Set seed value using CLI (gazebosim#1618)

* expose --seed to CLI
Signed-off-by: Aditya <[email protected]>

Author: adityapande-1995

src/cmd/cmdsim.rb.in

@@ -104,6 +104,9 @@ COMMANDS = { 'sim' =>
   "  --log-compress               When recording, compress final log files.        \n"\
   "                               Only valid if recording is enabled.              \n"\
   "\n"\
+  "  --seed [arg]                 Pass a custom seed value to the random           \n"\
+  "                               number generator.                                \n"\
+  "\n"\
   "  --playback [arg]             Use logging system to play back states.          \n"\
   "                               Argument is path to recorded states.             \n"\
   "\n"\
@@ -224,7 +227,8 @@ class Cmd
       'render_engine_gui' => '',
       'render_engine_server' => '',
       'wait_gui' => 1,
-      'headless-rendering' => 0
+      'headless-rendering' => 0,
+      'seed' => 0
     }
 
     usage = COMMANDS[args[0]]
@@ -317,6 +321,9 @@ class Cmd
       opts.on('--version') do
         options['version'] = '1'
       end
+      opts.on('--seed [arg]', Integer) do |i|
+        options['seed'] = i
+      end
 
     end # opt_parser do
 
@@ -455,7 +462,7 @@ Please use [GZ_SIM_RESOURCE_PATH] instead."
                                const char *, int, int, const char *,
                                int, int, int, const char *, const char *,
                                const char *, const char *, const char *,
-                               const char *, int, int)'
+                               const char *, int, int, int)'
 
       # Import the runGui function
       Importer.extern 'int runGui(const char *, const char *, int, const char *)'
@@ -491,7 +498,8 @@ See https://github.com/gazebosim/gz-sim/issues/44 for more info."
             options['render_engine_server'], options['render_engine_gui'],
             options['file'], options['record-topics'].join(':'),
             options['wait_gui'],
-            options['headless-rendering'])
+            options['headless-rendering'], options['seed'])
+
         end
 
         guiPid = Process.fork do
@@ -528,8 +536,10 @@ See https://github.com/gazebosim/gz-sim/issues/44 for more info."
             options['playback'], options['physics_engine'],
             options['render_engine_server'], options['render_engine_gui'],
             options['file'], options['record-topics'].join(':'),
-            options['wait_gui'], options['headless-rendering'])
-            # Otherwise run the gui
+            options['wait_gui'],
+            options['headless-rendering'], options['seed'])
+      # Otherwise run the gui
+
       else options['gui']
         ENV['RMT_PORT'] = '1501'
         Importer.runGui(options['gui_config'], options['file'],

src/gz.cc

@@ -136,7 +136,7 @@ extern "C" int runServer(const char *_sdfString,
     const char *_playback, const char *_physicsEngine,
     const char *_renderEngineServer, const char *_renderEngineGui,
     const char *_file, const char *_recordTopics, int _waitGui,
-    int _headless)
+    int _headless, int _seed)
 {
   std::string startingWorldPath{""};
   gz::sim::ServerConfig serverConfig;
@@ -396,6 +396,12 @@ extern "C" int runServer(const char *_sdfString,
     serverConfig.SetRenderEngineGui(_renderEngineGui);
   }
 
+  if (_seed != 0)
+  {
+    serverConfig.SetSeed(_seed);
+    gzmsg << "Setting seed value: " << _seed << "\n";
+  }
+
   // Create the Gazebo server
   gz::sim::Server server(serverConfig);
 

src/gz.hh

@@ -57,6 +57,7 @@ extern "C" const char *worldInstallDir();
 /// it receives a world path from GUI.
 /// null to record the default topics.
 /// \param[in] _headless True if server rendering should run headless
+/// \param[in] _seed --seed value to be used for random number generator.
 /// \return 0 if successful, 1 if not.
 extern "C" int runServer(const char *_sdfString,
     int _iterations, int _run, float _hz, int _levels,
@@ -65,7 +66,7 @@ extern "C" int runServer(const char *_sdfString,
     int _logCompress, const char *_playback,
     const char *_physicsEngine, const char *_renderEngineServer,
     const char *_renderEngineGui, const char *_file,
-    const char *_recordTopics, int _waitGui, int _headless);
+    const char *_recordTopics, int _waitGui, int _headless, int _seed);
 
 /// \brief External hook to run simulation GUI.
 /// \param[in] _guiConfig Path to Gazebo GUI configuration file.

src/gz_TEST.cc

@@ -109,6 +109,17 @@ TEST(CmdLine, GZ_UTILS_TEST_DISABLED_ON_WIN32(CachedFuelWorld))
       << output;
 }
 
+/////////////////////////////////////////////////
+TEST(CmdLine, GZ_UTILS_TEST_DISABLED_ON_WIN32(RandomSeedValue))
+{
+  std::string cmd = kGzCommand + " -r -v 4 --seed 5 --iterations 5";
+  std::cout << "Running command [" << cmd << "]" << std::endl;
+
+  std::string output = customExecStr(cmd);
+  EXPECT_NE(output.find("Setting seed value"), std::string::npos)
+      << output;
+}
+
 /////////////////////////////////////////////////
 TEST(CmdLine, GZ_UTILS_TEST_DISABLED_ON_WIN32(SimServer))
 {