[Core] Allow users to specify the classpath and import path (#10560)

* move job resource path to job config

* job resource path support list

* job resource path support for python

* fix job_resource_path support

* fix worker command

* fix job config

* use jar file instead of parent path

* fix job resource path

* add test to test.sh

* lint

* Update java/runtime/src/main/resources/ray.default.conf

Co-authored-by: Kai Yang <kfstorm@outlook.com>

* fix testGetFunctionFromLocalResource

* lint

* fix rebase

* add jars in resource path to classloader

* add job_resource_path to worker

* add ray stop

* rename job_resource_path to resource_path

* fix resource_path

* refine resource_path comments

* rename job resource path to code search path

* Add instruction about starting a cross-language cluster

* fix ClassLoaderTest.java

* add code-search-path to RunManager

* refine comments for code-search-path

* rename resourcePath to codeSearchPath

* Update doc

* fix

* rename resourcePath to codeSearchPath

* update doc

* filter out empty path

* fix comments

* fix comments

* fix tests

* revert pom

* lint

* fix doc

* update doc

* Apply suggestions from code review

* lint

Co-authored-by: Kai Yang <kfstorm@outlook.com>
Co-authored-by: Hao Chen <chenh1024@gmail.com>

python/ray/workers/default_worker.py

@@ -1,6 +1,8 @@
 import argparse
 import json
 import time
+import sys
+import os
 
 import ray
 import ray.actor
@@ -98,7 +100,13 @@ parser.add_argument(
     type=str,
     default="",
     help="The configuration of object spilling. Only used by I/O workers.")
-
+parser.add_argument(
+    "--code-search-path",
+    default=None,
+    type=str,
+    help="A list of directories or jar files separated by colon that specify "
+    "the search path for user code. This will be used as `CLASSPATH` in "
+    "Java and `PYTHONPATH` in Python.")
 if __name__ == "__main__":
     args = parser.parse_args()
 
@@ -135,6 +143,13 @@ if __name__ == "__main__":
     if raylet_ip_address is None:
         raylet_ip_address = args.node_ip_address
 
+    code_search_path = args.code_search_path
+    if code_search_path is not None:
+        for p in code_search_path.split(":"):
+            if os.path.isfile(p):
+                p = os.path.dirname(p)
+            sys.path.append(p)
+
     ray_params = RayParams(
         node_ip_address=args.node_ip_address,
         raylet_ip_address=raylet_ip_address,