Add password authentication to Redis ports (#2952)

* Implement Redis authentication

* Throw exception for legacy Ray

* Add test

* Formatting

* Fix bugs in CLI

* Fix bugs in Raylet

* Move default password to constants.h

* Use pytest.fixture

* Fix bug

* Authenticate using formatted strings

* Add missing passwords

* Add test

* Improve authentication of async contexts

* Disable Redis authentication for credis

* Update test for credis

* Fix rebase artifacts

* Fix formatting

* Add workaround for issue #3045

* Increase timeout for test

* Improve C++ readability

* Fixes for CLI

* Add security docs

* Address comments

* Address comments

* Adress comments

* Use ray.get

* Fix lint

python/ray/log_monitor.py

@@ -35,11 +35,15 @@ class LogMonitor(object):
             handle for that file.
     """
 
-    def __init__(self, redis_ip_address, redis_port, node_ip_address):
+    def __init__(self,
+                 redis_ip_address,
+                 redis_port,
+                 node_ip_address,
+                 redis_password=None):
         """Initialize the log monitor object."""
         self.node_ip_address = node_ip_address
         self.redis_client = redis.StrictRedis(
-            host=redis_ip_address, port=redis_port)
+            host=redis_ip_address, port=redis_port, password=redis_password)
         self.log_files = {}
         self.log_file_handles = {}
         self.files_to_ignore = set()
@@ -130,6 +134,12 @@ if __name__ == "__main__":
         required=True,
         type=str,
         help="The IP address of the node this process is on.")
+    parser.add_argument(
+        "--redis-password",
+        required=False,
+        type=str,
+        default=None,
+        help="the password to use for Redis")
     parser.add_argument(
         "--logging-level",
         required=False,
@@ -151,6 +161,9 @@ if __name__ == "__main__":
     redis_ip_address = get_ip_address(args.redis_address)
     redis_port = get_port(args.redis_address)
 
-    log_monitor = LogMonitor(redis_ip_address, redis_port,
-                             args.node_ip_address)
+    log_monitor = LogMonitor(
+        redis_ip_address,
+        redis_port,
+        args.node_ip_address,
+        redis_password=args.redis_password)
     log_monitor.run()