[core][executor] Support pushing the control port via env var

OCTRL-81 #close

Author: teo

core/scheduler.go

@@ -481,8 +481,10 @@ func resourceOffers(state *internalState, fidStore store.Singleton) events.Handl
 					remainingResources.Subtract(builder.Resource)
 
 					// Append control port to arguments
+					// For the control port parameter and/or environment variable, see occ/OccGlobals.h
 					cmd.Arguments = append(cmd.Arguments, "--control-port", strconv.FormatUint(controlPort, 10))
 					cmd.ControlPort = controlPort
+					cmd.Env = append(cmd.Env, fmt.Sprintf("%s=%d", "OCC_CONTROL_PORT", controlPort))
 
 					runCommand := *cmd
 

executor/executor.go

@@ -432,7 +432,7 @@ func launch(state *internalState, task mesos.TaskInfo) {
 	} else {
 		taskCmd = exec.Command(*commandInfo.Value, commandInfo.Arguments...)
 	}
-	taskCmd.Env = append(os.Environ())
+	taskCmd.Env = append(os.Environ(), commandInfo.Env...)
 
 	var errStdout, errStderr error
 	stdoutIn, _ := taskCmd.StdoutPipe()