add counter app in python

cmd/tmsp/cli.go

@@ -45,6 +45,13 @@ func main() {
 				cmdConsole(app, c)
 			},
 		},
+		{
+			Name:  "echo",
+			Usage: "Have the application echo a message",
+			Action: func(c *cli.Context) {
+				cmdEcho(c)
+			},
+		},
 		{
 			Name:  "info",
 			Usage: "Get some info about the application",
@@ -140,6 +147,19 @@ func cmdConsole(app *cli.App, c *cli.Context) {
 	}
 }
 
+// Have the application echo a message
+func cmdEcho(c *cli.Context) {
+	args := c.Args()
+	if len(args) != 1 {
+		Exit("echo takes 1 argument")
+	}
+	res, err := makeRequest(conn, types.RequestEcho{args[0]})
+	if err != nil {
+		Exit(err.Error())
+	}
+	fmt.Println(res)
+}
+
 // Get some info from the application
 func cmdInfo(c *cli.Context) {
 	res, err := makeRequest(conn, types.RequestInfo{})

example/python/app.py

@@ -0,0 +1,83 @@
+
+import sys
+sys.path.insert(0, './tmsp')
+
+from wire import *
+from server import *
+
+
+# tmsp application interface
+
+class CounterApplication():
+    def __init__(self):
+        self.hashCount = 0
+	self.txCount = 0
+	self.commitCount = 0
+
+    def open(self):
+	    return CounterAppContext(self)
+
+class CounterAppContext():
+	def __init__(self, app):
+	    self.app = app
+	    self.hashCount = app.hashCount
+	    self.txCount = app.txCount
+	    self.commitCount = app.commitCount
+	    self.serial = False
+	    
+	def echo(self, msg):
+		return msg, 0
+
+	def info(self):
+		return ["hash, tx, commit counts:%d, %d, %d"%(self.hashCount, self.txCount, self.commitCount)], 0
+
+	def set_option(self, key, value):
+		if key == "serial" and value == "on":
+			self.serial = True
+		return 0
+
+	def append_tx(self, txBytes):
+		if self.serial:
+			txValue = decode_big_endian(BytesReader(txBytes), len(txBytes))
+			if txValue != self.txCount:
+				return [], 1
+		self.txCount += 1
+		return None, 0
+
+	def get_hash(self):
+		self.hashCount += 1
+		if self.txCount == 0:
+			return "", 0
+		return str(encode_big_endian(self.txCount, 8)), 0
+
+	def commit(self):
+		return 0 
+
+	def rollback(self):
+		return 0
+
+	def add_listener(self):
+		return 0
+
+	def rm_listener(self):
+		return 0
+
+	def event(self):
+		return 
+
+ 
+if __name__ == '__main__':
+    l = len(sys.argv)
+    if l == 1:
+       port = 46658
+    elif l == 2: 
+        port = int(sys.argv[1])
+    else:
+        print "too many arguments"
+        quit()
+
+    print 'TMSP Demo APP (Python)'
+
+    app = CounterApplication()	
+    server = TMSPServer(app, port)
+    server.main_loop()

example/python/tmsp/msg.py

@@ -0,0 +1,54 @@
+from wire import *
+
+# map type_byte to message name
+message_types = {
+0x01 : "echo",
+0x02 : "flush",
+0x03 : "info",
+0x04 : "set_option",
+0x21 : "append_tx",
+0x22 : "get_hash",
+0x23 : "commit",
+0x24 : "rollback",
+0x25 : "add_listener",
+0x26 : "rm_listener",
+}
+
+# return the decoded arguments of tmsp messages
+class RequestDecoder():
+	def __init__(self, reader):
+		self.reader = reader
+
+	def echo(self):
+		return decode_string(self.reader)
+
+	def flush(self):
+		return 
+
+	def info(self):
+		return
+
+	def set_option(self):
+		return decode_string(self.reader), decode_string(self.reader)
+
+	def append_tx(self):
+		return decode_string(self.reader)
+
+	def get_hash(self):
+		return 
+
+	def commit(self):
+		return 
+
+	def rollback(self):
+		return 
+
+	def add_listener(self):
+		# TODO
+		return 
+
+	def rm_listener(self):
+		# TODO
+		return 
+
+

