| 1 | """Management for daemon processes |
| 2 | |
| 3 | This module provides some client support for the daemon management |
| 4 | provided in the pdm.srv module. |
| 5 | """ |
| 6 | |
| 7 | import socket, pickle, struct, select, threading |
| 8 | |
| 9 | __all__ = ["client", "replclient"] |
| 10 | |
| 11 | class protoerr(Exception): |
| 12 | pass |
| 13 | |
| 14 | def resolve(spec): |
| 15 | if isinstance(spec, socket.socket): |
| 16 | return spec |
| 17 | sk = None |
| 18 | try: |
| 19 | if "/" in spec: |
| 20 | sk = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM) |
| 21 | sk.connect(spec) |
| 22 | elif spec.isdigit(): |
| 23 | sk = socket.socket(socket.AF_INET, socket.SOCK_STREAM) |
| 24 | sk.connect(("localhost", int(spec))) |
| 25 | elif ":" in spec: |
| 26 | sk = socket.socket(socket.AF_INET, socket.SOCK_STREAM) |
| 27 | p = spec.rindex(":") |
| 28 | sk.connect((spec[:p], int(spec[p + 1:]))) |
| 29 | else: |
| 30 | raise Exception("Unknown target specification %r" % spec) |
| 31 | rv = sk |
| 32 | sk = None |
| 33 | finally: |
| 34 | if sk is not None: sk.close() |
| 35 | return rv |
| 36 | |
| 37 | class client(object): |
| 38 | def __init__(self, sk, proto = None): |
| 39 | self.sk = resolve(sk) |
| 40 | self.buf = "" |
| 41 | line = self.readline() |
| 42 | if line != "+PDM1": |
| 43 | raise protoerr("Illegal protocol signature") |
| 44 | if proto is not None: |
| 45 | self.select(proto) |
| 46 | |
| 47 | def close(self): |
| 48 | self.sk.close() |
| 49 | |
| 50 | def readline(self): |
| 51 | while True: |
| 52 | p = self.buf.find("\n") |
| 53 | if p >= 0: |
| 54 | ret = self.buf[:p] |
| 55 | self.buf = self.buf[p + 1:] |
| 56 | return ret |
| 57 | ret = self.sk.recv(1024) |
| 58 | if ret == "": |
| 59 | return None |
| 60 | self.buf += ret |
| 61 | |
| 62 | def select(self, proto): |
| 63 | if "\n" in proto: |
| 64 | raise Exception("Illegal protocol specified: %r" % proto) |
| 65 | self.sk.send(proto + "\n") |
| 66 | rep = self.readline() |
| 67 | if len(rep) < 1 or rep[0] != "+": |
| 68 | raise protoerr("Error reply when selecting protocol %s: %s" % (proto, rep[1:])) |
| 69 | |
| 70 | def __enter__(self): |
| 71 | return self |
| 72 | |
| 73 | def __exit__(self, *excinfo): |
| 74 | self.close() |
| 75 | return False |
| 76 | |
| 77 | class replclient(client): |
| 78 | def __init__(self, sk): |
| 79 | super(replclient, self).__init__(sk, "repl") |
| 80 | |
| 81 | def run(self, code): |
| 82 | while True: |
| 83 | ncode = code.replace("\n\n", "\n") |
| 84 | if ncode == code: break |
| 85 | code = ncode |
| 86 | while len(code) > 0 and code[-1] == "\n": |
| 87 | code = code[:-1] |
| 88 | self.sk.send(code + "\n\n") |
| 89 | buf = "" |
| 90 | while True: |
| 91 | ln = self.readline() |
| 92 | if ln[0] == " ": |
| 93 | buf += ln[1:] + "\n" |
| 94 | elif ln[0] == "+": |
| 95 | return buf |
| 96 | elif ln[0] == "-": |
| 97 | raise protoerr("Error reply: %s" % ln[1:]) |
| 98 | else: |
| 99 | raise protoerr("Illegal reply: %s" % ln) |
| 100 | |
| 101 | class perfproxy(object): |
| 102 | def __init__(self, cl, id, proto): |
| 103 | self.cl = cl |
| 104 | self.id = id |
| 105 | self.proto = proto |
| 106 | self.subscribers = set() |
| 107 | |
| 108 | def lookup(self, name): |
| 109 | self.cl.lock.acquire() |
| 110 | try: |
| 111 | id = self.cl.nextid |
| 112 | self.cl.nextid += 1 |
| 113 | finally: |
| 114 | self.cl.lock.release() |
| 115 | (proto,) = self.cl.run("lookup", id, self.id, name) |
| 116 | proxy = perfproxy(self.cl, id, proto) |
| 117 | self.cl.proxies[id] = proxy |
| 118 | return proxy |
| 119 | |
| 120 | def listdir(self): |
| 121 | return self.cl.run("ls", self.id)[0] |
| 122 | |
| 123 | def readattr(self): |
| 124 | return self.cl.run("readattr", self.id)[0] |
