running test                           
        from cherrypy import cpg
        class Test:
                TempDir = 'c:\\temp\\'
                UploadContext = [('processUpload', 'fileob', TempDir)]
                _cpFilterList = [FileUploadFilter(UploadContext)]
                
                @cpg.expose
                def index(self):
                        return """<HTML><BODY>
                        <FORM ACTION="processUpload" METHOD="POST" ENCTYPE="multipart/form-data">
                        <INPUT TYPE="file" name="fileob">
                        <INPUT TYPE="submit">
                        </FORM>
                        </BODY></HTML>
                        """
                        
                @cpg.expose
                def processUpload(self, fileob):
                        yield 'File Name: %s<br>' % cpg.request.filenameMap['fileob']
                        yield 'File Type: %s<br>' % cpg.request.fileTypeMap['fileob']
                        yield 'Stored as: %s' % fileob
                        
        cpg.root = Test()
        cpg.server.start()