[ashd.git] / python / ashd / serve.py

import sys, os, threading, time, logging, select, Queue
import perf

log = logging.getLogger("ashd.serve")
seq = 1
seqlk = threading.Lock()

def reqseq():
    global seq
    with seqlk:
        s = seq
        seq += 1
        return s

class closed(IOError):
    def __init__(self):
        super(closed, self).__init__("The client has closed the connection.")

class reqthread(threading.Thread):
    def __init__(self, name=None, **kw):
        if name is None:
            name = "Request handler %i" % reqseq()
        super(reqthread, self).__init__(name=name, **kw)

class wsgirequest(object):
    def __init__(self, handler):
        self.status = None
        self.headers = []
        self.respsent = False
        self.handler = handler
        self.buffer = bytearray()

    def handlewsgi(self):
        raise Exception()
    def fileno(self):
        raise Exception()
    def writehead(self, status, headers):
        raise Exception()
    def flush(self):
        raise Exception()
    def close(self):
        pass
    def writedata(self, data):
        self.buffer.extend(data)

    def flushreq(self):
        if not self.respsent:
            if not self.status:
                raise Exception("Cannot send response body before starting response.")
            self.respsent = True
            self.writehead(self.status, self.headers)

    def write(self, data):
        if not data:
            return
        self.flushreq()
        self.writedata(data)
        self.handler.ckflush(self)

    def startreq(self, status, headers, exc_info=None):
        if self.status:
            if exc_info:
                try:
                    if self.respsent:
                        raise exc_info[1]
                finally:
                    exc_info = None
            else:
                raise Exception("Can only start responding once.")
        self.status = status
        self.headers = headers
        return self.write

class handler(object):
    def handle(self, request):
        raise Exception()
    def ckflush(self, req):
        while len(req.buffer) > 0:
            rls, wls, els = select.select([], [req], [req])
            req.flush()
    def close(self):
        pass

    @classmethod
    def parseargs(cls, **args):
        if len(args) > 0:
            raise ValueError("unknown handler argument: " + iter(args).next())
        return {}

class single(handler):
    cname = "single"

    def handle(self, req):
        try:
            env = req.mkenv()
            with perf.request(env) as reqevent:
                respiter = req.handlewsgi(env, req.startreq)
                for data in respiter:
                    req.write(data)
                if req.status:
                    reqevent.response([req.status, req.headers])
                    req.flushreq()
                self.ckflush(req)
        except closed:
            pass
        except:
            log.error("exception occurred when handling request", exc_info=True)
        finally:
            req.close()

class freethread(handler):
    cname = "free"

    def __init__(self, max=None, timeout=None, **kw):
        super(freethread, self).__init__(**kw)
        self.current = set()
        self.lk = threading.Lock()
        self.tcond = threading.Condition(self.lk)
        self.max = max
        self.timeout = timeout

    @classmethod
    def parseargs(cls, max=None, abort=None, **args):
        ret = super(freethread, cls).parseargs(**args)
        if max:
            ret["max"] = int(max)
        if abort:
            ret["timeout"] = int(abort)
        return ret

    def handle(self, req):
        with self.lk:
            if self.max is not None:
                if self.timeout is not None:
                    now = start = time.time()
                    while len(self.current) >= self.max:
                        self.tcond.wait(start + self.timeout - now)
                        now = time.time()
                        if now - start > self.timeout:
                            os.abort()
                else:
                    while len(self.current) >= self.max:
                        self.tcond.wait()
            th = reqthread(target=self.run, args=[req])
            th.start()
            while th.is_alive() and th not in self.current:
                self.tcond.wait()

    def run(self, req):
        try:
            th = threading.current_thread()
            with self.lk:
                self.current.add(th)
                self.tcond.notify_all()
            try:
                env = req.mkenv()
                with perf.request(env) as reqevent:
                    respiter = req.handlewsgi(env, req.startreq)
                    for data in respiter:
                        req.write(data)
                    if req.status:
                        reqevent.response([req.status, req.headers])
                        req.flushreq()
                    self.ckflush(req)
            except closed:
                pass
            except:
                log.error("exception occurred when handling request", exc_info=True)
            finally:
                with self.lk:
                    self.current.remove(th)
                    self.tcond.notify_all()
        finally:
            req.close()

