add path-info parsing to announce attributes #1147

etc/exabgp/api-attributes-path.conf

@@ -0,0 +1,26 @@
+process announce-routes {
+	run ./run/api-attributes-path.run;
+	encoder text;
+}
+
+neighbor 127.0.0.1 {
+	router-id 1.2.3.4;
+	local-address 127.0.0.1;
+	local-as 300;
+	peer-as 300;
+
+	family {
+		ipv4 unicast;
+		ipv6 unicast;
+	}
+
+	capability {
+		add-path send/receive;
+		route-refresh;
+	}
+
+	api {
+		processes [ announce-routes ];
+		neighbor-changes;
+	}
+}

etc/exabgp/run/api-attributes-path.run

@@ -0,0 +1,26 @@
+#!/usr/bin/env python3
+
+import os
+import sys
+import time
+
+messages = [
+	'neighbor 127.0.0.1 announce attributes path-information 1.2.3.4 next-hop 10.11.12.13 community [14:15] local-preference 16 nlri 16.17.18.19/32 20.21.22.23/32',
+	'neighbor 127.0.0.1 announce attributes path-information 4.3.2.1 next-hop 10.11.12.13 community [14:15] local-preference 16 nlri 16.17.18.19/32 20.21.22.23/32',
+]
+
+while messages:
+    message = messages.pop(0)
+    sys.stdout.write(message + '\n')
+    sys.stdout.flush()
+    time.sleep(0.3)
+
+try:
+    now = time.time()
+    while os.getppid() != 1 and time.time() < now + 5:
+        line = sys.stdin.readline().strip()
+        if not line or 'shutdown' in line:
+            break
+        time.sleep(1)
+except IOError:
+    pass

qa/ci/api-attributes-path.ci

@@ -0,0 +1 @@
+api-attributes-path.conf

qa/ci/api-attributes-path.msg

@@ -0,0 +1,4 @@
+1:raw:FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF:001702:00000000
+1:raw:FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF:001E:02:00000007900F0003000201
+1:raw:FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF:0045:02:0000001C400101004002004003040A0B0C0D40050400000010C00804000E000F010203042010111213010203042014151617
+1:raw:FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF:0045:02:0000001C400101004002004003040A0B0C0D40050400000010C00804000E000F040302012010111213040302012014151617

src/exabgp/application/decode.py

@@ -16,28 +16,19 @@
 from exabgp.logger import log
 
 
-conf_all = """\
+conf_template = """\
 neighbor 127.0.0.1 {
     router-id 10.0.0.2;
     local-address 127.0.0.1;
     local-as 65533;
     peer-as 65533;
 
     family {
-        all;
+        [families];
     }
-}
-"""
 
-conf_none = """\
-neighbor 127.0.0.1 {
-    router-id 10.0.0.2;
-    local-address 127.0.0.1;
-    local-as 65533;
-    peer-as 65533;
-
-    family {
-        [families];
+    capability {
+        [path-information]
     }
 }
 """
@@ -54,7 +45,8 @@ def setargs(sub):
     sub.add_argument('-d', '--debug', help='start the python debugger errors', action='store_true')
     sub.add_argument('-p', '--pdb', help='fire the debugger on fault', action='store_true')
     sub.add_argument('-c', '--configuration', help='configuration file(s)', type=str)
-    sub.add_argument('-f', '--family', help='family expected', type=str)
+    sub.add_argument('-f', '--family', help='family expected (format like "ipv4 unicast")', type=str)
+    sub.add_argument('-i', '--path-information', help='decode path-information', action='store_true')
     sub.add_argument('payload', help='the BGP payload in hexadecimal', type=str)
     # fmt:on
 
@@ -97,6 +89,8 @@ def cmdline(cmdarg):
     log.init(env)
     trace_interceptor(env.debug.pdb)
 
+    conf = conf_template.replace('[path-information]', 'add-path send/receive;' if cmdarg.path_information else '')
+
     sanitized = ''.join(cmdarg.payload).replace(':', '').replace(' ', '')
     if cmdarg.configuration:
         configuration = Configuration([getconf(cmdarg.configuration)])
@@ -109,11 +103,12 @@ def cmdline(cmdarg):
             sys.exit(1)
         families_pair = [families[n : n + 2] for n in range(0, len(families), 2)]
         families_text = ';'.join([f'{a} {s}' for a, s in families_pair])
-        conf = conf_none.replace('[families]', families_text)
+        conf = conf.replace('[families]', families_text)
         configuration = Configuration([conf], text=True)
 
     else:
-        configuration = Configuration([conf_all], text=True)
+        conf = conf.replace('[families]', 'all')
+        configuration = Configuration([conf], text=True)
 
     valid_nlri = Reactor(configuration).display(sanitized, cmdarg.nlri)
     if valid_nlri:

src/exabgp/configuration/static/__init__.py

@@ -29,6 +29,7 @@
 
 from exabgp.configuration.static.mpls import label
 from exabgp.configuration.static.mpls import route_distinguisher
+from exabgp.configuration.static.parser import path_information
 
 
 def _check_true(change, afi):
@@ -89,6 +90,10 @@ def route(tokeniser):
             nlri.rd = route_distinguisher(tokeniser)
             continue
 
+        if command == 'path-information':
+            nlri.path_info = path_information(tokeniser)
+            continue
+
         action = ParseStatic.action.get(command, '')
 
         if action == 'attribute-add':
@@ -126,6 +131,7 @@ def attributes(tokeniser):
 
     labels = None
     rd = None
+    path = None
 
     while True:
         command = tokeniser()
@@ -140,6 +146,10 @@ def attributes(tokeniser):
             labels = label(tokeniser)
             continue
 
+        if command == 'path-information':
+            path = path_information(tokeniser)
+            continue
+
         if command == 'rd' or command == 'route-distinguisher':
             rd = route_distinguisher(tokeniser)
             continue
@@ -160,6 +170,7 @@ def attributes(tokeniser):
             raise ValueError('unknown command "%s"' % command)
 
     changes = []
+
     while True:
         peeked_nlri = tokeniser.peek()
         if not peeked_nlri:
@@ -172,6 +183,8 @@ def attributes(tokeniser):
             new.nlri.labels = labels
         if rd:
             new.nlri.rd = rd
+        if path:
+            new.nlri.path_info = path
         new.nlri.nexthop = nlri.nexthop
         changes.append(new)