stats: counters data model

This adds a new data model for counters.
Specifying the errors severity and unit.
A later patch will update vpp_get_stats to take advantage of this.
Only the map plugin is updates as an example.

New .api language:
A new "counters" keyword to define counter sets.

counters map {
  none {
    severity info;
    type counter64;
    units "packets";
    description "valid MAP packets";
  };
  bad_protocol {
    severity error;
    type counter64;
    units "packets";
    description "bad protocol";
  };
};

Each counter has 4 keywords. severity, which is one of error, info or warn.
A type, which is one of counter64 or gauge64.
units, which is a text field using units from YANG.

paths {
  "/err/ip4-map" "map";
  "/err/ip6-map" "map";
  "/err/ip4-t-map" "map";
  "/err/ip6-t-map" "map";
};

A new paths keyword that maps the counter-set to a path in the stats segment KV store.

Updated VPP CLI to include severity so user can see error counter severity.
DBGvpp# show errors
   Count               Node                    Reason        Severity
        13        ethernet-input              no error         error

Type: feature
Signed-off-by: Ole Troan <ot@cisco.com>
Change-Id: Ib2177543f49d4c3aef4d7fa72476cff2068f7771
Signed-off-by: Ole Troan <ot@cisco.com>

1 files changed, 3 insertions, 21 deletions

diff --git a/src/plugins/cdp/test/test_cdp.py b/src/plugins/cdp/test/test_cdp.py
index 1bc67c45c3e..46751e81d86 100644
--- a/src/plugins/cdp/test/test_cdp.py
+++ b/src/plugins/cdp/test/test_cdp.py
@@ -108,18 +108,9 @@ class TestCDP(VppTestCase):
         self.logger.info(self.vapi.cdp_enable_disable(enable_disable=1))
         self.send_packet(self.create_bad_packet(l, v))
 
-        errors = list(self.show_errors())
-        self.assertTrue(errors)
-
-        expected_errors = False
-        for count, node, reason in errors:
-            if (node == u'cdp-input' and
-                    reason == u'cdp packets with bad TLVs' and
-                    int(count) >= 1):
-
-                expected_errors = True
-                break
-        self.assertTrue(expected_errors, "CDP didn't drop bad packet")
+        err = self.statistics.get_err_counter(
+            '/err/cdp-input/cdp packets with bad TLVs')
+        self.assertTrue(err >= 1, "CDP didn't drop bad packet")
 
     def send_packet(self, packet):
         self.logger.debug(ppp("Sending packet:", packet))
@@ -162,12 +153,3 @@ class TestCDP(VppTestCase):
                 pass
             else:
                 yield port, system
-
-    def show_errors(self):
-        for pack in self.process_cli("show errors", self.err_ptr):
-            try:
-                count, node, reason = pack
-            except ValueError:
-                pass
-            else:
-                yield count, node, reason