Merge branch 'socket_api'

.gitignore

@@ -6,3 +6,5 @@ __pycache__/
 /env/
 
 current.ospf
+
+/venv/

birdvisu/maps_new/__init__.py

@@ -144,7 +144,7 @@ class AnnotatedTopology:
 # TODO: maybe class to handle sets of annotators?
 def annotate_topology(topology,
 					annotators: Sequence[Callable[[AnnotatedTopology], AnnotatedTopology]],
-					initial_annotation: AnnotatedTopology = None,
+					initial_annotation: AnnotatedTopology | None = None,
 					) -> AnnotatedTopology:
 	"""Runs all the annotators and assigns all the tags.
 

birdvisu/maps_new/providers.py

@@ -1,6 +1,6 @@
 """Common TopologyProviders"""
 
-from birdvisu import ospffile
+from birdvisu import ospffile, ospfsock
 from birdvisu.maps_new import TopologyProvider, Router, Network, Link, Topology
 import subprocess
 import re
@@ -16,7 +16,7 @@ class OspfDataTopologyProvider(TopologyProvider):
 		# feel trustworthy (I don't really understand them, but I think they
 		# depend on designated routers and interface numbers, changes of which
 		# should not cause us to think that is a different network)
-		self.network_renames = {}
+		self.network_renames : dict[str,str] = {}
 		# We only care for areas:
 		# TODO: Should we support global visualisation configuration?
 		for directive, details in parsed:
@@ -125,3 +125,15 @@ class RunningBirdTopologyProvider(TopologyProvider):
 
 	def get_topology(self):
 		return self.topology
+
+class BirdSocketTopologyProvider(TopologyProvider):
+	"""This one is dynamic, provides new topology every time."""
+	def __init__(self, socket_filename='/run/bird/bird.ctl'):
+		self.socket_filename = socket_filename
+	
+	def get_topology(self):
+		birdsock = ospfsock.BirdSocketConnection()
+		resp = birdsock.request('show ospf state')
+		# TODO: Naming things – this is not exactly parser…
+		parser = OspfDataTopologyProvider(resp.text)
+		return parser.get_topology()

birdvisu/ospfsock.py

@@ -0,0 +1,82 @@
+"""Simple utility to interface with BIRD using the control socket."""
+
+from dataclasses import dataclass,field
+import socket as sk
+from string import digits
+
+class BirdError(Exception):
+	def __init__(self, code, where, text):
+		self.code = code
+		self.start = where[0]
+		self.end = where[1]
+		self.text = text
+
+@dataclass
+class BirdResponse:
+	text: str = ''
+	codes: list[tuple[tuple[int, int], str]] = field(default_factory=list) # List of line ranges (inclusive) and the respective code.
+
+	def raise_exceptions(self) -> None:
+		# If the response contains any errors, raise them as BirdErrors
+		# TODO Py3.11: use ExceptionGroups?
+		# Until then, let's just report the first one?
+		assert len(self.codes) >= 1, "Not a valid response."
+		for where, code in self.codes:
+			if code.startswith('9'):
+				# Extract text
+				start = where[0] - 1
+				end = where[1]
+				print(start,end)
+				errorlines = self.text.splitlines(keepends=True)[start:end]
+				exc = BirdError(code, where, ''.join(errorlines))
+				raise exc
+
+class BirdSocketConnection:
+	def __init__(self, sockpath='/run/bird/bird.ctl'):
+		self.socket = sk.socket(sk.AF_UNIX, sk.SOCK_STREAM)
+		self.socket.setblocking(False)
+		self.socket.connect(sockpath)
+		# Bird announces itself by printing version. We save the response just in case.
+		self.bird_prologue = self._parse_response()
+
+	def request(self, req: str) -> BirdResponse:
+		if not req.endswith('\n'):
+			req = req + '\n'
+		binreq = req.encode()
+		self.socket.send(binreq)
+		return self._parse_response()
+
+	def _parse_response(self) -> BirdResponse:
+		# We even read from the socket here in order to have the whole protocol
+		# described at one place. Therefore other parts of the code do not need
+		# to know anything about the protocol (maybe apart from the meaning of
+		# status codes, if they are interested…)
+		result = BirdResponse()
+		code : str | None = None # string because of leading zeroes, and it has no numeric interpretation anyway
+		start = None
+		cont = True
+		f = self.socket.makefile('r')
+		for i, line in enumerate(f, start=1):
+			assert cont, "WTF bad format (should not continue)."
+			if line.startswith(tuple(digits)):
+				if start is not None:
+					end = i-1
+					result.codes.append(((start, end), code))
+				code = line[:4]
+				start = i
+				cont = line[4] == '-'
+				text = line[5:]
+			else:
+				assert cont == True
+				text = line[1:]
+			result.text += text # Invariant: LF as line terminator
+			if not cont:
+				# Finalization. We do not have i after the end of the cycle,
+				# but this is the last iteration.
+				end = i
+				result.codes.append(((start, end), code))
+				break
+		result.raise_exceptions()
+		return result
+
+

poor_mans_visualisation.py

@@ -14,7 +14,7 @@ with open(ref_topo_file) as ref_file:
 	ref_topo = providers.OspfFileTopologyProvider(ref_file).get_topology()
 
 try:
-	cur_topo = providers.RunningBirdTopologyProvider().get_topology()
+	cur_topo = providers.BirdSocketTopologyProvider().get_topology()
 except OSError:
 	# HACK!
 	import traceback as tb
@@ -95,6 +95,16 @@ for tagsrc in [
 		scene.addItem(taglist[-1])
 
 view = QtWidgets.QGraphicsView(scene)
-view.show()
+#view.show()
+
+
+main_window = QtWidgets.QMainWindow()
+main_window.setCentralWidget(view)
+
+menu = main_window.menuBar().addMenu('Hello')
+act = QtGui.QAction('Hi')
+#act.setToolTip('Howdy')
+menu.addAction(act)
+main_window.show()
 
 app.exec()