add normalize_uri instead of short_hostname

- use gethostbyaddr only in case of numeric IP
- hard wired reverse CNAME (network alias) for linse-c

normalizeuri.py

@@ -0,0 +1,35 @@
+import re
+import socket
+
+# sorry for hardwiring this ... there is no CNAME reverse lookup!
+# taking the original address as unique name would need a call to
+# gethostbyaddr, which might take some time - also not what we want
+reverse_alias = {
+    'pc15139': 'linse-c',
+    'pc16392': 'linse-a',
+}
+
+
+def normalizeuri(uri):
+    host, sep, port = uri.partition(':')
+    if host[0].isdigit():
+        try:
+            socket.setdefaulttimeout(1)
+            host = socket.gethostbyaddr(host)[0].split('.', 1)[0]
+        except socket.gaierror:
+            pass  # keep numbered IP
+        finally:
+            socket.setdefaulttimeout(None)
+    else:
+        host = host.split('.',1 )[0]
+    if host == 'localhost':
+        host = socket.gethostname()
+    else:
+        # this resolves CNAME entries (network aliases):
+        host = reverse_alias.get(host, host)
+    # strip appended IP when a host is registered twice (at PSI):
+    match = re.match(r'([^-]+)-129129\d{6}$', host)
+    host = match.group(1) if match else host
+    return f'{host}{sep}{port}'
+
+

secop.py

@@ -7,6 +7,7 @@ import logging
 from collections import namedtuple
 from select import select
 from streams import Stream, Base, StreamDead
+from normalizeuri import normalizeuri
 
 IDN = re.compile('.*ISSE.*,SEC[oO]P,')
 DESCRIBING = re.compile(r'describing \S* (.*)$')
@@ -139,7 +140,7 @@ class UdpStream(Base):
                 #     msg['device'] = uri.split('://', 1)[-1].split(':')[0]
                 kwargs = msg
             elif kind == 'node':
-                uri = f"{addr}:{msg['port']}"
+                uri = normalizeuri(f"{addr}:{msg['port']}")
                 kwargs = {'name': msg['equipment_id']}
             else:
                 continue

streams.py

@@ -3,6 +3,7 @@ import time
 import re
 import logging
 from select import select
+from normalizeuri import normalizeuri
 
 
 class StreamDead(Exception):
@@ -34,20 +35,6 @@ class Base:
         logging.info('FINISH BASE')
 
 
-def short_hostname(host):
-    """psi/lin/se special
-
-    - treat case where -129129xxxx is appended
-    """
-    host = socket.gethostbyaddr(host)[0]
-    if host == 'localhost':
-        host = socket.gethostname()
-    match = re.match(r'([^.-]+)(?:-129129\d{6}|(-[~.]*|)).psi.ch', host)
-    if match:
-        host = match.group(1) + (match.group(2) or '')
-    return host
-
-
 class Stream(Base):
     _last_time = None
     dead = False
@@ -82,10 +69,8 @@ class Stream(Base):
         self.socket = socket.create_connection(parse_uri(self.uri))
         self.select_read[self.socket.fileno()] = self
         self.settimeout(self.timeout)
-        host, _, port = self.uri.partition(':')
+        self.uri = self.tags['stream'] = f'{normalizeuri(self.uri)}'
-        # try to convert uri to host name
+        logging.info('connected %s', self.uri)
-        self.uri = self.tags['stream'] = f'{short_hostname(host)}:{port}'
-        logging.info('connected %s:%s = %s', host, port, self.uri)
         self._buffer = []
         self._deadline = INF
         self._next_connect = 0