papi: lazily initialize stats client

remove wait-loop on stats socket from test framework.

Type: refactor

Change-Id: I5bb95a7c597707a87f9d9a471215c4b4af1a2280
Signed-off-by: Paul Vinciguerra <pvinci@vinciconsulting.com>

src/vpp-api/python/vpp_papi/vpp_stats.py

@@ -196,34 +196,46 @@ class VPPStats(object):
     sharedlib_name = 'libvppapiclient.so'
 
     def __init__(self, socketname=default_socketname, timeout=10):
+        self.socketname = socketname
+        self.timeout = timeout
+        self.connected = False
         try:
             self.api = ffi.dlopen(VPPStats.sharedlib_name)
         except Exception:
             raise VPPStatsClientLoadError("Could not open: %s" %
                                           VPPStats.sharedlib_name)
+
+    def connect(self):
         self.client = self.api.stat_client_get()
 
-        poll_end_time = time.time() + timeout
+        poll_end_time = time.time() + self.timeout
         while time.time() < poll_end_time:
-            rv = self.api.stat_segment_connect_r(socketname.encode('utf-8'),
-                                                 self.client)
+            rv = self.api.stat_segment_connect_r(
+                self.socketname.encode('utf-8'), self.client)
             # Break out if success or any other error than "no such file"
             # (indicating that VPP hasn't started yet)
             if rv == 0 or ffi.errno != 2:
+                self.connected = True
                 break
 
         if rv != 0:
             raise VPPStatsIOError(retval=rv)
 
     def heartbeat(self):
+        if not self.connected:
+            self.connect()
         return self.api.stat_segment_heartbeat_r(self.client)
 
     def ls(self, patterns):
+        if not self.connected:
+            self.connect()
         return self.api.stat_segment_ls_r(make_string_vector(self.api,
                                                              patterns),
                                           self.client)
 
     def lsstr(self, patterns):
+        if not self.connected:
+            self.connect()
         rv = self.api.stat_segment_ls_r(make_string_vector(self.api,
                                                            patterns),
                                         self.client)
@@ -235,6 +247,8 @@ class VPPStats(object):
                 for i in range(self.api.stat_segment_vec_len(rv))]
 
     def dump(self, counters):
+        if not self.connected:
+            self.connect()
         stats = {}
         rv = self.api.stat_segment_dump_r(counters, self.client)
         # Raise exception and retry
@@ -271,8 +285,14 @@ class VPPStats(object):
         return sum(self.get_counter(name))
 
     def disconnect(self):
-        self.api.stat_segment_disconnect_r(self.client)
-        self.api.stat_client_free(self.client)
+        try:
+            self.api.stat_segment_disconnect_r(self.client)
+            self.api.stat_client_free(self.client)
+            self.connected = False
+            del self.client
+        except AttributeError:
+            # no need to disconnect if we're not connected
+            pass
 
     def set_errors(self):
         '''Return all errors counters > 0'''

test/framework.py

@@ -462,19 +462,6 @@ class VppTestCase(unittest.TestCase):
 
         cls.wait_for_enter()
 
-    @classmethod
-    def wait_for_stats_socket(cls):
-        deadline = time.time() + 300
-        ok = False
-        while time.time() < deadline or \
-                cls.debug_gdb or cls.debug_gdbserver:
-            if os.path.exists(cls.stats_sock):
-                ok = True
-                break
-            cls.sleep(0.8)
-        if not ok:
-            cls.logger.critical("Couldn't stat : {}".format(cls.stats_sock))
-
     @classmethod
     def wait_for_coredump(cls):
         corefile = cls.tempdir + "/core"
@@ -560,7 +547,6 @@ class VppTestCase(unittest.TestCase):
             else:
                 hook = hookmodule.PollHook(cls)
             cls.vapi.register_hook(hook)
-            cls.wait_for_stats_socket()
             cls.statistics = VPPStats(socketname=cls.stats_sock)
             try:
                 hook.poll_vpp()