example/python/tmsp/reader.py

@@ -0,0 +1,31 @@
+
+# Simple read() method around a bytearray
+class BytesReader():
+	def __init__(self, b):
+		self.buf = b
+
+	def read(self, n):
+		if len(self.buf) < n:
+			# TODO: exception
+			return
+		r = self.buf[:n]
+		self.buf = self.buf[n:]
+		return r
+
+# Buffer bytes off a tcp connection and read them off in chunks
+class ConnReader():
+	def __init__(self, conn):
+		self.conn = conn
+		self.buf = bytearray()
+
+	# blocking 
+	def read(self, n):
+		while n > len(self.buf):
+			moreBuf = self.conn.recv(1024)
+			if not moreBuf:
+				raise IOError("dead connection")
+			self.buf = self.buf + bytearray(moreBuf)
+
+		r = self.buf[:n]
+		self.buf = self.buf[n:]
+		return r

example/python/tmsp/server.py

@@ -0,0 +1,134 @@
+import socket
+import select
+import sys
+import os
+
+
+from wire import *
+from reader import *
+from msg import *
+
+# TMSP server responds to messges by calling methods on the app
+class TMSPServer():
+    def __init__(self, app, port=5410):
+	self.app = app
+	self.appMap = {} # map conn file descriptors to (appContext, msgDecoder)
+
+        self.port = port 
+        self.listen_backlog = 10
+
+        self.listener = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+        self.listener.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
+        self.listener.setblocking(0)
+        self.listener.bind(('', port))
+
+        self.listener.listen(self.listen_backlog)
+
+        self.shutdown = False
+
+        self.read_list = [self.listener]
+        self.write_list = []
+
+    def handle_new_connection(self, r):
+        new_fd, new_addr = r.accept()
+        self.read_list.append(new_fd)
+        self.write_list.append(new_fd)
+        print 'new connection to', new_addr
+
+	appContext = self.app.open()
+	self.appMap[new_fd] = (appContext, RequestDecoder(ConnReader(new_fd)))
+
+    def handle_conn_closed(self, r):
+        self.read_list.remove(r)
+        self.write_list.remove(r)
+        r.close()
+        print "connection closed"
+
+    def handle_recv(self, r):
+	appCtx, conn = self.appMap[r]
+	response = bytearray()
+	while True:
+		try:
+		    # first read the request type and get the msg decoder
+		    typeByte = conn.reader.read(1)
+		    typeByte = int(typeByte[0])
+		    resTypeByte = typeByte+0x10
+		    req_type = message_types[typeByte]
+
+		    if req_type == "flush":
+			    response += bytearray([resTypeByte]) 
+			    sent = r.send(str(response))
+			    return
+
+		    decoder = getattr(conn, req_type)
+
+		    req_args = decoder()
+		    req_f = getattr(appCtx, req_type)
+		    if req_args == None:
+			res = req_f()
+		    elif isinstance(req_args, tuple):
+			res = req_f(*req_args)
+		    else:
+			res = req_f(req_args)
+
+		    if isinstance(res, tuple):
+	 	    	res, ret_code = res
+		    else:
+		    	ret_code = res
+			res = None
+
+		    if ret_code != 0:
+			    print "non-zero retcode:", ret_code
+			    return
+
+		    if req_type in ("echo", "info"): # these dont return a ret code
+		    	response += bytearray([resTypeByte]) + encode(res)
+		    else:
+		    	response += bytearray([resTypeByte]) + encode(ret_code) + encode(res)
+		except TypeError as e: 
+			print "TypeError on reading from connection:", e
+			self.handle_conn_closed(r)
+			return
+		except ValueError as e: 
+			print "ValueError on reading from connection:", e
+			self.handle_conn_closed(r)
+			return
+		except IOError as e: 
+			print "IOError on reading from connection:", e
+			self.handle_conn_closed(r)
+			return
+		except:
+			print "error reading from connection", sys.exc_info()[0] # TODO better
+			self.handle_conn_closed(r)
+			return
+
+    def main_loop(self):
+        while not self.shutdown:
+            r_list, w_list, _ = select.select(self.read_list, self.write_list, [], 2.5)
+
+            for r in r_list:
+                if (r == self.listener):  
+                    try:
+                        self.handle_new_connection(r)
+
+			# undo adding to read list ...
+                    except NameError as e: 
+			print "Could not connect due to NameError:", e
+                    except TypeError as e: 
+			print "Could not connect due to TypeError:", e
+		    except:
+			print "Could not connect due to unexpected error:", sys.exc_info()[0]
+                else: 
+                    self.handle_recv(r)
+
+
+
+    def handle_shutdown(self):
+        for r in self.read_list:
+            r.close()
+        for w in self.write_list:
+            try:
+                w.close()
+            except: pass
+        self.shutdown = True
+

