daemon: added link option to configure buffer, added support in pygui to allow configuring buffer

daemon/core/api/grpc/grpcutils.py

@@ -128,6 +128,7 @@ def add_link_data(
         options.mer = options_proto.mer
         options.burst = options_proto.burst
         options.mburst = options_proto.mburst
+        options.buffer = options_proto.buffer
         options.unidirectional = options_proto.unidirectional
         options.key = options_proto.key
     return iface1_data, iface2_data, options, link_type
@@ -329,6 +330,7 @@ def convert_link_options(options_data: LinkOptions) -> core_pb2.LinkOptions:
         burst=options_data.burst,
         delay=options_data.delay,
         dup=options_data.dup,
+        buffer=options_data.buffer,
         unidirectional=options_data.unidirectional,
     )
 

daemon/core/api/grpc/server.py

@@ -972,6 +972,7 @@ class CoreGrpcServer(core_pb2_grpc.CoreApiServicer):
             mburst=options_proto.mburst,
             unidirectional=options_proto.unidirectional,
             key=options_proto.key,
+            buffer=options_proto.buffer,
         )
         session.update_link(node1_id, node2_id, iface1_id, iface2_id, options)
         iface1 = InterfaceData(id=iface1_id)

daemon/core/api/grpc/wrappers.py

@@ -457,6 +457,7 @@ class LinkOptions:
     delay: int = 0
     dup: int = 0
     unidirectional: bool = False
+    buffer: int = 0
 
     @classmethod
     def from_proto(cls, proto: core_pb2.LinkOptions) -> "LinkOptions":
@@ -471,6 +472,7 @@ class LinkOptions:
             delay=proto.delay,
             dup=proto.dup,
             unidirectional=proto.unidirectional,
+            buffer=proto.buffer,
         )
 
     def to_proto(self) -> core_pb2.LinkOptions:
@@ -485,6 +487,7 @@ class LinkOptions:
             delay=self.delay,
             dup=self.dup,
             unidirectional=self.unidirectional,
+            buffer=self.buffer,
         )
 
 

daemon/core/emulator/data.py

@@ -172,6 +172,7 @@ class LinkOptions:
     mburst: int = None
     unidirectional: int = None
     key: int = None
+    buffer: int = None
 
 
 @dataclass

daemon/core/gui/dialogs/linkconfig.py

@@ -49,12 +49,14 @@ class LinkConfigurationDialog(Dialog):
         self.jitter: tk.StringVar = tk.StringVar()
         self.loss: tk.StringVar = tk.StringVar()
         self.duplicate: tk.StringVar = tk.StringVar()
+        self.buffer: tk.StringVar = tk.StringVar()
 
         self.down_bandwidth: tk.StringVar = tk.StringVar()
         self.down_delay: tk.StringVar = tk.StringVar()
         self.down_jitter: tk.StringVar = tk.StringVar()
         self.down_loss: tk.StringVar = tk.StringVar()
         self.down_duplicate: tk.StringVar = tk.StringVar()
+        self.down_buffer: tk.StringVar = tk.StringVar()
 
         self.color: tk.StringVar = tk.StringVar(value=self.edge.color)
         self.color_button: Optional[tk.Button] = None
@@ -187,6 +189,19 @@ class LinkConfigurationDialog(Dialog):
             entry.grid(row=row, column=2, sticky=tk.EW, pady=PADY)
         row = row + 1
 