    def close(self):
        while True:
            with self.lk:
                if len(self.current) > 0:
                    th = iter(self.current).next()
                else:
                    return
            th.join()

class resplex(handler):
    cname = "rplex"

    def __init__(self, max=None, **kw):
        super(resplex, self).__init__(**kw)
        self.current = set()
        self.lk = threading.Lock()
        self.tcond = threading.Condition(self.lk)
        self.max = max
        self.cqueue = Queue.Queue(5)
        self.cnpipe = os.pipe()
        self.rthread = reqthread(name="Response thread", target=self.handle2)
        self.rthread.start()

    @classmethod
    def parseargs(cls, max=None, **args):
        ret = super(resplex, cls).parseargs(**args)
        if max:
            ret["max"] = int(max)
        return ret

    def ckflush(self, req):
        raise Exception("resplex handler does not support the write() function")

    def handle(self, req):
        with self.lk:
            if self.max is not None:
                while len(self.current) >= self.max:
                    self.tcond.wait()
            th = reqthread(target=self.handle1, args=[req])
            th.start()
            while th.is_alive() and th not in self.current:
                self.tcond.wait()

    def handle1(self, req):
        try:
            th = threading.current_thread()
            with self.lk:
                self.current.add(th)
                self.tcond.notify_all()
            try:
                env = req.mkenv()
                respobj = req.handlewsgi(env, req.startreq)
                respiter = iter(respobj)
                if not req.status:
                    log.error("request handler returned without calling start_request")
                    if hasattr(respiter, "close"):
                        respiter.close()
                    return
                else:
                    self.cqueue.put((req, respiter))
                    os.write(self.cnpipe[1], " ")
                    req = None
            finally:
                with self.lk:
                    self.current.remove(th)
                    self.tcond.notify_all()
        except closed:
            pass
        except:
            log.error("exception occurred when handling request", exc_info=True)
        finally:
            if req is not None:
                req.close()

    def handle2(self):
        try:
            rp = self.cnpipe[0]
            current = {}

            def closereq(req):
                respiter = current[req]
                try:
                    if respiter is not None and hasattr(respiter, "close"):
                        respiter.close()
                except:
                    log.error("exception occurred when closing iterator", exc_info=True)
                try:
                    req.close()
                except:
                    log.error("exception occurred when closing request", exc_info=True)
                del current[req]
            def ckiter(req):
                respiter = current[req]
                if respiter is not None:
                    rem = False
                    try:
                        data = respiter.next()
                    except StopIteration:
                        rem = True
                        try:
                            req.flushreq()
                        except:
                            log.error("exception occurred when handling response data", exc_info=True)
                    except:
                        rem = True
                        log.error("exception occurred when iterating response", exc_info=True)
                    if not rem:
                        if data:
                            try:
                                req.flushreq()
                                req.writedata(data)
                            except:
                                log.error("exception occurred when handling response data", exc_info=True)
                                rem = True
                    if rem:
                        current[req] = None
                        try:
                            if hasattr(respiter, "close"):
                                respiter.close()
                        except:
                            log.error("exception occurred when closing iterator", exc_info=True)
                        respiter = None
                if respiter is None and not req.buffer:
                    closereq(req)

            while True:
                bufl = list(req for req in current.iterkeys() if req.buffer)
                rls, wls, els = select.select([rp], bufl, [rp] + bufl)
                if rp in rls:
                    ret = os.read(rp, 1024)
                    if not ret:
                        os.close(rp)
                        return
                    try:
                        while True:
                            req, respiter = self.cqueue.get(False)
                            current[req] = respiter
                            ckiter(req)
                    except Queue.Empty:
                        pass
                for req in wls:
                    try:
                        req.flush()
                    except closed:
                        closereq(req)
                    except:
                        log.error("exception occurred when writing response", exc_info=True)
                        closereq(req)
                    else:
                        if len(req.buffer) < 65536:
                            ckiter(req)
        except:
            log.critical("unexpected exception occurred in response handler thread", exc_info=True)
            os.abort()

