utils: show error message when priority is missing (#452)

* p4runtime_lib/helper: use more appropriate variable names

Suggested-by: Antonin Bas <abas@vmware.com>
Signed-off-by: Radostin Stoyanov <rstoyanov@fedoraproject.org>

* utils: show error message when priority is missing

A 'priority' field is required to order entries when the
table's match key includes an optional, ternary or range match.

Suggested-by: Andy Fingerhut <andy_fingerhut@alum.wustl.edu>
Signed-off-by: Radostin Stoyanov <rstoyanov@fedoraproject.org>

utils/p4runtime_lib/helper.py

@@ -101,17 +101,17 @@ class P4InfoHelper(object):
             exact = p4runtime_match.exact
             exact.value = encode(value, bitwidth)
         elif match_type == p4info_pb2.MatchField.LPM:
-            lpm = p4runtime_match.lpm
+            lpm_entry = p4runtime_match.lpm
-            lpm.value = encode(value[0], bitwidth)
+            lpm_entry.value = encode(value[0], bitwidth)
-            lpm.prefix_len = value[1]
+            lpm_entry.prefix_len = value[1]
         elif match_type == p4info_pb2.MatchField.TERNARY:
-            lpm = p4runtime_match.ternary
+            ternary_entry = p4runtime_match.ternary
-            lpm.value = encode(value[0], bitwidth)
+            ternary_entry.value = encode(value[0], bitwidth)
-            lpm.mask = encode(value[1], bitwidth)
+            ternary_entry.mask = encode(value[1], bitwidth)
         elif match_type == p4info_pb2.MatchField.RANGE:
-            lpm = p4runtime_match.range
+            range_entry = p4runtime_match.range
-            lpm.low = encode(value[0], bitwidth)
+            range_entry.low = encode(value[0], bitwidth)
-            lpm.high = encode(value[1], bitwidth)
+            range_entry.high = encode(value[1], bitwidth)
         else:
             raise Exception("Unsupported match type with type %r" % match_type)
         return p4runtime_match

utils/p4runtime_lib/simple_controller.py

@@ -22,6 +22,8 @@ import sys
 from . import bmv2
 from . import helper
 
+from p4.config.v1 import p4info_pb2
+
 
 def error(msg):
     print(' - ERROR! ' + msg, file=sys.stderr)
@@ -88,7 +90,7 @@ def check_switch_conf(sw_conf, workdir):
             raise ConfException("file does not exist %s" % real_path)
 
 
-def program_switch(addr, device_id, sw_conf_file, workdir, proto_dump_fpath):
+def program_switch(addr, device_id, sw_conf_file, workdir, proto_dump_fpath, runtime_json):
     sw_conf = json_load_byteified(sw_conf_file)
     try:
         check_switch_conf(sw_conf=sw_conf, workdir=workdir)
@@ -126,6 +128,7 @@ def program_switch(addr, device_id, sw_conf_file, workdir, proto_dump_fpath):
             info("Inserting %d table entries..." % len(table_entries))
             for entry in table_entries:
                 info(tableEntryToString(entry))
+                validateTableEntry(entry, p4info_helper, runtime_json)
                 insertTableEntry(sw, entry, p4info_helper)
 
         if 'multicast_group_entries' in sw_conf:
@@ -146,6 +149,26 @@ def program_switch(addr, device_id, sw_conf_file, workdir, proto_dump_fpath):
         sw.shutdown()
 
 
+def validateTableEntry(flow, p4info_helper, runtime_json):
+    table_name = flow['table']
+    match_fields = flow.get('match')  # None if not found
+    priority = flow.get('priority')  # None if not found
+    match_types_with_priority = [
+        p4info_pb2.MatchField.TERNARY,
+        p4info_pb2.MatchField.RANGE
+    ]
+    if match_fields is not None and (priority is None or priority == 0):
+        for match_field_name, _ in match_fields.items():
+            p4info_match = p4info_helper.get_match_field(
+                table_name, match_field_name)
+            match_type = p4info_match.match_type
+            if match_type in match_types_with_priority:
+                raise AssertionError(
+                    "non-zero 'priority' field is required for all entries for table {} in {}"
+                    .format(table_name, runtime_json)
+                )
+
+
 def insertTableEntry(sw, flow, p4info_helper):
     table_name = flow['table']
     match_fields = flow.get('match') # None if not found

utils/run_exercise.py

@@ -273,7 +273,9 @@ class ExerciseRunner:
                 device_id=device_id,
                 sw_conf_file=sw_conf_file,
                 workdir=os.getcwd(),
-                proto_dump_fpath=outfile)
+                proto_dump_fpath=outfile,
+                runtime_json=runtime_json
+            )
 
     def program_switch_cli(self, sw_name, sw_dict):
         """ This method will start up the CLI and use the contents of the