Initial commit

secop.py

@@ -0,0 +1,140 @@
+import re
+import os
+import json
+import time
+import socket
+from select import select
+from streams import Stream, Base
+
+IDN = re.compile('.*ISSE.*,SEC[oO]P,')
+DESCRIBING = re.compile(r'describing \S* (.*)$')
+UPDATE = re.compile(r'(update|error_update) (\S*) (.*)$')
+
+
+class EnumConvert(dict):
+    def __call__(self, value):
+        return float(self[value])
+
+
+class SecopStream(Stream):
+    ping_time = 0
+
+    def init(self):
+        self._buffer = []
+        print('send idn', 'tmo:', self.socket.timeout)
+        self.send('*IDN?')
+        resend = True
+        messages = []
+        for msg in self.get_lines():
+            if IDN.match(msg):
+                break
+            if resend:
+                self.send('*IDN?')
+                resend = False
+            messages.append(msg)
+        else:
+            raise ValueError(f'missing identifier, got {messages} instead')
+        self.send('describe')
+        for msg in self.get_lines():
+            match = DESCRIBING.match(msg)
+            if match:
+                break
+        else:
+            raise ValueError('missing describing message')
+        self.descr = json.loads(match.group(1))
+        self.device = self.descr['equipment_id']
+        if self.device.endswith('psi.ch'):
+            self.device[-6:] = []
+        self.tags['device'] = self.device
+        self.modules = self.descr['modules']
+        self.convert = {}
+        for mod, moddesc in self.modules.items():
+            for param, desc in moddesc['accessibles'].items():
+                dt = desc['datainfo']
+                if dt['type'] in ('double', 'int', 'enum'):
+                    self.convert[mod, param] = float
+        self.send('activate')
+
+    def ping(self):
+        self.send('ping')
+
+    def events(self):
+        try:
+            cnt = 0
+            for msg in self.get_lines():
+                match = UPDATE.match(msg)
+                if match:
+                    cmd, id, data = match.groups()
+                    key = tuple(id.split(':'))
+                    cvt = self.convert.get(key)
+                    if cvt:
+                        data = json.loads(data)
+                        if cmd == 'error_update':
+                            error = ': '.join(data[0:2])
+                            print(msg, repr(error))
+                            ts = data[2].get('t', time.time())
+                            value = None
+                        else:
+                            error = None
+                            ts = data[1].get('t', time.time())
+                            value = cvt(data[0])
+                        cnt += 1
+                        yield key, value, error, ts
+                elif msg == 'active':
+                    # from now on, no more waiting
+                    self.notimeout()
+            #print('SECOP', self.uri, 'cnt=', cnt)
+
+        except Exception as e:
+            print(self.uri, repr(e))
+
+
+SECOP_UDP_PORT = 10767
+
+
+class UdpStream(Base):
+    socket = None
+
+    def events(self):
+        while select([self.socket], [], [], 0.5)[0]:
+            try:
+                msg, addr = self.socket.recvfrom(1024)
+            except socket.error:  # pragma: no cover
+                return None
+            msg = json.loads(msg.decode('utf-8'))
+            if msg['SECoP'] != 'node':
+                continue
+            uri = f"{addr[0]}:{msg['port']}"
+            yield SecopStream, uri, msg['equipment_id']
+
+
+class ScanReply(UdpStream):
+    def __init__(self):
+        sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
+        sock.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, 1)
+        # send a general broadcast
+        try:
+            sock.sendto(json.dumps(dict(SECoP='discover')).encode('utf-8'),
+                        ('255.255.255.255', SECOP_UDP_PORT))
+        except OSError as e:
+            print('could not send the broadcast:', e)
+        self.socket = sock
+        self.select_dict[sock.fileno()] = self
+
+
+class ScanStream(UdpStream):
+    def __init__(self):
+        sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
+        sock.settimeout(1)
+        if os.name == 'nt':
+            sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
+        else:
+            sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEPORT, 1)
+        sock.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, 1)
+        sock.bind(('0.0.0.0', SECOP_UDP_PORT))
+        self.socket = sock
+        self.select_dict[sock.fileno()] = self
+
+
+
+