    def close(self):
        while True:
            with self.lk:
                if len(self.current) > 0:
                    th = iter(self.current).next()
                else:
                    break
            th.join()
        os.close(self.cnpipe[1])
        self.rthread.join()

names = dict((cls.cname, cls) for cls in globals().itervalues() if
             isinstance(cls, type) and
             issubclass(cls, handler) and
             hasattr(cls, "cname"))

def parsehspec(spec):
    if ":" not in spec:
        return spec, {}
    nm, spec = spec.split(":", 1)
    args = {}
    while spec:
        if "," in spec:
            part, spec = spec.split(",", 1)
        else:
            part, spec = spec, None
        if "=" in part:
            key, val = part.split("=", 1)
        else:
            key, val = part, ""
        args[key] = val
    return nm, args
Commit	Line	Data
8f410ce7 FT	1	import sys, os, threading, time, logging, select, Queue
8f410ce7 FT	2	import perf
63090e5a FT	3
	4	log = logging.getLogger("ashd.serve")
	5	seq = 1
	6	seqlk = threading.Lock()
	7
	8	def reqseq():
	9	global seq
8f410ce7	10	with seqlk:
63090e5a FT	11	s = seq
	12	seq += 1
	13	return s
63090e5a FT	14
	15	class closed(IOError):
	16	def __init__(self):
	17	super(closed, self).__init__("The client has closed the connection.")
	18
8f410ce7 FT	19	class reqthread(threading.Thread):
	20	def __init__(self, name=None, **kw):
	21	if name is None:
	22	name = "Request handler %i" % reqseq()
	23	super(reqthread, self).__init__(name=name, **kw)
	24
	25	class wsgirequest(object):
	26	def __init__(self, handler):
63090e5a FT	27	self.status = None
	28	self.headers = []
	29	self.respsent = False
8f410ce7 FT	30	self.handler = handler
8f410ce7 FT	31	self.buffer = bytearray()
63090e5a FT	32
	33	def handlewsgi(self):
	34	raise Exception()
8f410ce7 FT	35	def fileno(self):
8f410ce7 FT	36	raise Exception()
63090e5a FT	37	def writehead(self, status, headers):
63090e5a FT	38	raise Exception()
8f410ce7	39	def flush(self):
63090e5a	40	raise Exception()
8f410ce7 FT	41	def close(self):
	42	pass
	43	def writedata(self, data):
	44	self.buffer.extend(data)
63090e5a FT	45
	46	def flushreq(self):
	47	if not self.respsent:
	48	if not self.status:
	49	raise Exception("Cannot send response body before starting response.")
	50	self.respsent = True
	51	self.writehead(self.status, self.headers)
	52
8f410ce7 FT	53	def write(self, data):
	54	if not data:
	55	return
	56	self.flushreq()
	57	self.writedata(data)
	58	self.handler.ckflush(self)
	59
63090e5a FT	60	def startreq(self, status, headers, exc_info=None):
63090e5a FT	61	if self.status:
8f410ce7	62	if exc_info:
63090e5a FT	63	try:
63090e5a FT	64	if self.respsent:
8f410ce7	65	raise exc_info[1]
63090e5a	66	finally:
8f410ce7	67	exc_info = None
63090e5a FT	68	else:
	69	raise Exception("Can only start responding once.")
	70	self.status = status
	71	self.headers = headers
	72	return self.write
8f410ce7 FT	73
	74	class handler(object):
	75	def handle(self, request):
	76	raise Exception()
	77	def ckflush(self, req):
	78	while len(req.buffer) > 0:
	79	rls, wls, els = select.select([], [req], [req])
	80	req.flush()
	81	def close(self):
	82	pass
	83
	84	@classmethod
	85	def parseargs(cls, **args):
	86	if len(args) > 0:
	87	raise ValueError("unknown handler argument: " + iter(args).next())
	88	return {}
	89
	90	class single(handler):
	91	cname = "single"
	92
	93	def handle(self, req):
63090e5a	94	try:
8f410ce7 FT	95	env = req.mkenv()
	96	with perf.request(env) as reqevent:
	97	respiter = req.handlewsgi(env, req.startreq)
