Changeset - 44cf81f3b6b8
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Laman - 8 years ago 2017-10-01 20:35:44

server can also serve data blocks
1 file changed with 23 insertions and 10 deletions:
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src/server.py
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@@ -32,79 +32,92 @@ class Server:
 
		if treeFile:
 
			self._tree=HashTree.load(treeFile)
 
		else:
 
			self._tree=HashTree.fromFile(filename)
 

	
 
		self._newLeaves=dict()
 
		self.BLOCK_SIZE=self._tree.BLOCK_SIZE
 

	
 
		self._ss = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
 
		self._ss.bind(("", conf.port))
 
		self._ss.listen(1)
 

	
 
		self._lastWrite=-1
 
		self._lastIndex=-1
 
		self._dataFile=None
 

	
 
	def serve(self):
 
		while True:
 
			with Connection(self._ss) as (incoming, outcoming):
 
				try:
 
					while True:
 
						if not self._serveOne(incoming,outcoming): return
 
				except AssertionError:
 
					continue
 

	
 
	def _serveOne(self,incoming,outcoming):
 
		jsonData,binData=incoming.readMsg()
 

	
 
		if jsonData["command"]=="init":
 
			assert jsonData["blockSize"]==self.BLOCK_SIZE
 
			assert jsonData["blockCount"]==self._tree.leafCount
 
			outcoming.writeMsg({"command": "ack"})
 

	
 
		elif jsonData["command"]=="req":
 
			outcoming.writeMsg(*self._requestHash(jsonData))
 
			if jsonData["dataType"]=="data":
 
				outcoming.writeMsg(*self._requestData(jsonData["index"]))
 
			else:
 
				outcoming.writeMsg(*self._requestHash(jsonData["index"]))
 

	
 
		elif jsonData["command"]=="send" and jsonData["dataType"]=="data":
 
			outcoming.writeMsg(*self._receiveData(jsonData,binData))
 

	
 
		elif jsonData["command"]=="end":
 
			self._finalize()
 
			return False
 

	
 
		else:
 
			assert False, jsonData["command"]
 

	
 
		return True
 

	
 
	def _requestHash(self,jsonData):
 
		log.info("received request for node #{0}".format(jsonData["index"]))
 
		assert jsonData["index"]<len(self._tree.store)
 
		nodeHash=self._tree.store[jsonData["index"]]
 
	def _requestHash(self,index):
 
		log.info("received request for node #{0}".format(index))
 
		assert index<len(self._tree.store)
 
		nodeHash=self._tree.store[index]
 

	
 
		jsonResponse={"command":"send", "index":index, "dataType":"hash"}
 
		binResponse=nodeHash
 

	
 
		jsonResponse={"command":"send", "index":jsonData["index"], "dataType":"hash"}
 
		binResponse=nodeHash
 
		return (jsonResponse,binResponse)
 

	
 
	def _requestData(self,index):
 
		log.info("received request for data block #{0}".format(index))
 

	
 
		jsonResponse={"command":"send", "index":index, "dataType":"data"}
 
		if self._lastIndex+1!=index:
 
			self._dataFile.seek(index*self.BLOCK_SIZE)
 
		binResponse=self._dataFile.read(self.BLOCK_SIZE)
 

	
 
		return (jsonResponse,binResponse)
 

	
 
	def _receiveData(self,jsonData,binData):
 
		log.info("received data block #{0}: {1}...{2}".format(jsonData["index"],binData[:5],binData[-5:]))
 

	
 
		if not self._dataFile:
 
			self._dataFile=open(self._filename, mode="rb+")
 
		i=jsonData["index"]
 
		if self._lastWrite+1!=i:
 
		if self._lastIndex+1!=i:
 
			self._dataFile.seek(i * self.BLOCK_SIZE)
 
		self._dataFile.write(binData)
 
		self._lastWrite=i
 
		self._lastIndex=i
 
		if self._treeFile:
 
			self._newLeaves[i + self._tree.leafStart]= hashlib.sha256(binData).digest()[HashTree.HASH_LEN:]
 

	
 
		return ({"command": "ack", "index": i},)
 

	
 
	def _finalize(self):
 
		log.info("closing session...")
 
		if self._dataFile:
 
			self._dataFile.close()
 
		if self._treeFile:
 
			log.info("updating hash tree...")
 
			for (k,v) in self._newLeaves.items():
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