+        label = ttk.Label(frame, text="Buffer (Packets)")
+        label.grid(row=row, column=0, sticky=tk.EW)
+        entry = validation.PositiveIntEntry(
+            frame, empty_enabled=False, textvariable=self.buffer
+        )
+        entry.grid(row=row, column=1, sticky=tk.EW, pady=PADY)
+        if not self.is_symmetric:
+            entry = validation.PositiveIntEntry(
+                frame, empty_enabled=False, textvariable=self.down_buffer
+            )
+            entry.grid(row=row, column=2, sticky=tk.EW, pady=PADY)
+        row = row + 1
+
         label = ttk.Label(frame, text="Color")
         label.grid(row=row, column=0, sticky=tk.EW)
         self.color_button = tk.Button(
@@ -224,9 +239,15 @@ class LinkConfigurationDialog(Dialog):
         jitter = get_int(self.jitter)
         delay = get_int(self.delay)
         duplicate = get_int(self.duplicate)
+        buffer = get_int(self.buffer)
         loss = get_float(self.loss)
         options = LinkOptions(
-            bandwidth=bandwidth, jitter=jitter, delay=delay, dup=duplicate, loss=loss
+            bandwidth=bandwidth,
+            jitter=jitter,
+            delay=delay,
+            dup=duplicate,
+            loss=loss,
+            buffer=buffer,
         )
         link.options = options
         iface1_id = link.iface1.id if link.iface1 else None
@@ -243,6 +264,7 @@ class LinkConfigurationDialog(Dialog):
             down_jitter = get_int(self.down_jitter)
             down_delay = get_int(self.down_delay)
             down_duplicate = get_int(self.down_duplicate)
+            down_buffer = get_int(self.down_buffer)
             down_loss = get_float(self.down_loss)
             options = LinkOptions(
                 bandwidth=down_bandwidth,
@@ -250,6 +272,7 @@ class LinkConfigurationDialog(Dialog):
                 delay=down_delay,
                 dup=down_duplicate,
                 loss=down_loss,
+                buffer=down_buffer,
                 unidirectional=True,
             )
             self.edge.asymmetric_link = Link(
@@ -304,6 +327,7 @@ class LinkConfigurationDialog(Dialog):
             self.duplicate.set(str(link.options.dup))
             self.loss.set(str(link.options.loss))
             self.delay.set(str(link.options.delay))
+            self.buffer.set(str(link.options.buffer))
         if not self.is_symmetric:
             asym_link = self.edge.asymmetric_link
             self.down_bandwidth.set(str(asym_link.options.bandwidth))
@@ -311,3 +335,4 @@ class LinkConfigurationDialog(Dialog):
             self.down_duplicate.set(str(asym_link.options.dup))
             self.down_loss.set(str(asym_link.options.loss))
             self.down_delay.set(str(asym_link.options.delay))
+            self.down_buffer.set(str(asym_link.options.buffer))

daemon/core/nodes/network.py

@@ -456,6 +456,7 @@ class CoreNetwork(CoreNetworkBase):
                 iface.setparam("loss", options.loss),
                 iface.setparam("duplicate", options.dup),
                 iface.setparam("jitter", options.jitter),
+                iface.setparam("buffer", options.buffer),
             ]
         )
         if not changed:
@@ -470,6 +471,7 @@ class CoreNetwork(CoreNetworkBase):
                 options.loss is None or options.loss <= 0,
                 options.dup is None or options.dup <= 0,
                 options.bandwidth is None or options.bandwidth <= 0,
+                options.buffer is None or options.buffer <= 0,
             ]
         ):
             if not iface.getparam("has_netem"):
@@ -483,7 +485,9 @@ class CoreNetwork(CoreNetworkBase):
             if options.bandwidth is not None:
                 limit = 1000
                 bw = options.bandwidth / 1000
-                if options.delay and options.bandwidth:
+                if options.buffer is not None and options.buffer > 0:
+                    limit = options.buffer
+                elif options.delay and options.bandwidth:
                     delay = options.delay / 1000
                     limit = max(2, math.ceil((2 * bw * delay) / (8 * iface.mtu)))
                 netem += f" rate {bw}kbit"

daemon/proto/core/api/grpc/core.proto

@@ -777,6 +777,7 @@ message LinkOptions {
     int64 delay = 8;
     int32 dup = 9;
     bool unidirectional = 10;
+    int32 buffer = 11;
 }
 
 message Interface {

daemon/tests/test_links.py

@@ -83,6 +83,7 @@ class TestLinks:
         loss = 25
         dup = 25
         jitter = 10
+        buffer = 100
         node1 = session.add_node(CoreNode)
         node2 = session.add_node(SwitchNode)
         iface1_data = ip_prefixes.create_iface(node1)
@@ -93,10 +94,16 @@ class TestLinks:
         assert iface1.getparam("loss") != loss
         assert iface1.getparam("duplicate") != dup
         assert iface1.getparam("jitter") != jitter
+        assert iface1.getparam("buffer") != buffer
 