63090e5a	98	for data in respiter:
8f410ce7 FT	99	req.write(data)
	100	if req.status:
	101	reqevent.response([req.status, req.headers])
	102	req.flushreq()
	103	self.ckflush(req)
63090e5a FT	104	except closed:
63090e5a FT	105	pass
8f410ce7 FT	106	except:
	107	log.error("exception occurred when handling request", exc_info=True)
	108	finally:
	109	req.close()
	110
	111	class freethread(handler):
	112	cname = "free"
63090e5a	113
8f410ce7 FT	114	def __init__(self, max=None, timeout=None, **kw):
	115	super(freethread, self).__init__(**kw)
	116	self.current = set()
	117	self.lk = threading.Lock()
	118	self.tcond = threading.Condition(self.lk)
	119	self.max = max
	120	self.timeout = timeout
63090e5a	121
8f410ce7 FT	122	@classmethod
	123	def parseargs(cls, max=None, abort=None, **args):
	124	ret = super(freethread, cls).parseargs(**args)
	125	if max:
	126	ret["max"] = int(max)
	127	if abort:
	128	ret["timeout"] = int(abort)
	129	return ret
63090e5a	130
8f410ce7 FT	131	def handle(self, req):
	132	with self.lk:
	133	if self.max is not None:
	134	if self.timeout is not None:
	135	now = start = time.time()
	136	while len(self.current) >= self.max:
	137	self.tcond.wait(start + self.timeout - now)
	138	now = time.time()
	139	if now - start > self.timeout:
	140	os.abort()
	141	else:
	142	while len(self.current) >= self.max:
	143	self.tcond.wait()
	144	th = reqthread(target=self.run, args=[req])
	145	th.start()
	146	while th.is_alive() and th not in self.current:
	147	self.tcond.wait()
	148
	149	def run(self, req):
63090e5a	150	try:
8f410ce7 FT	151	th = threading.current_thread()
	152	with self.lk:
	153	self.current.add(th)
	154	self.tcond.notify_all()
	155	try:
	156	env = req.mkenv()
	157	with perf.request(env) as reqevent:
	158	respiter = req.handlewsgi(env, req.startreq)
	159	for data in respiter:
	160	req.write(data)
	161	if req.status:
	162	reqevent.response([req.status, req.headers])
	163	req.flushreq()
	164	self.ckflush(req)
	165	except closed:
	166	pass
	167	except:
	168	log.error("exception occurred when handling request", exc_info=True)
	169	finally:
	170	with self.lk:
	171	self.current.remove(th)
	172	self.tcond.notify_all()
63090e5a	173	finally:
8f410ce7 FT	174	req.close()
	175
	176	def close(self):
	177	while True:
	178	with self.lk:
	179	if len(self.current) > 0:
	180	th = iter(self.current).next()
	181	else:
	182	return
	183	th.join()
	184
	185	class resplex(handler):
	186	cname = "rplex"
	187
	188	def __init__(self, max=None, **kw):
	189	super(resplex, self).__init__(**kw)
	190	self.current = set()
	191	self.lk = threading.Lock()
	192	self.tcond = threading.Condition(self.lk)
	193	self.max = max
	194	self.cqueue = Queue.Queue(5)
	195	self.cnpipe = os.pipe()
	196	self.rthread = reqthread(name="Response thread", target=self.handle2)
	197	self.rthread.start()
	198
	199	@classmethod
	200	def parseargs(cls, max=None, **args):
	201	ret = super(resplex, cls).parseargs(**args)
	202	if max:
	203	ret["max"] = int(max)
	204	return ret
	205
	206	def ckflush(self, req):
	207	raise Exception("resplex handler does not support the write() function")
63090e5a	208
8f410ce7 FT	209	def handle(self, req):
	210	with self.lk:
	211	if self.max is not None:
	212	while len(self.current) >= self.max:
	213	self.tcond.wait()
	214	th = reqthread(target=self.handle1, args=[req])
	215	th.start()
	216	while th.is_alive() and th not in self.current:
	217	self.tcond.wait()
	218
	219	def handle1(self, req):
63090e5a	220	try:
8f410ce7 FT	221	th = threading.current_thread()
	222	with self.lk:
	223	self.current.add(th)
	224	self.tcond.notify_all()
	225	try:
	226	env = req.mkenv()
