Merge pull request #18 from l4m3rx/infinite-pings

Updated quiet and verbose_ping to generator objects for efficiency

ping.py

@@ -103,7 +103,7 @@ def _checksum(source_string):
 
 
 def single_ping(destIP, hostname, timeout, mySeqNumber, numDataBytes,
-           myStats=None, quiet=False, ipv6=False):
+                myStats=None, quiet=False, ipv6=False):
     """
     Returns either the delay (in ms) or None on timeout.
     """
@@ -319,6 +319,23 @@ def verbose_ping(hostname, timeout=3000, count=3,
     """
     Send >count< ping to >destIP< with the given >timeout< and display
     the result.
+
+    To continuously attempt ping requests, set >count< to None.
+
+    To consume the generator, use the following syntax:
+        >>> import ping
+        >>> for return_val in ping.verbose_ping('google.ca'):
+            pass  # COLLECT YIELDS AND PERFORM LOGIC.
+
+    Alternatively, you can consume the generator by using list comprehension:
+        >>> import ping
+        >>> consume = list(ping.verbose_ping('google.ca'))
+
+    Via the same syntax, you can successfully get the exit code via:
+        >>> import ping
+        >>> consume = list(ping.verbose_ping('google.ca'))
+        >>> exit_code = consume[:-1]  # The last yield is the exit code.
+        >>> sys.exit(exit_code)
     """
     signal.signal(signal.SIGINT, _signal_handler)  # Handle Ctrl-C
     if hasattr(signal, "SIGBREAK"):
@@ -344,9 +361,10 @@ def verbose_ping(hostname, timeout=3000, count=3,
 
     myStats.thisIP = destIP
 
-    for i in range(count):
+    i = 0
+    while 1:
         delay = single_ping(destIP, hostname, timeout, mySeqNumber,
-                       numDataBytes, ipv6=ipv6, myStats=myStats)
+                            numDataBytes, ipv6=ipv6, myStats=myStats)
         if delay is None:
             delay = 0
 
@@ -356,15 +374,23 @@ def verbose_ping(hostname, timeout=3000, count=3,
         if (MAX_SLEEP > delay):
             time.sleep((MAX_SLEEP - delay)/1000)
 
+        if count is not None and i < count:
+            i += 1
+            yield myStats.pktsRcvd
+        elif count is None:
+            yield myStats.pktsRcvd
+        elif count is not None and i >= count:
+            break
+
     _dump_stats(myStats)
     # 0 if we receive at least one packet
     # 1 if we don't receive any packets
-    return not myStats.pktsRcvd
+    yield not myStats.pktsRcvd
 
 
 def quiet_ping(hostname, timeout=3000, count=3,
                numDataBytes=64, path_finder=False, ipv6=False):
-    """ Same as verbose_ping, but the results are returned as tuple """
+    """ Same as verbose_ping, but the results are yielded as a tuple """
     myStats = MyStats()  # Reset the stats
     mySeqNumber = 0  # Starting value
 
@@ -375,7 +401,7 @@ def quiet_ping(hostname, timeout=3000, count=3,
         else:
             destIP = socket.gethostbyname(hostname)
     except socket.gaierror:
-        return False
+        yield False
 
     myStats.thisIP = destIP
 
@@ -385,12 +411,14 @@ def quiet_ping(hostname, timeout=3000, count=3,
     if path_finder:
         fakeStats = MyStats()
         single_ping(fakeStats, destIP, hostname, timeout,
-               mySeqNumber, numDataBytes, quiet=True, ipv6=ipv6)
+                    mySeqNumber, numDataBytes, quiet=True, ipv6=ipv6)
         time.sleep(0.5)
 
-    for i in range(count):
-        delay = single_ping(destIP, hostname, timeout, mySeqNumber, numDataBytes,
-                       quiet=True, ipv6=ipv6, myStats=myStats)
+    i = 0
+    while 1:
+        delay = single_ping(destIP, hostname, timeout, mySeqNumber,
+                            numDataBytes, quiet=True, ipv6=ipv6,
+                            myStats=myStats)
 
         if delay is None:
             delay = 0
@@ -401,6 +429,15 @@ def quiet_ping(hostname, timeout=3000, count=3,
         if (MAX_SLEEP > delay):
             time.sleep((MAX_SLEEP - delay) / 1000)
 
