prompt: We are currently solving the following issue within our repository. Here is the issue text:
  --- BEGIN ISSUE ---
  Hide TensorBoard service REST call logs
  Currently these logs appear on master pod's log which is not necessary at user level:
  ```
  I0624 15:50:54.834580 140272641951488 _internal.py:122] ::ffff:10.138.0.35 - - [24/Jun/2019 15:50:54] "GET /data/plugin/scalars/tags HTTP/1.1" 200 -
  W0624 15:50:55.150964 140556554397440 servicer.py:195] Task result for outdated version 30 dropped
  I0624 15:50:57.245738 140272633558784 _internal.py:122] ::ffff:10.36.1.1 - - [24/Jun/2019 15:50:57] "GET /data/environment HTTP/1.1" 200 -
  I0624 15:50:57.250612 140271752836864 _internal.py:122] ::ffff:10.138.0.35 - - [24/Jun/2019 15:50:57] "GET /data/experiments HTTP/1.1" 200 -
  I0624 15:50:57.252254 140272105903872 _internal.py:122] ::ffff:10.36.1.1 - - [24/Jun/2019 15:50:57] "GET /data/runs HTTP/1.1" 200 -
  I0624 15:50:57.255696 140272641951488 _internal.py:122] ::ffff:10.138.0.35 - - [24/Jun/2019 15:50:57] "GET /data/plugins_listing HTTP/1.1" 200 -
  I0624 15:50:57.430979 140272641951488 _internal.py:122] ::ffff:10.138.0.35 - - [24/Jun/2019 15:50:57] "GET /data/plugin/scalars/tags HTTP/1.1" 200 -
  ```
  
  --- END ISSUE ---
  
  Below are some code segments, each from a relevant file. One or more of these files may contain bugs.
  --- BEGIN FILES ---
  Path: `elasticdl/python/elasticdl/master/tensorboard_service.py`
  Content:
  ```
  1 import datetime
  2 import subprocess
  3 import time
  4 
  5 import tensorflow as tf
  6 
  7 import numpy as np
  8 
  9 
  10 class TensorboardService(object):
  11     """Tensorboard Service implementation"""
  12 
  13     def __init__(self, tensorboard_log_dir):
  14         """
  15         Arguments:
  16             tensorboard_log_dir: The log directory for Tensorboard.
  17         """
  18         _current_time = datetime.datetime.now().strftime("%Y%m%d-%H%M%S")
  19         self._tensorboard_log_dir = tensorboard_log_dir + _current_time
  20         self._initialize_summary_writer()
  21         self.tb_process = None
  22 
  23     def _initialize_summary_writer(self):
  24         self.summary_writer = tf.summary.create_file_writer(
  25             self._tensorboard_log_dir
  26         )
  27 
  28     def write_dict_to_summary(self, dictionary, version):
  29         with self.summary_writer.as_default():
  30             for k, v in dictionary.items():
  31                 if isinstance(v, np.ndarray) and len(v) == 1:
  32                     v = v[0]
  33                 tf.summary.scalar(k, v, step=version)
  34 
  35     def start(self):
  36         self.tb_process = subprocess.Popen(
  37             ["tensorboard --logdir " + self._tensorboard_log_dir], shell=True
  38         )
  39 
  40     def keep_running(self):
  41         while self.tb_process.poll() is None:
  42             time.sleep(10)
  43
  ```
  --- END FILES ---
  
  Please first localize the bug based on the issue statement, and then generate a patch according to the `git diff` format fenced by three backticks.
  
  Here is an example:
  
  ```diff
  diff --git a/examples/server_async.py b/examples/server_async.py
  --- a/examples/server_async.py
  +++ b/examples/server_async.py
  @@ -313,4 +313,4 @@
   
   
   if __name__ == "__main__":
  -    asyncio.run(run_async_server("."), debug=True)
  +    asyncio.run(run_async_server(), debug=True)
  diff --git a/examples/server_sync.py b/examples/server_sync.py
  --- a/examples/server_sync.py
  +++ b/examples/server_sync.py
  @@ -313,5 +313,5 @@
   
   
   if __name__ == "__main__":
  -    server = run_sync_server(".")
  +    server = run_sync_server()
       server.shutdown()
  
  ```
  
golden_diff: diff --git a/elasticdl/python/elasticdl/master/tensorboard_service.py b/elasticdl/python/elasticdl/master/tensorboard_service.py
  --- a/elasticdl/python/elasticdl/master/tensorboard_service.py
  +++ b/elasticdl/python/elasticdl/master/tensorboard_service.py
  @@ -34,7 +34,10 @@
   
       def start(self):
           self.tb_process = subprocess.Popen(
  -            ["tensorboard --logdir " + self._tensorboard_log_dir], shell=True
  +            ["tensorboard --logdir " + self._tensorboard_log_dir],
  +            shell=True,
  +            stdout=subprocess.DEVNULL,
  +            stderr=subprocess.STDOUT,
           )
   
       def keep_running(self):
  