         # when
         options = LinkOptions(
-            delay=delay, bandwidth=bandwidth, loss=loss, dup=dup, jitter=jitter
+            delay=delay,
+            bandwidth=bandwidth,
+            loss=loss,
+            dup=dup,
+            jitter=jitter,
+            buffer=buffer,
         )
         session.update_link(
             node1.id, node2.id, iface1_id=iface1_data.id, options=options
@@ -108,6 +115,7 @@ class TestLinks:
         assert iface1.getparam("loss") == loss
         assert iface1.getparam("duplicate") == dup
         assert iface1.getparam("jitter") == jitter
+        assert iface1.getparam("buffer") == buffer
 
     def test_update_net_to_node(self, session: Session, ip_prefixes: IpPrefixes):
         # given
@@ -116,6 +124,7 @@ class TestLinks:
         loss = 25
         dup = 25
         jitter = 10
+        buffer = 100
         node1 = session.add_node(SwitchNode)
         node2 = session.add_node(CoreNode)
         iface2_data = ip_prefixes.create_iface(node2)
@@ -126,10 +135,16 @@ class TestLinks:
         assert iface2.getparam("loss") != loss
         assert iface2.getparam("duplicate") != dup
         assert iface2.getparam("jitter") != jitter
+        assert iface2.getparam("buffer") != buffer
 
         # when
         options = LinkOptions(
-            delay=delay, bandwidth=bandwidth, loss=loss, dup=dup, jitter=jitter
+            delay=delay,
+            bandwidth=bandwidth,
+            loss=loss,
+            dup=dup,
+            jitter=jitter,
+            buffer=buffer,
         )
         session.update_link(
             node1.id, node2.id, iface2_id=iface2_data.id, options=options
@@ -141,6 +156,7 @@ class TestLinks:
         assert iface2.getparam("loss") == loss
         assert iface2.getparam("duplicate") == dup
         assert iface2.getparam("jitter") == jitter
+        assert iface2.getparam("buffer") == buffer
 
     def test_update_ptp(self, session: Session, ip_prefixes: IpPrefixes):
         # given
@@ -149,6 +165,7 @@ class TestLinks:
         loss = 25
         dup = 25
         jitter = 10
+        buffer = 100
         node1 = session.add_node(CoreNode)
         node2 = session.add_node(CoreNode)
         iface1_data = ip_prefixes.create_iface(node1)
@@ -161,15 +178,22 @@ class TestLinks:
         assert iface1.getparam("loss") != loss
         assert iface1.getparam("duplicate") != dup
         assert iface1.getparam("jitter") != jitter
+        assert iface1.getparam("buffer") != buffer
         assert iface2.getparam("delay") != delay
         assert iface2.getparam("bw") != bandwidth
         assert iface2.getparam("loss") != loss
         assert iface2.getparam("duplicate") != dup
         assert iface2.getparam("jitter") != jitter
+        assert iface2.getparam("buffer") != buffer
 
         # when
         options = LinkOptions(
-            delay=delay, bandwidth=bandwidth, loss=loss, dup=dup, jitter=jitter
+            delay=delay,
+            bandwidth=bandwidth,
+            loss=loss,
+            dup=dup,
+            jitter=jitter,
+            buffer=buffer,
         )
         session.update_link(node1.id, node2.id, iface1_data.id, iface2_data.id, options)
 
@@ -179,11 +203,13 @@ class TestLinks:
         assert iface1.getparam("loss") == loss
         assert iface1.getparam("duplicate") == dup
         assert iface1.getparam("jitter") == jitter
+        assert iface1.getparam("buffer") == buffer
         assert iface2.getparam("delay") == delay
         assert iface2.getparam("bw") == bandwidth
         assert iface2.getparam("loss") == loss
         assert iface2.getparam("duplicate") == dup
         assert iface2.getparam("jitter") == jitter
+        assert iface2.getparam("buffer") == buffer
 
     def test_delete_ptp(self, session: Session, ip_prefixes: IpPrefixes):
         # given