Fix examples to reflect auto start topology(#5)

Rantfile

@@ -573,6 +573,12 @@ gen DirectedRule, topology_examples_objects_dir => [ topology_examples_source_di
   sys "gcc -I#{ Trema.include } -I#{ Trema.openflow } #{ var :CFLAGS } -c -o #{ t.name } #{ t.source }"
 end
 
+enable_discovery_objects = [
+  "enable_discovery.o",
+].collect do | each |
+  File.join topology_examples_objects_dir, each
+end
+
 show_topology_objects = [
   "show_topology.o",
 ].collect do | each |
@@ -586,6 +592,7 @@ show_switch_status_objects = [
 end
 
 topology_examples_binaries = {
+  "enable_discovery" => enable_discovery_objects,
   "show_topology" => show_topology_objects,
   "show_switch_status" => show_switch_status_objects,
 }

features/examples/topology.show_topology.feature

@@ -1,13 +1,26 @@
-Feature: show topology
-
-  As a Trema user
-  I want to control multiple openflow switches using topology application
-  So that I can show topology
+Feature: show_topology example.
+
+  show_topology is a simple usage example of topology C API.
+
+  show_topology command will query for all the link information that 
+  the topology daemon hold and print them in trema network DSL style.
+
+  Topology daemon's link discovery feature must be enabled prior to running 
+  show_topology command in order to obtain non-empty result.
+
+  Topology daemon's link discovery feature can be enabled 
+  by specifing "--always_run_discovery" option when starting topology daemon,
+  or by calling enable_topology_discovery() API from client application.  
+
 
+  Background: 
+    Given I cd to "../../src/examples/topology/"
 
   @slow_process
-  Scenario: Four openflow switches, four servers
-    Given a file named "topology.conf" with:
+  Scenario: [C API] Show discovered link topology. (Directly start topology daemon)
+    Given I compile "show_topology.c" into "show_topology"
+    Given I compile "enable_discovery.c" into "enable_discovery"
+    Given a file named "show_topology.conf" with:
       """
       vswitch("topology1") { datapath_id "0x1" }
       vswitch("topology2") { datapath_id "0x2" }
@@ -21,11 +34,10 @@ Feature: show topology
       link "topology2", "topology4"
       link "topology3", "topology4"
       """
-      And I run `trema run ../../objects/examples/dumper/dumper -c topology.conf -d`
-      And I run `trema run "../../objects/topology/topology --always_run_discovery -d"`
-      And wait until "topology" is up
-      And *** sleep 4 ***
-      And I run `trema run ../../objects/examples/topology/show_topology`
+    And I run `trema run ../repeater_hub/repeater-hub.rb -c show_topology.conf -d`
+    And I run `trema run "../../../objects/topology/topology -d --always_run_discovery"`
+    And *** sleep 4 ***
+    When I run `trema run ./show_topology`
     Then the output should contain:
       """
       vswitch {
@@ -75,4 +87,73 @@ Feature: show topology
       link "0x4", "0x1"
       """
 
-
+  @slow_process
+  Scenario: [C API] Show discovered link topology. (Enable link discovery by API)
+    Given I compile "show_topology.c" into "show_topology"
+    Given I compile "enable_discovery.c" into "enable_discovery"
+    Given a file named "show_topology.conf" with:
+      """
+      vswitch("topology1") { datapath_id "0x1" }
+      vswitch("topology2") { datapath_id "0x2" }
+      vswitch("topology3") { datapath_id "0x3" }
+      vswitch("topology4") { datapath_id "0x4" }
+      
+      link "topology1", "topology2"
+      link "topology1", "topology3"
+      link "topology1", "topology4"
+      link "topology2", "topology3"
+      link "topology2", "topology4"
+      link "topology3", "topology4"
+      """
+    And I run `trema run ../repeater_hub/repeater-hub.rb -c show_topology.conf -d`
+    And I run `trema run "./enable_discovery"`
+    And *** sleep 4 ***
+    When I run `trema run ./show_topology`
+    Then the output should contain:
+      """
+      vswitch {
+        datapath_id "0x2"
+      }
+      """
+    And the output should contain:
+      """
+      vswitch {
+        datapath_id "0x3"
+      }
+      """
+    And the output should contain:
+      """
+      vswitch {
+        datapath_id "0x1"
+      }
+      """
+    And the output should contain:
+      """
+      vswitch {
+        datapath_id "0x4"
+      }
+      """
+    And the output should contain:
+      """
+      link "0x2", "0x1"
+      """
+    And the output should contain:
+      """
+      link "0x3", "0x2"
+      """
+    And the output should contain:
+      """
+      link "0x3", "0x1"
+      """
+    And the output should contain:
+      """
+      link "0x4", "0x2"
+      """
+    And the output should contain:
+      """
+      link "0x4", "0x3"
+      """
+    And the output should contain:
+      """
+      link "0x4", "0x1"
+      """

src/examples/topology/.gitignore

@@ -0,0 +1,4 @@
+enable_discovery
+show_topology
+show_topology.conf
+

src/examples/topology/README.md

@@ -9,14 +9,17 @@ This directory includes sample application using libtopology.
 - `show_swith_status` is a command line application, which retrieves 
   switch and port information from Topology daemon and print them to stdout.
 
