diff --git a/broadview_lib/config/agentapi.py b/broadview_lib/config/agentapi.py
index 128c834..c58caa5 100644
--- a/broadview_lib/config/agentapi.py
+++ b/broadview_lib/config/agentapi.py
@@ -15,9 +15,12 @@
import json
from collections import OrderedDict
from agentconnection import AgentConnection
+from broadviewconfig import BroadViewLibConfig
+import fcntl
class AgentAPI(object):
- __serial = 1
+ __serial = None
+ __cfg = BroadViewLibConfig()
def __init__(self):
self.__httpMethod = "POST"
self.__feature = None
@@ -55,6 +58,88 @@ class AgentAPI(object):
if self.__payload:
ret = self.__payload["method"]
return ret
+
+ def getLastUsedSerial(self):
+ '''
+ Some requests to the agent, like PT's get lag resolution with a
+ non-zero collection interval, require knowlege of the JSON RPC
+ serial number because it is used as a key/index for later
+ cancelling the collection. While this violates layering, this is
+ no big deal if only one client (or client instance) ever connects
+ to an agent in the data center, and the client never generates
+ (within reason) a request with a duplicate ID that maps to an ID
+ used by the agent as an index.
+
+ When multiple clients, or even clients that are restarted enter
+ the picture, requiring clients to generate IDs that are
+ unique across applications and hosts is obviously more difficult.
+ Such difficulties are communication among clients within
+ the datacenter to ensure that no client uses the same IDs as any
+ other, and requiring each client to persist the last used ID in
+ case of crash or restart.
+
+ The strategy we take here to deal with this is to use a file to
+ store the last used ID, and protect that file with a SYSV file
+ lock. If a client wants to make a request, the lock is acquired,
+ the last used ID is read from the file, the ID is incremented by
+ 1 and the file rewritten, followed by release of the lock. Sharing
+ across nodes in the datacenter can be acheived by all hosts using
+ a lock file that is located in shared filesystem location, such
+ as NFS.
+
+ Obviously all apps on a host or within the datacenter that access
+ a given agent must use the same ID file. If there are multiple agents
+ in the datacenter (which is going to be the case, as no interesting
+ datacenter is going to have one switch), there must be one (and only
+ one) id file per switch/agent.
+
+ We can eliminate this need for request ID management once the
+ agent adopts a method where it allocates and returns handles for
+ objects and tasks that it is managing to be used by clients to
+ refer to those same objects and tasks in subsequent requests.
+
+ This function exposes the last used ID so that the client can use
+ it in a subsequent (cancellation) request.
+
+
+ '''
+
+ return AgentAPI.__serial
+
+ def getIDFileLocation(self):
+ return AgentAPI.__cfg.getRequestIDFile()
+
+ def getNextSerial(self):
+
+ '''
+ Get the next request ID, updating the shared ID file. The name
+ of the ID file comes from a configuration file named
+ /etc/broadviewlib.conf via a setting named json_rpc_id_path. Here
+ is an example conf file that sets the ID file path to /tmp/foo.txt:
+
+ [misc]
+
+ json_rpc_id_path = /tmp/foo.txt
+
+ '''
+
+ filename = self.getIDFileLocation()
+
+ f = open(filename, "a").close() # create if needed
+ f = open(filename, "r+")
+ fd = f.fileno()
+ fcntl.lockf(fd, fcntl.LOCK_EX)
+ serial = f.read()
+ if len(serial) == 0:
+ serial = 1 # new file, read zero bytes, so initialize
+ else:
+ serial = int(serial)
+ f.seek(0)
+ f.write("{}".format(serial + 1))
+ fcntl.lockf(fd, fcntl.LOCK_UN)
+ f.close()
+ AgentAPI.__serial = serial # XXX not thread safe
+ return serial
def _send(self, o, timeout):
self.__payload = {}
@@ -62,8 +147,7 @@ class AgentAPI(object):
self.__payload["asic-id"] = o["asic-id"]
self.__payload["method"] = o["method"]
self.__payload["params"] = o["params"]
- self.__payload["id"] = AgentAPI.__serial
- AgentAPI.__serial = AgentAPI.__serial + 1
+ self.__payload["id"] = self.getNextSerial()
conn = AgentConnection(self.__host, self.__port, self.__feature, timeout)
r = conn.makeRequest(self)
conn.close()
diff --git a/broadview_lib/config/broadviewconfig.py b/broadview_lib/config/broadviewconfig.py
index f90fd66..a5e9873 100644
--- a/broadview_lib/config/broadviewconfig.py
+++ b/broadview_lib/config/broadviewconfig.py
@@ -16,6 +16,27 @@ import ConfigParser
import json
import unittest
+class BroadViewLibConfig():
+ cfg = None
+
+ def __init__(self):
+ if not BroadViewLibConfig.cfg:
+ try:
+ BroadViewLibConfig.cfg = ConfigParser.ConfigParser()
+ BroadViewLibConfig.cfg.read("/etc/broadviewlib.conf")
+ except:
+ BroadViewLibConfig.cfg = None
+ pass
+