verification_info: {"golden_diff": "diff --git a/elasticdl/python/elasticdl/master/tensorboard_service.py b/elasticdl/python/elasticdl/master/tensorboard_service.py\n--- a/elasticdl/python/elasticdl/master/tensorboard_service.py\n+++ b/elasticdl/python/elasticdl/master/tensorboard_service.py\n@@ -34,7 +34,10 @@\n \n     def start(self):\n         self.tb_process = subprocess.Popen(\n-            [\"tensorboard --logdir \" + self._tensorboard_log_dir], shell=True\n+            [\"tensorboard --logdir \" + self._tensorboard_log_dir],\n+            shell=True,\n+            stdout=subprocess.DEVNULL,\n+            stderr=subprocess.STDOUT,\n         )\n \n     def keep_running(self):\n", "issue": "Hide TensorBoard service REST call logs\nCurrently these logs appear on master pod's log which is not necessary at user level:\r\n```\r\nI0624 15:50:54.834580 140272641951488 _internal.py:122] ::ffff:10.138.0.35 - - [24/Jun/2019 15:50:54] \"GET /data/plugin/scalars/tags HTTP/1.1\" 200 -\r\nW0624 15:50:55.150964 140556554397440 servicer.py:195] Task result for outdated version 30 dropped\r\nI0624 15:50:57.245738 140272633558784 _internal.py:122] ::ffff:10.36.1.1 - - [24/Jun/2019 15:50:57] \"GET /data/environment HTTP/1.1\" 200 -\r\nI0624 15:50:57.250612 140271752836864 _internal.py:122] ::ffff:10.138.0.35 - - [24/Jun/2019 15:50:57] \"GET /data/experiments HTTP/1.1\" 200 -\r\nI0624 15:50:57.252254 140272105903872 _internal.py:122] ::ffff:10.36.1.1 - - [24/Jun/2019 15:50:57] \"GET /data/runs HTTP/1.1\" 200 -\r\nI0624 15:50:57.255696 140272641951488 _internal.py:122] ::ffff:10.138.0.35 - - [24/Jun/2019 15:50:57] \"GET /data/plugins_listing HTTP/1.1\" 200 -\r\nI0624 15:50:57.430979 140272641951488 _internal.py:122] ::ffff:10.138.0.35 - - [24/Jun/2019 15:50:57] \"GET /data/plugin/scalars/tags HTTP/1.1\" 200 -\r\n```\n", "before_files": [{"content": "import datetime\nimport subprocess\nimport time\n\nimport tensorflow as tf\n\nimport numpy as np\n\n\nclass TensorboardService(object):\n    \"\"\"Tensorboard Service implementation\"\"\"\n\n    def __init__(self, tensorboard_log_dir):\n        \"\"\"\n        Arguments:\n            tensorboard_log_dir: The log directory for Tensorboard.\n        \"\"\"\n        _current_time = datetime.datetime.now().strftime(\"%Y%m%d-%H%M%S\")\n        self._tensorboard_log_dir = tensorboard_log_dir + _current_time\n        self._initialize_summary_writer()\n        self.tb_process = None\n\n    def _initialize_summary_writer(self):\n        self.summary_writer = tf.summary.create_file_writer(\n            self._tensorboard_log_dir\n        )\n\n    def write_dict_to_summary(self, dictionary, version):\n        with self.summary_writer.as_default():\n            for k, v in dictionary.items():\n                if isinstance(v, np.ndarray) and len(v) == 1:\n                    v = v[0]\n                tf.summary.scalar(k, v, step=version)\n\n    def start(self):\n        self.tb_process = subprocess.Popen(\n            [\"tensorboard --logdir \" + self._tensorboard_log_dir], shell=True\n        )\n\n    def keep_running(self):\n        while self.tb_process.poll() is None:\n            time.sleep(10)\n", "path": "elasticdl/python/elasticdl/master/tensorboard_service.py"}], "after_files": [{"content": "import datetime\nimport subprocess\nimport time\n\nimport tensorflow as tf\n\nimport numpy as np\n\n\nclass TensorboardService(object):\n    \"\"\"Tensorboard Service implementation\"\"\"\n\n    def __init__(self, tensorboard_log_dir):\n        \"\"\"\n        Arguments:\n            tensorboard_log_dir: The log directory for Tensorboard.\n        \"\"\"\n        _current_time = datetime.datetime.now().strftime(\"%Y%m%d-%H%M%S\")\n        self._tensorboard_log_dir = tensorboard_log_dir + _current_time\n        self._initialize_summary_writer()\n        self.tb_process = None\n\n    def _initialize_summary_writer(self):\n        self.summary_writer = tf.summary.create_file_writer(\n            self._tensorboard_log_dir\n        )\n\n    def write_dict_to_summary(self, dictionary, version):\n        with self.summary_writer.as_default():\n            for k, v in dictionary.items():\n                if isinstance(v, np.ndarray) and len(v) == 1:\n                    v = v[0]\n                tf.summary.scalar(k, v, step=version)\n\n    def start(self):\n        self.tb_process = subprocess.Popen(\n            [\"tensorboard --logdir \" + self._tensorboard_log_dir],\n            shell=True,\n            stdout=subprocess.DEVNULL,\n            stderr=subprocess.STDOUT,\n        )\n\n    def keep_running(self):\n        while self.tb_process.poll() is None:\n            time.sleep(10)\n", "path": "elasticdl/python/elasticdl/master/tensorboard_service.py"}]}