fix: exceptions raised in apply from a remote_function now surfac…

…e in the client (#387)

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- [ ] Ensure the tests and linter pass
- [ ] Code coverage does not decrease (if any source code was changed)
- [ ] Appropriate docs were updated (if necessary)

Fixes internal issue 309699263 🦕

bigframes/functions/remote_function.py

@@ -21,7 +21,6 @@
 import random
 import shutil
 import string
-import subprocess
 import sys
 import tempfile
 import textwrap
@@ -87,19 +86,6 @@ def _get_hash(def_, package_requirements=None):
     return hashlib.md5(def_repr).hexdigest()
 
 
-def _run_system_command(command):
-    program = subprocess.Popen(
-        [command], stdout=subprocess.PIPE, stderr=subprocess.PIPE, shell=True
-    )
-    stdout, stderr = program.communicate()
-    exit_code = program.wait()
-    if exit_code:
-        raise RuntimeError(
-            f"Command: {command}\nOutput: {stdout.decode()}\nError: {stderr.decode()}"
-            f"{constants.FEEDBACK_LINK}"
-        )
-
-
 def routine_ref_to_string_for_query(routine_ref: bigquery.RoutineReference) -> str:
     return f"`{routine_ref.project}.{routine_ref.dataset_id}`.{routine_ref.routine_id}"
 
@@ -281,6 +267,8 @@ def generate_cloud_function_main_code(self, def_, dir):
         code_template = textwrap.dedent(
             """\
         import cloudpickle
+        import functions_framework
+        from flask import jsonify
         import json
 
         # original udf code is in {udf_code_file}
@@ -289,14 +277,17 @@ def generate_cloud_function_main_code(self, def_, dir):
           udf = cloudpickle.load(f)
 
         def {handler_func_name}(request):
-          request_json = request.get_json(silent=True)
-          calls = request_json["calls"]
-          replies = []
-          for call in calls:
-            reply = udf(*call)
-            replies.append(reply)
-          return_json = json.dumps({{"replies" : replies}})
-          return return_json
+          try:
+            request_json = request.get_json(silent=True)
+            calls = request_json["calls"]
+            replies = []
+            for call in calls:
+              reply = udf(*call)
+              replies.append(reply)
+            return_json = json.dumps({{"replies" : replies}})
+            return return_json
+          except Exception as e:
+            return jsonify( {{ "errorMessage": str(e) }} ), 400
         """
         )
 

tests/system/large/test_remote_function.py

@@ -21,7 +21,7 @@
 import tempfile
 import textwrap
 
-from google.api_core.exceptions import NotFound, ResourceExhausted
+from google.api_core.exceptions import BadRequest, NotFound, ResourceExhausted
 from google.cloud import bigquery, functions_v2
 import pandas
 import pytest
@@ -1214,6 +1214,28 @@ def square(x):
         )
 
 
+@pytest.mark.flaky(retries=2, delay=120)
+def test_remote_function_runtime_error(session, scalars_dfs, dataset_id):
+    try:
+
+        @session.remote_function([int], int, dataset=dataset_id)
+        def square(x):
+            return x * x
+
+        scalars_df, _ = scalars_dfs
+
+        with pytest.raises(
+            BadRequest, match="400.*errorMessage.*unsupported operand type"
+        ):
+            # int64_col has nulls which should cause error in square
+            scalars_df["int64_col"].apply(square).to_pandas()
+    finally:
+        # clean up the gcp assets created for the remote function
+        cleanup_remote_function_assets(
+            session.bqclient, session.cloudfunctionsclient, square
+        )
+
+
 @pytest.mark.flaky(retries=2, delay=120)
 def test_remote_function_anonymous_dataset(session, scalars_dfs):
     try: