Parse raw_data on error only if the Content-Type is application/json.

opensearchpy/connection/base.py

@@ -314,12 +314,13 @@ def log_request_fail(
         if response is not None:
             logger.debug("< %s", response)
 
-    def _raise_error(self, status_code, raw_data):
+    def _raise_error(self, status_code, raw_data, content_type=""):
         """Locate appropriate exception and raise it."""
         error_message = raw_data
         additional_info = None
         try:
-            if raw_data:
+            content_type = content_type.split(";")[0].strip() or "application/json"
+            if raw_data and content_type == "application/json":
                 additional_info = json.loads(raw_data)
                 error_message = additional_info.get("error", error_message)
                 if isinstance(error_message, dict) and "type" in error_message:

opensearchpy/connection/base.pyi

@@ -112,6 +112,8 @@ class Connection(object):
         response: Optional[str] = ...,
         exception: Optional[Exception] = ...,
     ) -> None: ...
-    def _raise_error(self, status_code: int, raw_data: str) -> NoReturn: ...
+    def _raise_error(
+        self, status_code: int, raw_data: str, content_type: Optional[str]
+    ) -> NoReturn: ...
     def _get_default_user_agent(self) -> str: ...
     def _get_api_key_header_val(self, api_key: Any) -> str: ...

opensearchpy/connection/http_requests.py

@@ -207,7 +207,11 @@ def perform_request(
                 response.status_code,
                 raw_data,
             )
-            self._raise_error(response.status_code, raw_data)
+            self._raise_error(
+                response.status_code,
+                raw_data,
+                response.headers.get("Content-Type", ""),
+            )
 
         self.log_request_success(
             method,

opensearchpy/connection/http_urllib3.py

@@ -279,14 +279,21 @@ def perform_request(
             self.log_request_fail(
                 method, full_url, url, orig_body, duration, response.status, raw_data
             )
-            self._raise_error(response.status, raw_data)
+            self._raise_error(
+                response.status,
+                raw_data,
+                self.get_response_headers(response).get("content-type", ""),
+            )
 
         self.log_request_success(
             method, full_url, url, orig_body, response.status, raw_data, duration
         )
 
         return response.status, response.getheaders(), raw_data
 
+    def get_response_headers(self, response):
+        return {header.lower(): value for header, value in response.headers.items()}
+
     def close(self):
         """
         Explicitly closes connection

test_opensearchpy/test_connection.py

@@ -31,10 +31,12 @@
 import os
 import re
 import ssl
+import unittest
 import warnings
 from platform import python_version
 
 import pytest
+import six
 import urllib3
 from mock import Mock, patch
 from requests.auth import AuthBase
@@ -163,6 +165,19 @@ def test_raises_warnings_when_folded(self):
 
         self.assertEqual([str(w.message) for w in warn], ["warning", "folded"])
 
+    @unittest.skipIf(six.PY2, "not compatible with python2")
+    def test_raises_errors(self):
+        con = Connection()
+        with self.assertLogs("opensearch") as captured, self.assertRaises(
+            NotFoundError
+        ):
+            con._raise_error(404, "Not found")
+        self.assertEqual(len(captured.output), 1)
+
+        # NB: this should assertNoLogs() but that method is not available until python3.10
+        with self.assertRaises(NotFoundError):
+            con._raise_error(404, "Not found", "text/plain; charset=UTF-8")
+
     def test_ipv6_host_and_port(self):
         for kwargs, expected_host in [
             ({"host": "::1"}, "http://[::1]:9200"),