| 125 | |
| 126 | def attrinfo(self): |
| 127 | return self.cl.run("attrinfo", self.id)[0] |
| 128 | |
| 129 | def invoke(self, method, *args, **kwargs): |
| 130 | return self.cl.run("invoke", self.id, method, args, kwargs)[0] |
| 131 | |
| 132 | def subscribe(self, cb): |
| 133 | if cb in self.subscribers: |
| 134 | raise ValueError("Already subscribed") |
| 135 | if len(self.subscribers) == 0: |
| 136 | self.cl.run("subs", self.id) |
| 137 | self.subscribers.add(cb) |
| 138 | |
| 139 | def unsubscribe(self, cb): |
| 140 | if cb not in self.subscribers: |
| 141 | raise ValueError("Not subscribed") |
| 142 | self.subscribers.remove(cb) |
| 143 | if len(self.subscribers) == 0: |
| 144 | self.cl.run("unsubs", self.id) |
| 145 | |
| 146 | def notify(self, ev): |
| 147 | for cb in self.subscribers: |
| 148 | try: |
| 149 | cb(ev) |
| 150 | except: pass |
| 151 | |
| 152 | def close(self): |
| 153 | self.cl.run("unbind", self.id) |
| 154 | del self.cl.proxies[self.id] |
| 155 | |
| 156 | def __enter__(self): |
| 157 | return self |
| 158 | |
| 159 | def __exit__(self, *excinfo): |
| 160 | self.close() |
| 161 | return False |
| 162 | |
| 163 | class perfclient(client): |
| 164 | def __init__(self, sk): |
| 165 | super(perfclient, self).__init__(sk, "perf") |
| 166 | self.nextid = 0 |
| 167 | self.lock = threading.Lock() |
| 168 | self.proxies = {} |
| 169 | self.names = {} |
| 170 | |
| 171 | def send(self, ob): |
| 172 | buf = pickle.dumps(ob) |
| 173 | buf = struct.pack(">l", len(buf)) + buf |
| 174 | self.sk.send(buf) |
| 175 | |
| 176 | def recvb(self, num): |
| 177 | buf = "" |
| 178 | while len(buf) < num: |
| 179 | data = self.sk.recv(num - len(buf)) |
| 180 | if data == "": |
| 181 | raise EOFError() |
| 182 | buf += data |
| 183 | return buf |
| 184 | |
| 185 | def recv(self): |
| 186 | return pickle.loads(self.recvb(struct.unpack(">l", self.recvb(4))[0])) |
| 187 | |
| 188 | def event(self, id, ev): |
| 189 | proxy = self.proxies.get(id) |
| 190 | if proxy is None: return |
| 191 | proxy.notify(ev) |
| 192 | |
| 193 | def dispatch(self, timeout = None): |
| 194 | rfd, wfd, efd = select.select([self.sk], [], [], timeout) |
| 195 | if self.sk in rfd: |
| 196 | msg = self.recv() |
| 197 | if msg[0] == "*": |
| 198 | self.event(msg[1], msg[2]) |
| 199 | else: |
| 200 | raise ValueError("Unexpected non-event message: %r" % msg[0]) |
| 201 | |
| 202 | def recvreply(self): |
| 203 | while True: |
| 204 | reply = self.recv() |
| 205 | if reply[0] in ("+", "-"): |
| 206 | return reply |
| 207 | elif reply[0] == "*": |
| 208 | self.event(reply[1], reply[2]) |
| 209 | else: |
| 210 | raise ValueError("Illegal reply header: %r" % reply[0]) |
| 211 | |
| 212 | def run(self, cmd, *args): |
| 213 | self.lock.acquire() |
| 214 | try: |
| 215 | self.send((cmd,) + args) |
| 216 | reply = self.recvreply() |
| 217 | if reply[0] == "+": |
| 218 | return reply[1:] |
| 219 | else: |
| 220 | raise reply[1] |
| 221 | finally: |
| 222 | self.lock.release() |
| 223 | |
| 224 | def lookup(self, module, obnm): |
| 225 | self.lock.acquire() |
| 226 | try: |
| 227 | id = self.nextid |
| 228 | self.nextid += 1 |
| 229 | finally: |
| 230 | self.lock.release() |
| 231 | (proto,) = self.run("bind", id, module, obnm) |
| 232 | proxy = perfproxy(self, id, proto) |
| 233 | self.proxies[id] = proxy |
| 234 | return proxy |
| 235 | |
| 236 | def find(self, name): |
| 237 | ret = self.names.get(name) |
| 238 | if ret is None: |
| 239 | if "/" in name: |
| 240 | p = name.rindex("/") |
| 241 | ret = self.find(name[:p]).lookup(name[p + 1:]) |
| 242 | else: |
| 243 | p = name.rindex(".") |
| 244 | ret = self.lookup(name[:p], name[p + 1:]) |
| 245 | self.names[name] = ret |
| 246 | return ret |