+ def getRequestIDFile(self):
+ ret = "/tmp/bvserial.txt"
+ try:
+ ret = BroadViewLibConfig.cfg.get("misc", "json_rpc_id_path")
+ except:
+ pass
+
+ return ret
+
class BroadViewBSTSwitches():
cfg = None
bst_switches = None
diff --git a/broadview_lib/config/pt.py b/broadview_lib/config/pt.py
index 52b2502..dccb4cd 100644
--- a/broadview_lib/config/pt.py
+++ b/broadview_lib/config/pt.py
@@ -343,6 +343,8 @@ class GetPacketTraceLAGResolution(AgentAPI):
rep = None
if status == 200:
self.__json = json["report"]
+ print self.__json
+ self.__json[0]["cancellation-id"] = self.getLastUsedSerial()
rep = PTParser()
rep.process(json)
else:
@@ -402,6 +404,7 @@ class GetPacketTraceECMPResolution(AgentAPI):
rep = None
if status == 200:
self.__json = json["report"]
+ self.__json[0]["cancellation-id"] = self.getLastUsedSerial()
rep = PTParser()
rep.process(json)
else:
@@ -461,6 +464,7 @@ class GetPacketTraceProfile(AgentAPI):
rep = None
if status == 200:
self.__json = json["report"]
+ self.__json[0]["cancellation-id"] = self.getLastUsedSerial()
rep = PTParser()
rep.process(json)
else:
diff --git a/broadview_lib/tools/bv-ptctl.py b/broadview_lib/tools/bv-ptctl.py
index b39b979..aef4f4d 100644
--- a/broadview_lib/tools/bv-ptctl.py
+++ b/broadview_lib/tools/bv-ptctl.py
@@ -236,10 +236,24 @@ class PTCommand():
def handleCancelProfile(self, args):
usage = False
+ reqid = None
usage, asic, host, port = self.getASICHostPort(args)
+ if not usage:
+ for arg in args:
+ if "id:" in arg:
+ v = arg.split(":")
+ if len(v) == 2:
+ reqid = int(v[1])
+ else:
+ print "invalid id: bad argument count"
+ usage = True
+ if reqid == None:
+ print "missing id argument"
+ usage = True
if not usage:
x = CancelPacketTraceProfile(host, port)
x.setASIC(asic)
+ x.setId(reqid)
status = x.send(self._timeout)
if status != 200:
print "failure: {}".format(status)
@@ -249,13 +263,31 @@ class PTCommand():
def helpCancelProfile(self, name):
print name
+ print
+ print "args:"
+ print
+ print " id:id (see cancellation-id output from get-profile command)"
+ print " id:id"
def handleCancelLAGResolution(self, args):
usage = False
+ reqid = None
usage, asic, host, port = self.getASICHostPort(args)
+ if not usage:
+ for arg in args:
+ if "id:" in arg:
+ v = arg.split(":")
+ if len(v) == 2:
+ reqid = int(v[1])
+ else:
+ print "invalid id: bad argument count"
+ usage = True
+ if reqid == None:
+ print "missing id argument"
if not usage:
x = CancelPacketTraceLAGResolution(host, port)
x.setASIC(asic)
+ x.setId(reqid)
status = x.send(self._timeout)
if status != 200:
print "failure: {}".format(status)
@@ -265,13 +297,30 @@ class PTCommand():
def helpCancelLAGResolution(self, name):
print name
+ print
+ print "args:"
+ print
+ print " id:id (see cancellation-id output from get-lag-resolution command"
def handleCancelECMPResolution(self, args):
usage = False
+ reqid = None
usage, asic, host, port = self.getASICHostPort(args)
+ if not usage:
+ for arg in args:
+ if "id:" in arg:
+ v = arg.split(":")
+ if len(v) == 2:
+ reqid = int(v[1])
+ else:
+ print "invalid id: bad argument count"
+ usage = True
+ if reqid == None:
+ print "missing id argument"
if not usage:
x = CancelPacketTraceECMPResolution(host, port)
x.setASIC(asic)
+ x.setId(reqid)
status = x.send(self._timeout)
if status != 200:
print "failure: {}".format(status)
@@ -281,6 +330,10 @@ class PTCommand():
def helpCancelECMPResolution(self, name):
print name
+ print
+ print "args:"
+ print
+ print " id:id (see cancellation-id output from get-ecmp-resolution command"
def handleCancelSendDropPacket(self, args):
usage = False
@@ -450,6 +503,10 @@ class PTCommand():
print " port-list:port[,port][,port]...[,port]"
print " collection-interval: interval"
print " drop-packet: [0|1]"
+ print
+ print "notes:"
+ print
+ print " use the cancellation-id output as id arg for cancel-lag-resolution command to cancel when collection-interval non-zero"
def handleGetECMPResolution(self, args):
usage = False
@@ -510,6 +567,10 @@ class PTCommand():
print " port-list:port[,port][,port]...[,port]"
print " collection-interval: interval"
print " drop-packet: [0|1]"
+ print
+ print "notes:"
+ print
+ print " use the cancellation-id output as id arg for cancel-ecmp-resolution command to cancel when collection-interval non-zero"
def handleGetProfile(self, args):
usage = False
@@ -575,6 +636,10 @@ class PTCommand():
print " port-list:port[,port][,port]...[,port]"
print " collection-interval: interval"
print " drop-packet: [0|1]"
+ print
+ print "notes:"
+ print
+ print " use the cancellation-id output as id arg for cancel-profile command to cancel when collection-interval non-zero"
def handleGetDropReason(self, args):
usage = False