	227	respobj = req.handlewsgi(env, req.startreq)
	228	respiter = iter(respobj)
	229	if not req.status:
	230	log.error("request handler returned without calling start_request")
	231	if hasattr(respiter, "close"):
	232	respiter.close()
	233	return
	234	else:
	235	self.cqueue.put((req, respiter))
	236	os.write(self.cnpipe[1], " ")
	237	req = None
	238	finally:
	239	with self.lk:
	240	self.current.remove(th)
	241	self.tcond.notify_all()
	242	except closed:
	243	pass
	244	except:
	245	log.error("exception occurred when handling request", exc_info=True)
63090e5a	246	finally:
8f410ce7 FT	247	if req is not None:
8f410ce7 FT	248	req.close()
63090e5a	249
8f410ce7	250	def handle2(self):
63090e5a	251	try:
8f410ce7 FT	252	rp = self.cnpipe[0]
8f410ce7 FT	253	current = {}
e0c88e73	254
8f410ce7 FT	255	def closereq(req):
	256	respiter = current[req]
	257	try:
	258	if respiter is not None and hasattr(respiter, "close"):
	259	respiter.close()
	260	except:
	261	log.error("exception occurred when closing iterator", exc_info=True)
	262	try:
	263	req.close()
	264	except:
	265	log.error("exception occurred when closing request", exc_info=True)
	266	del current[req]
	267	def ckiter(req):
	268	respiter = current[req]
	269	if respiter is not None:
	270	rem = False
	271	try:
	272	data = respiter.next()
	273	except StopIteration:
	274	rem = True
	275	try:
	276	req.flushreq()
	277	except:
	278	log.error("exception occurred when handling response data", exc_info=True)
	279	except:
	280	rem = True
	281	log.error("exception occurred when iterating response", exc_info=True)
	282	if not rem:
	283	if data:
	284	try:
	285	req.flushreq()
	286	req.writedata(data)
	287	except:
	288	log.error("exception occurred when handling response data", exc_info=True)
	289	rem = True
	290	if rem:
	291	current[req] = None
	292	try:
	293	if hasattr(respiter, "close"):
	294	respiter.close()
	295	except:
	296	log.error("exception occurred when closing iterator", exc_info=True)
	297	respiter = None
	298	if respiter is None and not req.buffer:
	299	closereq(req)
	300
	301	while True:
	302	bufl = list(req for req in current.iterkeys() if req.buffer)
	303	rls, wls, els = select.select([rp], bufl, [rp] + bufl)
	304	if rp in rls:
	305	ret = os.read(rp, 1024)
	306	if not ret:
	307	os.close(rp)
	308	return
	309	try:
	310	while True:
	311	req, respiter = self.cqueue.get(False)
	312	current[req] = respiter
	313	ckiter(req)
	314	except Queue.Empty:
	315	pass
	316	for req in wls:
	317	try:
	318	req.flush()
319	except closed:
320	closereq(req)
321	except:
322	log.error("exception occurred when writing response", exc_info=True)
323	closereq(req)
324	else:
325	if len(req.buffer) < 65536:
326	ckiter(req)
327	except:
328	log.critical("unexpected exception occurred in response handler thread", exc_info=True)
e0c88e73	329	os.abort()
8f410ce7 FT	330
	331	def close(self):
	332	while True:
	333	with self.lk:
	334	if len(self.current) > 0:
	335	th = iter(self.current).next()
	336	else:
	337	break
	338	th.join()
	339	os.close(self.cnpipe[1])
	340	self.rthread.join()
	341
	342	names = dict((cls.cname, cls) for cls in globals().itervalues() if
	343	isinstance(cls, type) and
	344	issubclass(cls, handler) and
	345	hasattr(cls, "cname"))
	346
	347	def parsehspec(spec):
	348	if ":" not in spec:
	349	return spec, {}
	350	nm, spec = spec.split(":", 1)
	351	args = {}
	352	while spec:
	353	if "," in spec:
	354	part, spec = spec.split(",", 1)
	355	else:
	356	part, spec = spec, None
	357	if "=" in part:
	358	key, val = part.split("=", 1)
	359	else:
	360	key, val = part, ""
	361	args[key] = val
	362	return nm, args