Add MPLS config option and interface.is_mpls()

Also add tests and documentation

docs/config-guide.md

@@ -306,6 +306,8 @@ exist as a PHY in VPP (ie. `HundredGigabitEthernet12/0/0`) or as a specified `Bo
     If it is not specified, the link is considered admin 'up'.
 *   ***device-type***: An optional interface type in VPP. Currently the only supported vlaue is
     `dpdk`, and it is used to generate correct mock interfaces if the `--novpp` flag is used.
+*   ***mpls***: An optional boolean that configures MPLS on the interface or sub-interface. The
+    default value is `false`, if the field is not specified, which means MPLS will not be enabled.
 
 Further, top-level interfaces, that is to say those that do not have an encapsulation, are permitted
 to have any number of sub-interfaces specified by `subid`, an integer between [0,2G), which further
@@ -330,6 +332,7 @@ interfaces:
     lcp: "ice0"
     mtu: 9000
     addresses: [ 192.0.2.1/30, 2001:db8:1::1/64 ]
+    mpls: true
     sub-interfaces:
       1234:
         mtu: 9000
@@ -338,6 +341,7 @@ interfaces:
       1235:
         mtu: 1500
         lcp: "ice0.qinq"
+        mpls: true
         addresses: [ 192.0.2.9/30, 2001:db8:3::1/64 ]
         encapsulation:
           dot1q: 1234

vppcfg/config/interface.py

@@ -701,3 +701,14 @@ def validate_interfaces(yaml):
                         result = False
 
     return result, msgs
+
+
+def is_mpls(yaml, ifname):
+    """Returns True if the interface exists and has mpls enabled. Returns false otherwise."""
+    ifname, iface = get_by_name(yaml, ifname)
+    try:
+        if iface["mpls"] == True:
+            return True
+    except:
+        pass
+    return False

vppcfg/config/test_interface.py

@@ -277,3 +277,10 @@ class TestInterfaceMethods(unittest.TestCase):
         self.assertFalse(
             interface.get_admin_state(self.cfg, "GigabitEthernet1/0/0.102")
         )
+
+    def test_is_mpls(self):
+        self.assertTrue(interface.is_mpls(self.cfg, "GigabitEthernet1/0/1"))
+        self.assertTrue(interface.is_mpls(self.cfg, "GigabitEthernet1/0/1.101"))
+        self.assertFalse(interface.is_mpls(self.cfg, "GigabitEthernet1/0/0"))
+        self.assertFalse(interface.is_mpls(self.cfg, "GigabitEthernet1/0/0.100"))
+        self.assertFalse(interface.is_mpls(self.cfg, "notexist"))

vppcfg/example.yaml

@@ -20,7 +20,8 @@ interfaces:
     lcp: "ice12-0-0"
     mac: f2:01:00:12:00:00
     mtu: 9000
-    addresses: [ 192.0.2.17/30, 2001:DB8:3::1/64 ]
+    addresses: [ 192.0.2.17/30, 2001:db8:3::1/64 ]
+    mpls: true
     sub-interfaces:
       1234:
         mtu: 1200

vppcfg/schema.yaml

@@ -52,6 +52,7 @@ interface:
   sub-interfaces: map(include('sub-interface'),key=int(min=1,max=4294967295),required=False)
   l2xc: str(required=False)
   state: enum('up', 'down', required=False)
+  mpls: bool(required=False)
   device-type: enum('dpdk', required=False)
 ---
 sub-interface:
@@ -62,6 +63,7 @@ sub-interface:
   encapsulation: include('encapsulation',required=False)
   l2xc: str(required=False)
   state: enum('up', 'down', required=False)
+  mpls: bool(required=False)
 ---
 encapsulation:
   dot1q: int(min=1,max=4095,required=False)

vppcfg/unittest/test_interface.yaml

@@ -23,6 +23,7 @@ interfaces:
     mtu: 9216
     lcp: "e1"
     addresses: [ "192.0.2.1/30", "2001:db8:1::1/64" ]
+    mpls: true
     sub-interfaces:
       100:
         lcp: "foo"
@@ -33,6 +34,7 @@ interfaces:
           exact-match: True
         lcp: "e1.100"
         addresses: [ "10.0.2.1/30" ]
+        mpls: true
       102:
         encapsulation:
           dot1ad: 100