[Frontend] Support scores endpoint in run_batch (#12430)

Signed-off-by: Pooya Davoodi <pooya.davoodi@parasail.io>

tests/entrypoints/openai/test_run_batch.py

@@ -1,3 +1,4 @@
+import json
 import subprocess
 import sys
 import tempfile
@@ -21,6 +22,9 @@ INPUT_EMBEDDING_BATCH = """{"custom_id": "request-1", "method": "POST", "url": "
 {"custom_id": "request-3", "method": "POST", "url": "/v1/embeddings", "body": {"model": "intfloat/e5-mistral-7b-instruct", "input": "Hello world!"}}
 {"custom_id": "request-4", "method": "POST", "url": "/v1/embeddings", "body": {"model": "NonExistModel", "input": "Hello world!"}}"""
 
+INPUT_SCORE_BATCH = """{"custom_id": "request-1", "method": "POST", "url": "/v1/score", "body": {"model": "BAAI/bge-reranker-v2-m3", "text_1": "What is the capital of France?", "text_2": ["The capital of Brazil is Brasilia.", "The capital of France is Paris."]}}
+{"custom_id": "request-2", "method": "POST", "url": "/v1/score", "body": {"model": "BAAI/bge-reranker-v2-m3", "text_1": "What is the capital of France?", "text_2": ["The capital of Brazil is Brasilia.", "The capital of France is Paris."]}}"""
+
 
 def test_empty_file():
     with tempfile.NamedTemporaryFile(
@@ -102,3 +106,36 @@ def test_embeddings():
             # Ensure that the output format conforms to the openai api.
             # Validation should throw if the schema is wrong.
             BatchRequestOutput.model_validate_json(line)
+
+
+def test_score():
+    with tempfile.NamedTemporaryFile(
+            "w") as input_file, tempfile.NamedTemporaryFile(
+                "r") as output_file:
+        input_file.write(INPUT_SCORE_BATCH)
+        input_file.flush()
+        proc = subprocess.Popen([
+            sys.executable,
+            "-m",
+            "vllm.entrypoints.openai.run_batch",
+            "-i",
+            input_file.name,
+            "-o",
+            output_file.name,
+            "--model",
+            "BAAI/bge-reranker-v2-m3",
+        ], )
+        proc.communicate()
+        proc.wait()
+        assert proc.returncode == 0, f"{proc=}"
+
+        contents = output_file.read()
+        for line in contents.strip().split("\n"):
+            # Ensure that the output format conforms to the openai api.
+            # Validation should throw if the schema is wrong.
+            BatchRequestOutput.model_validate_json(line)
+
+            # Ensure that there is no error in the response.
+            line_dict = json.loads(line)
+            assert isinstance(line_dict, dict)
+            assert line_dict["error"] is None