lays a egg

1 files changed, 286 insertions, 0 deletions

diff --git a/magicproxy/__init__.py b/magicproxy/__init__.py
new file mode 100755
index 0000000..5ab9773
--- /dev/null
+++ b/magicproxy/__init__.py
@@ -0,0 +1,286 @@
+#!/usr/bin/python -t
+import  os, sys, string, time, md5, random
+import asynchat, asyncore, socket, httplib, urlparse
+from heapq import heappush, heappop
+import cStringIO as StringIO
+
+kB = 1024
+
+class DefaultConfiguration:
+    """bind to that"""
+    listen=("",8080)
+
+    """available http-proxies"""
+    endpoints=[ ('10.2.2.11', 8888), ('10.3.1.2',8888) ]
+
+    """minimum entity size to start parallelize fetch"""
+    threshold = 512*kB
+    
+    """initial size/range for a fetcher-job"""
+    initial_blocksize=512*kB
+
+    """minimal size/range for a fetcher-job"""
+    minimal_blocksize=512*kB
+    
+    """(sec) #time each fetcher spent on his range,
+    calculated using speed measured while using initial_blocksize"""
+    time_slice=5
+
+    """start a new fetcher on a endpoint X-bytes before the old one finished"""
+    fetcher_jumpstart=32*kB
+        
+#################
+
+class Fetcher(asynchat.async_chat):
+    def __init__(self, reader, proxy, url, headers, range):
+        self.reader = reader
+        self.proxy = proxy
+        self.url = url
+        self.headers = headers
+        self.range = range
+
+        self.pos = (self.range[0] != -1) and self.range[0] or 0
+        self.start_time = 0
+        self.stop_time = 0
+        self.http_status = ""
+        self.http_header = StringIO.StringIO()
+        self.state = 0 #0=status, 1=header, 2=body
+        asynchat.async_chat.__init__(self)
+        self.set_terminator("\r\n")
+        self.create_socket(socket.AF_INET, socket.SOCK_STREAM)
+        self.connect(self.proxy)
+
+    def __str__(self):
+        return "<Fetcher proxy=%s host=%s path=%s range=%s" % (self.proxy, self.url.hostname, self.url.path, self.range)
+
+    def handle_connect (self):
+        print self, "connected"
+        buf = "GET http://%s:%s%s HTTP/1.0\r\n" % ( self.url.hostname, self.url.port or 80, self.url.path )
+        for key in filter(lambda k: k not in ("range"), self.headers.keys()): #send origin request headers
+            buf += "%s: %s\r\n" % (key, self.headers[key])
+        if self.range != (-1,-1):
+            buf += "Range: bytes=%s-%s\r\n" % (self.range[0], self.range[1])
+        buf += "\r\n"
+        self.push(buf)
+        self.start_time = time.time()
+
+    def time(self):
+        if self.stop_time == 0:
+            return time.time() - self.start_time
+        else:
+            return self.stop_time - self.start_time
+
+    def speed(self):
+        return (self.pos - self.range[0]) / self.time()
+
+    def collect_incoming_data(self, data):
+        if self.state==2: #body
+            length = len(data)
+            if self.range != (-1,-1) and self.pos + length >= self.range[1] + 1:
+                #if this request is the first one (whithout Range: ...) then the server
+                # dont send us our expected range, we must cut it at some point (here)
+                bytes_remaining = self.range[1] - ( self.pos )
+                data=data[:bytes_remaining+1]
+                print self,"cut: pos=%s length=%s => %s" % (self.pos, length, len(data))
+                length = len(data)
+                if length == 0:
+                    self.reader.handle_incoming_data(self)
+                    self.close()
+                    return
+            if not self.reader.handle_incoming_data(self, data, length):
+                self.close()
+                return
+            self.pos += length
+            if self.range != (-1,-1) and self.pos >= self.range[1]:
+                self.stop_time = time.time()
+                print self, "finished with %s kB/s" % (self.speed() / 1024)
+                self.reader.handle_incoming_data(self)
+                self.close()
+        elif self.state ==1: #header
+            self.http_header.write( data )
+        else: #status
+            self.http_status += data 
+
+    def found_terminator(self):
+        if self.state == 0: #got status-line
+            self.state = 1
+            self.set_terminator("\r\n\r\n")
+        elif self.state == 1: #got headers
+            self.state = 2
+            self.set_terminator(None)
+            self.reader.handle_incoming_http_header(self, self.http_header)
+
+class MagicHTTPProxyClient(object):
+    def __init__(self, channel, url, header):
+        self.channel = channel
+        self.config = self.channel.server.config
+        self.url = url
+        self.header = header
+
+        self.content_length = -1
+        self.header_sent = False
+        self.fetch_pos = 0
+        self.write_pos = 0
+        self.buffer = ""
+        self.blocks = list()
+        self.fetchers = list()
+
+        proxy = self.config.endpoints[ random.randint(0, len(self.config.endpoints)-1) ]
+        self.fetchers.append( Fetcher(self, proxy, self.url, self.header, (-1,-1)) )
+
+    def __str__(self):
+        return "<MagicHTTPProxyClient host=%s path=%s content_length=%s>" % (self.url.hostname, self.url.path, self.content_length)
+
+    def handle_incoming_data(self, fetcher, data=None, length=0):
+        if not data:
+            #fetcher is done, remove from list
+            self.fetchers = filter(lambda f: f != fetcher, self.fetchers)
+            print "Remove: %s" % fetcher
+        else:
+            assert fetcher.pos < fetcher.range[1] or fetcher.range == (-1,-1)
+            heappush(self.blocks, (fetcher.pos, data, length))
+
+        if not self.channel.connected:
+            print self, "request side closed the connection"
+            return False
+
