Initial commit

nicoscache.py

@@ -0,0 +1,171 @@
+import re
+from ast import literal_eval
+from streams import Stream
+from secop import EnumConvert
+
+
+OP_TELL = '='
+OP_ASK = '?'
+OP_WILDCARD = '*'
+OP_SUBSCRIBE = ':'
+OP_UNSUBSCRIBE = '|'
+OP_TELLOLD = '!'
+OP_LOCK = '$'
+OP_REWRITE = '~'
+
+OP_LOCK_LOCK = '+'
+OP_LOCK_UNLOCK = '-'
+
+# put flags between key and op...
+FLAG_NO_STORE = '#'
+
+# end/sync special token
+END_MARKER = '###'
+SYNC_MARKER = '#sync#'
+PING = '#ping#'
+
+# Time constant
+CYCLETIME = 0.1
+
+
+opkeys = OP_TELL + OP_ASK + OP_WILDCARD + OP_SUBSCRIBE + OP_UNSUBSCRIBE + \
+    OP_TELLOLD + OP_LOCK + OP_REWRITE
+
+# regular expression matching a cache protocol message
+msg_pattern = re.compile(r'''
+    ^ (?:
+      \s* (?P<time>\d+\.?\d*)?                   # timestamp
+      \s* (?P<ttlop>[+-]?)                       # ttl operator
+      \s* (?P<ttl>\d+\.?\d*(?:[eE][+-]?\d+)?)?   # ttl
+      \s* (?P<tsop>@)                            # timestamp mark
+    )?
+    \s* (?P<key>[^%(opkeys)s]*?)                 # key
+    \s* (?P<op>[%(opkeys)s])                     # operator
+    \s* (?P<value>[^\r\n]*?)                     # value
+    \s* \r?$                                     # skip cr before line end
+    ''' % dict(opkeys=opkeys), re.X)
+
+
+class NicosStream(Stream):
+    def __init__(self, uri, name=None):
+        self.devices = {}
+        self.units = {}  # global unit dict when overridden in streams
+        self.aliases = {}
+        self.descr = {}
+        self.convert = {}
+        self.secnode_uri = {}
+        super().__init__(uri, name)
+
+    def init(self):
+        self.tags['device'] = 'nicos'
+        self.send(f'@nicos/*\n{END_MARKER}{OP_ASK}')
+        self._init = True
+
+    def do_status(self, devname, value, op):
+        self.devices[devname] = op == '='
+        return value[0]
+
+    def do_value(self, devname, value, op):
+        if op == '=':
+            if isinstance(value, (int, float)):
+                key = f'{devname}.value'
+                if key not in self.convert:
+                    self.convert[key] = float
+        self.devices[devname] = op == '='
+        return value
+
+    def do_unit(self, devname, value, op):
+        # for non-secop devices
+        self.units[f'{devname}.value'] = value
+        self.units[f'{devname}.target'] = value
+        return value
+
+    def do_alias(self, devname, value, op):
+        self.convert.pop(f'{devname}.value', None)
+        self.aliases[devname] = value
+        return value
+
+    def do_uri(self, devname, value, op):
+        self.secnode_uri[devname] = value
+        return value
+
+    def do_setup_info(self, devname, value, op):
+        for dev, (cls, descr) in value.items():
+            self.descr[dev] = descr
+            mod = descr.get('secop_module')
+            if mod:
+                params_cfg = descr.get('params_cfg', {})
+                # add datainfo for special parameters:
+                for param in 'value', 'target':
+                    dt = descr.get(f'{param}_datainfo')
+                    if dt:
+                        params_cfg[param] = {'datainfo': dt}
+                for param, cfg in params_cfg.items():
+                    dt = cfg.get('datainfo')
+                    key = f'{mod}.{param}'
+                    if dt:
+                        if dt['type'] == 'enum':
+                            self.convert[key] = EnumConvert(dt['members'])
+                        elif dt['type'] in ('double', 'scaled'):
+                            self.convert[key] = float
+                    unit = cfg.get('unit')
+                    if unit is not None:
+                        self.units[key] = unit
+        return value
+
+    def ping(self):
+        self.send(f'{PING}{OP_ASK}')
+
+    def events(self, matchmsg=msg_pattern.match):
+        if self.is_offline():
+            return
+        events = {}
+        try:
+            for line in self.get_lines():
+                match = matchmsg(line)
+                if match:
+                    data = match.groupdict()
+                    key = data['key']
+                    op = data['op']
+                    if key[:1] == '#':
+                        if key == END_MARKER:
+                            if self._init:
+                                self.notimeout()
+                                self.send(f'@nicos/{OP_SUBSCRIBE}')
+                                self._init = False
+                                break
+                        continue
+                    value = data['value']
+                    keysplit = key.split('/')
+                    param = keysplit[-1]
+                    try:
+                        value = literal_eval(value)
+                    except Exception:
+                        value = None
+                    devname = keysplit[1]
+                    devname = self.aliases.get(devname, devname)
+                    func = getattr(self, f'do_{param}', None)
+                    if func:
+                        value = func(devname, value, op)
+                    events[devname, param] = op, value, float(data['time'])
+            if self._init:
+                raise TimeoutError('timeout receiving initial values')
+        except Exception as e:
+            print(self.uri, repr(e))
+            return
+        cnt = 0
+        for ts, devname, param, op, value in sorted([t, d, p, o, v] for (d, p), (o, v, t) in events.items()):
+            descr = self.descr.get(devname)
+            mod = descr.get('secop_module', devname) if descr else devname
+            key = (mod, param)
+            if self.devices.get(devname):
+                try:
+                    value = self.convert[key](value)
+                    error = None
+                except KeyError:  # no conversion function
+                    continue
+                except TypeError:
+                    value = None
+                    error = 'error'
+                cnt += 1
+                yield key, value, error, ts