+- `enable_discovery` is a command line application, which enables
+  link discovery feature using the topology API.
+
 
         +----------+           +-----------+           +------+    +------------------+
         |  switch  |  *    1   | packet in |  1    *   |dumper|    |show_topology/    |
         |  daemon  | --------> |  filter   | --------> |      |    |show_switch_status|
         +----------+ packet in +-----------+ packet in +------+    +------------------+
           ^ 1    ^                       |                               * ^ 
-          |      |                       |                     libtopology | 
-          |      `-------.               |                                 |
+          |      |                       |                                 | 
+          |      `-------.               |                    topology API |
           v 1            |               |                               1 v 
         +----------+     |               |   packet in(LLDP)        +-----------+
         | openflow |     |               `------------------------->| topology  |
@@ -32,19 +35,31 @@ How to run
         $ cd $TREMA_HOME
         $ ./build.rb
 
-2. Start topology daemon
+2. Start network to discover
+
+        $ ./trema run ./objects/examples/dumper/dumper -c src/examples/topology/topology_fullmesh.conf &
+
+   # dumper is used in the above example, only because trema cannot run without 
+   # any controller specified.
+
+3. Enable link discovery feature
+   by adding "--always_run_discovery" option when starting topology
+
+        $ ./trema run ./objects/examples/topology/topology -d --always_run_discovery
+
+   Or by using API call.
 
-        $ ./trema run -c src/examples/topology/topology_fullmesh.conf &
+        $ ./trema run ./objects/examples/topology/enable_discovery
 
-3. Run show_topology/show_switch_status from trema run 
+4. Run show_topology/show_switch_status from trema run 
 
         $ ./trema run objects/examples/topology/show_topology
         $ ./trema run objects/examples/topology/show_switch_status
 
    Or invoke each commands directly
 
-        $ env TREMA_HOME=`pwd` objects/examples/topology/show_topology
-        $ env TREMA_HOME=`pwd` objects/examples/topology/show_switch_status
+        $ env TREMA_HOME=`pwd` src/examples/topology/show_topology
+        $ env TREMA_HOME=`pwd` src/examples/topology/show_switch_status
 
 
 License & Terms

src/examples/topology/enable_discovery.c

@@ -0,0 +1,77 @@
+/*
+ * Copyright (C) 2012 NEC Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+
+#include <assert.h>
+#include <getopt.h>
+#include <stdio.h>
+#include <unistd.h>
+#include "trema.h"
+
+
+void
+usage() {
+  topology_service_interface_usage( get_executable_name(), "Show switch status", NULL );
+}
+
+
+static void
+timed_out( void *user_data ) {
+  UNUSED( user_data );
+
+  error( "timed out." );
+
+  stop_trema();
+}
+
+
+static void
+result_response( void *user_data, const topology_response *res ) {
+  UNUSED( user_data );
+  if ( res->status != TD_RESPONSE_OK ) {
+    error( "Enable topology discovery failed" );
+  } else {
+    info( "Enabled topology discovery" );
+  }
+  stop_trema();
+}
+
+int
+main( int argc, char *argv[] ) {
+  init_trema( &argc, &argv );
+  init_topology_service_interface_options( &argc, &argv );
+  init_libtopology( get_topology_service_interface_name() );
+
+  enable_topology_discovery( result_response, NULL );
+
+  add_periodic_event_callback( 15, timed_out, NULL );
+
+  start_trema();
+
+  finalize_libtopology();
+  finalize_topology_service_interface_options();
+
+  return 0;
+}
+
+
+/*
+ * Local variables:
+ * c-basic-offset: 2
+ * indent-tabs-mode: nil
+ * End:
+ */

src/examples/topology/topology.conf

@@ -17,15 +17,3 @@ vhost ("host2") {
 link "0xe0", "host1"
 link "0xe0", "host2"
 
-
-run {
-  path "./objects/topology/topology"
-  options "--always_run_discovery"
-}
-
-run {
-  path "./objects/examples/dumper/dumper"
-}
-
-event :port_status => "topology", :packet_in => "filter", :state_notify => "topology"
-filter :lldp => "topology", :packet_in => "dumper"

src/examples/topology/topology_fullmesh.conf

@@ -48,15 +48,3 @@ link "0xe0", "0xe3"
 link "0xe1", "0xe2"
 link "0xe1", "0xe3"
 link "0xe2", "0xe3"
-
-run {
-  path "./objects/topology/topology"
-  options "--always_run_discovery"
-}
-
-run {
-  path "./objects/examples/dumper/dumper"
-}
-
-event :port_status => "topology", :packet_in => "filter", :state_notify => "topology"
-filter :lldp => "topology", :packet_in => "dumper"