+        yield myStats.pktsSent
+
+        if count is not None and i < count:
+            i += 1
+        elif count is not None:
+            yield myStats.pktsSent
+        elif count is not None and i >= count:
+            break
+
     if myStats.pktsSent > 0:
         myStats.fracLoss = (myStats.pktsSent - myStats.pktsRcvd) / \
             myStats.pktsSent
@@ -409,32 +446,42 @@ def quiet_ping(hostname, timeout=3000, count=3,
         myStats.avrgTime = myStats.totTime / myStats.pktsRcvd
 
     # return tuple(max_rtt, min_rtt, avrg_rtt, percent_lost)
-    return myStats.maxTime, myStats.minTime, myStats.avrgTime, myStats.fracLoss
+    yield myStats.maxTime, myStats.minTime, myStats.avrgTime, myStats.fracLoss
 
 
 if __name__ == '__main__':
     # FIXME: Add a real CLI (mostly fixed)
     if sys.argv.count('-T') or sys.argv.count('--test_case'):
         print('Running PYTHON PING test case.')
         # These should work:
-        verbose_ping("127.0.0.1")
-        verbose_ping("8.8.8.8")
-        verbose_ping("heise.de")
-        verbose_ping("google.com")
+        for val in verbose_ping("127.0.0.1"):
+            pass
+        for val in verbose_ping("8.8.8.8"):
+            pass
+        for val in verbose_ping("heise.de"):
+            pass
+        for val in verbose_ping("google.com"):
+            pass
 
         # Inconsistent on Windows w/ ActivePython (Python 3.2 resolves
         # correctly to the local host, but 2.7 tries to resolve to the local
         # *gateway*)
-        verbose_ping("localhost")
+        for val in verbose_ping("localhost"):
+            pass
 
         # Should fail with 'getaddrinfo failed':
-        verbose_ping("foobar_url.foobar")
+        for val in verbose_ping("foobar_url.fooobar"):
+            pass
 
         # Should fail (timeout), but it depends on the local network:
-        verbose_ping("192.168.255.254")
+        for val in verbose_ping("192.168.255.254"):
+            pass
 
         # Should fails with 'The requested address is not valid in its context'
-        verbose_ping("0.0.0.0")
+        for val in verbose_ping("0.0.0.0"):
+            pass
+
+        exit()
 
     parser = argparse.ArgumentParser(prog='python-ping',
                                      description='A pure python implementation\
@@ -447,7 +494,9 @@ def quiet_ping(hostname, timeout=3000, count=3,
     parser.add_argument('-c', '--request_count', help='The number of attempts \
                         to make. See --infinite to attempt requests until \
                         stopped.', type=int, default=3)
-    # TODO Implement the ability to continuously attempt pings.
+
+    parser.add_argument('-i', '--infinite', help='Flag to continuously ping \
+                        a host until stopped.', action='store_true')
 
     parser.add_argument('-I', '--ipv6', action='store_true', help='Flag to \
                         use IPv6.')
@@ -460,5 +509,12 @@ def quiet_ping(hostname, timeout=3000, count=3,
 
     parsed = parser.parse_args()
 
-    sys.exit(verbose_ping(parsed.address, parsed.timeout, parsed.request_count,
-                          parsed.packet_size, ipv6=parsed.ipv6))
+    if parsed.infinite:
+        sys.exit(list(verbose_ping(parsed.address, parsed.timeout,
+                                   None, parsed.packet_size,
+                                   ipv6=parsed.ipv6))[:-1])
+
+    else:
+        sys.exit(list(verbose_ping(parsed.address, parsed.timeout,
+                                   parsed.request_count, parsed.packet_size,
+                                   ipv6=parsed.ipv6))[:-1])