Add option to run MMS in the foreground

Author: vdantu

docs/configuration.md

@@ -21,6 +21,8 @@ User can following parameters to start MMS, those parameters will override defau
 * **--model-store** This parameter will override `model_store` property in config.properties file.
 * **--models** This parameter will override `load_models' property in config.properties.
 * **--log-config** This parameter will override default log4j.properties.
+* **--foreground** This parameter will run the model server in foreground. If this option is
+                        disabled, the model server will run in the background.
 
 See [Running the Model Server](server.md) for detail.
 

mms/arg_parser.py

@@ -48,6 +48,10 @@ def mms_parser():
         parser.add_argument('--log-config',
                             dest='log_config',
                             help='Log4j configuration file for model server')
+        parser.add_argument('--foreground',
+                            help='Run the model server in foreground. If this option is disabled, the model server'
+                                 ' will run in the background.',
+                            action='store_true')
 
         return parser
 

mms/model_server.py

@@ -132,6 +132,8 @@ def start():
             pid = process.pid
             with open(pid_file, "w") as pf:
                 pf.write(str(pid))
+            if args.foreground:
+                process.wait()
         except OSError as e:
             if e.errno == 2:
                 print("java not found, please make sure JAVA_HOME is set properly.")