+        if fetcher.range != (-1,-1) \
+                and fetcher.range[1] - (fetcher.pos+length) < self.config.fetcher_jumpstart \
+                and self.fetch_pos + 1 < self.content_length \
+                and len( filter(lambda f: f.proxy == fetcher.proxy, self.fetchers) ) < 2:
+            #Start a new fetcher if this fetcher is X-Bytes before finished his job
+            blocksize = max(int(self.config.time_slice * fetcher.speed()), self.config.minimal_blocksize)
+            fetch_range = self.next_range(blocksize)
+            self.fetchers.append( Fetcher(self, fetcher.proxy, self.url, self.header, fetch_range) )
+
+        #if len(self.blocks)>0:
+            #print self,"fetch_pos=%s write_pos=%s get=%s with length=%s pending=%s" % (self.fetch_pos, self.write_pos, min(self.blocks)[0],min(self.blocks)[2], len(self.blocks))
+ 
+        buf = ""
+        while len(self.blocks)>0 and min(self.blocks)[0] == self.write_pos:
+            item = heappop(self.blocks)
+            buf += item[1]
+            self.write_pos += item[2]
+
+        if buf != "":
+            self.channel.push(buf)
+
+        if self.write_pos + 1 >= self.content_length:
+            print self, "job done %s blocks left" % len(self.blocks)
+            self.channel.close_when_done()
+        return True
+
+    def next_range(self, suggested_blocksize):
+        assert self.content_length != -1
+        start = self.fetch_pos
+        self.fetch_pos = min(self.fetch_pos + suggested_blocksize, self.content_length)
+        return (start, self.fetch_pos-1)
+
+    def handle_incoming_http_header(self, fetcher, header):
+        if not self.channel.connected:
+            return
+        if self.header_sent:
+            pass
+        else:
+            self.header_sent = True
+
+            # Sends header from first response
+            header.seek(0)
+            headers = httplib.HTTPMessage(header)
+
+            content_length = filter(lambda i: i == "content-length", headers.dict.keys())
+            if len(content_length) == 1:
+                content_length = int(headers.dict["content-length"])
+                if content_length >= self.config.threshold:
+                    self.content_length = content_length
+                    fetcher.range = self.next_range(self.config.initial_blocksize)
+                    for proxy in filter(lambda p: fetcher.proxy != p, self.config.endpoints):
+                        if self.fetch_pos == self.content_length -1:
+                            break
+                        self.fetchers.append(Fetcher( self, proxy, self.url, self.header, self.next_range(self.config.initial_blocksize)))
+
+            else:
+                content_length = None
+
+            buf = "HTTP/1.1 200 OK\r\n"
+            for key in filter(lambda k: k not in ("content-range", "content-length"), headers.dict.keys()):
+                buf += "%s: %s\r\n" % (key, headers.dict[key])
+            if content_length:
+                buf += "Content-Length: %s\r\n" % content_length
+                buf += "Content-Range: bytes %s-%s/%s\r\n" % (0, content_length-1, content_length)
+            buf += "X-Proxy: Magicproxy (superpower activated)\r\n"
+            buf += "\r\n"
+            self.channel.push(buf)
+
+class HTTPChannel(asynchat.async_chat):
+    def __init__(self, server, sock, addr):
+        self.server = server
+        self.data = StringIO.StringIO()
+
+        asynchat.async_chat.__init__(self, sock)
+        self.set_terminator("\r\n\r\n")
+
+    def handle_close(self):
+        self.connected = False
+        self.close()
+
+    def collect_incoming_data(self, data):
+        self.data.write(data)
+        if self.data.tell() > 16384:
+            self.close_when_done()
+
+    def found_terminator(self):
+        # parse http header
+        self.data.seek(0)
+        self.request = string.split(self.data.readline(), None, 2)
+        if len(self.request) != 3:
+            # badly formed request; just shut down
+            self.close_when_done()
+        else:
+            self.set_terminator(None)
+            headers = httplib.HTTPMessage(self.data).dict
+            self.handle_request(self.request[0], self.request[1], headers)
+
+    def handle_request(self, method, path, headers):
+        url = urlparse.urlparse(path)
+        if method != "GET" or url.query != "":
+            #do not handle non-GET or GET with Query (?foo=bla) requests
+            proxy = self.server.config.endpoints[ int( md5.md5(url.hostname).hexdigest(),16 ) % len(self.server.config.endpoints) ]
+            print Fetcher(self, proxy, url, headers, (-1,-1))
+        else:
+            MagicHTTPProxyClient(self, url, headers)
+
+    def handle_incoming_http_header(self,fetcher,header):
+        header.seek(0)
+        headers = httplib.HTTPMessage(header)
+        buf = "HTTP/1.1 200 OK\r\n"
+        buf += "\r\n".join(map(lambda hdr: "%s: %s" % (hdr,headers.dict[hdr]), headers.dict.keys()))
+        buf += "\r\n\r\n"
+        self.push(buf)
+
+
+    def handle_incoming_data(self, fetcher, data=None, length=0):
+        if data:
+            self.push(data)
+        return True
+
+class HTTPProxyServer(asyncore.dispatcher):
+    def __init__(self,config):
+        self.config = config
+        asyncore.dispatcher.__init__(self)
+        self.create_socket(socket.AF_INET, socket.SOCK_STREAM)
+        self.set_reuse_addr()
+        self.bind(self.config.listen)
+        self.listen(5)
+
+    def __str__(self):
+        return "<HTTPProxyServer listen=%s:%s>" % self.config.listen
+
+    def handle_accept(self):
+        conn, addr = self.accept()
+        HTTPChannel(self, conn, addr)
+
+def main():
+    proxy = HTTPProxyServer(DefaultConfiguration)
+    print proxy
+    asyncore.loop()