example/python/tmsp/wire.py

@@ -0,0 +1,99 @@
+
+# the decoder works off a reader
+# the encoder returns bytearray
+
+def bytes2hex(b):
+	if type(b) in (str, unicode):
+		return "".join([hex(ord(c))[2:].zfill(2) for c in b])
+	else:
+		return bytes2hex(b.decode())
+
+
+# expects uvarint64 (no crazy big nums!)
+def uvarint_size(i):
+	if i == 0:
+		return 0
+	for j in xrange(1, 8):
+		if i < 1<<j*8:
+			return j
+	return 8
+
+# expects i < 2**size
+def encode_big_endian(i, size):
+	if size == 0:
+		return bytearray()
+	return  encode_big_endian(i/256, size-1) + bytearray([i%256])
+
+def decode_big_endian(reader, size):
+	if size == 0:
+		return 0
+	firstByte = reader.read(1)[0]
+	return firstByte*(256**(size-1)) + decode_big_endian(reader, size-1)
+
+# ints are max 16 bytes long
+def encode_varint(i):
+	negate = False
+	if i < 0: 
+		negate = True
+		i = -i
+	size = uvarint_size(i)
+	if size == 0:
+		return bytearray([0])
+	big_end = encode_big_endian(i, size)
+	if negate: 
+		size += 0xF0
+	return bytearray([size]) + big_end
+
+# returns the int and whats left of the byte array
+def decode_varint(reader):
+	size = reader.read(1)[0]
+	if size == 0:
+		return 0
+
+	negate = True if size > int(0xF0) else False
+	if negate: size = size -0xF0
+	i = decode_big_endian(reader, size)
+	if negate: i = i*(-1)
+	return i 
+	
+def encode_string(s):
+	size = encode_varint(len(s))
+	return size + bytearray(s)
+
+def decode_string(reader):
+	length = decode_varint(reader)
+	return str(reader.read(length))
+
+def encode_list(s):
+	b = bytearray()
+	map(b.extend, map(encode, s))
+	return encode_varint(len(s)) + b
+
+def encode(s):
+	if s == None:
+		return bytearray()
+	if isinstance(s, int):
+		return encode_varint(s)
+	elif isinstance(s, str):
+		return encode_string(s)
+	elif isinstance(s, list):
+		return encode_list(s)
+	else:
+		print "UNSUPPORTED TYPE!", type(s), s
+
+
+import binascii
+	
+if __name__ == '__main__':
+	ns = [100,100,1000,256]
+	ss = [2,5,5,2]
+	bs = map(encode_big_endian, ns,ss)
+	ds = map(decode_big_endian, bs,ss)
+	print ns
+	print [i[0] for i in ds]
+
+	ss = ["abc", "hi there jim", "ok now what"]
+	e = map(encode_string, ss)
+	d = map(decode_string, e)
+	print ss
+	print [i[0] for i in d]