PAPI: Expose API enums to tests / applications

e.g:
from vpp_papi import VppEnum

VppEnum.vl_api_address_family_t.ADDRESS_IP4

Change-Id: I10c22d57234a1a06e98a889cf80b19085b468ed3
Signed-off-by: Ole Troan <ot@cisco.com>

2 files changed, 43 insertions, 16 deletions

diff --git a/src/vpp-api/python/vpp_papi/vpp_papi.py b/src/vpp-api/python/vpp_papi/vpp_papi.py
index e1a7059f317..5e98f92cecd 100644
--- a/src/vpp-api/python/vpp_papi/vpp_papi.py
+++ b/src/vpp-api/python/vpp_papi/vpp_papi.py
@@ -27,7 +27,7 @@ import fnmatch
 import weakref
 import atexit
 from . vpp_serializer import VPPType, VPPEnumType, VPPUnionType, BaseTypes
-from . vpp_serializer import VPPMessage
+from . vpp_serializer import VPPMessage, vpp_get_type
 
 if sys.version[0] == '2':
     import Queue as queue
@@ -35,6 +35,19 @@ else:
     import queue as queue
 
 
+class VppEnumType(type):
+    def __getattr__(cls, name):
+        t = vpp_get_type(name)
+        return t.enum
+
+
+# Python3
+# class VppEnum(metaclass=VppEnumType):
+#    pass
+class VppEnum:
+    __metaclass__ = VppEnumType
+
+
 def vpp_atexit(vpp_weakref):
     """Clean up VPP connection on shutdown."""
     vpp_instance = vpp_weakref()
@@ -94,21 +107,22 @@ class VPP():
             unresolved = {}
             for k, v in types.items():
                 t = v['data']
-                if v['type'] == 'enum':
-                    try:
-                        VPPEnumType(t[0], t[1:])
-                    except ValueError:
-                        unresolved[k] = v
-                elif v['type'] == 'union':
-                    try:
-                        VPPUnionType(t[0], t[1:])
-                    except ValueError:
-                        unresolved[k] = v
-                elif v['type'] == 'type':
-                    try:
-                        VPPType(t[0], t[1:])
-                    except ValueError:
-                        unresolved[k] = v
+                if not vpp_get_type(t[0]):
+                    if v['type'] == 'enum':
+                        try:
+                            VPPEnumType(t[0], t[1:])
+                        except ValueError:
+                            unresolved[k] = v
+                    elif v['type'] == 'union':
+                        try:
+                            VPPUnionType(t[0], t[1:])
+                        except ValueError:
+                            unresolved[k] = v
+                    elif v['type'] == 'type':
+                        try:
+                            VPPType(t[0], t[1:])
+                        except ValueError:
+                            unresolved[k] = v
             if len(unresolved) == 0:
                 break
             if i > 3:
@@ -200,6 +214,9 @@ class VPP():
                 return self.context
     get_context = ContextId()
 
+    def get_type(self, name):
+        return vpp_get_type(name)
+
     @classmethod
     def find_api_dir(cls):
         """Attempt to find the best directory in which API definition
diff --git a/src/vpp-api/python/vpp_papi/vpp_serializer.py b/src/vpp-api/python/vpp_papi/vpp_serializer.py
index cac6dd61791..240912d96ba 100644
--- a/src/vpp-api/python/vpp_papi/vpp_serializer.py
+++ b/src/vpp-api/python/vpp_papi/vpp_serializer.py
@@ -62,6 +62,13 @@ types['f64'] = BaseTypes('f64')
 types['bool'] = BaseTypes('bool')
 
 
+def vpp_get_type(name):
+    try:
+        return types[name]
+    except KeyError:
+        return None
+
+
 class FixedList_u8():
     def __init__(self, name, field_type, num):
         self.name = name
@@ -202,6 +209,9 @@ class VPPEnumType():
     def __getattr__(self, name):
         return self.enum[name]
 
+    def __nonzero__(self):
+        return True
+
     def pack(self, data, kwargs=None):
         return types['u32'].pack(data, kwargs)