Removing surface_header_value validation (#277)

Completes b/453012979

We originally validated that the incoming surface header was either in
the form "mcp-<some version number" or "datagemma", to avoid public use
of this field that is supposed to only identify data commons surfaces
for mixer logs.

However, this makes it challenging to change the surface header or
introduce new surfaces, and doesn't allow release candidate versions of
the MCP server because the version number contains letters. I removed
this validation entirely and will instead validate that the surface is
an actual DC feature in my usage logs in mixer, where I can loosen
validation without releasing a new PyPi package.

(also updates version bump because of a previous change)

Author: lucyking140

CHANGELOG.md

@@ -2,7 +2,7 @@
 
 ## 2.1.2
 
-**Date** - 09/23/2025
+**Date** - 10/16/2025
 
 **Release Tag** - [py2.1.2](https://github.com/datacommonsorg/api-python/releases/tag/py2.1.2)
 

datacommons_client/__init__.py

@@ -1,4 +1,4 @@
-__version__ = "2.1.2rc1"
+__version__ = "2.1.2"
 """
 Data Commons Client Package
 

datacommons_client/endpoints/base.py

@@ -1,8 +1,6 @@
 import re
 from typing import Any, Dict, Optional
 
-from datacommons_client.utils.error_handling import InvalidSurfaceHeaderValueError
-from datacommons_client.utils.error_handling import VALID_SURFACE_HEADER_VALUES
 from datacommons_client.utils.request_handling import check_instance_is_valid
 from datacommons_client.utils.request_handling import post_request
 from datacommons_client.utils.request_handling import resolve_instance_url
@@ -52,15 +50,6 @@ def __init__(
       # Resolve from dc_instance
       self.base_url = resolve_instance_url(dc_instance)
 
-    # if this call originates from another DC product (MCP server, DataGemma, etc.), we indicate that to Mixer
-    # otherwise, the 'x-surface' header is 'clientlib-python'
-    if surface_header_value:
-      # use patterns to support tags like mcp-{VERSION}
-      if not any(
-          re.fullmatch(pattern, surface_header_value)
-          for pattern in VALID_SURFACE_HEADER_VALUES):
-        raise InvalidSurfaceHeaderValueError
-
     self.headers = self.build_headers(surface_header_value=surface_header_value,
                                       api_key=api_key)
 

datacommons_client/tests/endpoints/test_base.py

@@ -4,7 +4,6 @@
 
 from datacommons_client.endpoints.base import API
 from datacommons_client.endpoints.base import Endpoint
-from datacommons_client.utils.error_handling import InvalidSurfaceHeaderValueError
 
 
 @patch(
@@ -63,7 +62,7 @@ def test_api_initialization_with_dc_instance(mock_resolve_instance_url):
     return_value="https://custom-instance/api/v2",
 )
 def test_api_initialization_with_surface_header(mock_url):
-  """Tests API initialization with an invalid surface header raises an InvalidSurfaceHeaderValueError."""
+  """Tests API initialization with a surface header """
   api = API(dc_instance="custom-instance", surface_header_value="mcp-1.1.0")
   assert api.headers == {
       "Content-Type": "application/json",
@@ -77,16 +76,6 @@ def test_api_initialization_invalid_args():
     API(dc_instance="custom-instance", url="https://custom.api/v2")
 
 
-@patch(
-    "datacommons_client.endpoints.base.resolve_instance_url",
-    return_value="https://custom-instance/api/v2",
-)
-def test_api_initialization_invalid_surface(mock_url):
-  """Tests API initialization with an invalid surface header raises an InvalidSurfaceHeaderValueError."""
-  with pytest.raises(InvalidSurfaceHeaderValueError):
-    API(dc_instance="custom-instance", surface_header_value="not mcp")
-
-
 @patch(
     "datacommons_client.endpoints.base.resolve_instance_url",
     return_value="https://custom-instance/api/v2",

datacommons_client/utils/error_handling.py

@@ -87,14 +87,3 @@ class NoDataForPropertyError(DataCommonsError):
   """Raised when there is no data that meets the specified property filters."""
 
   default_message = "No available data for the specified property filters."
-
-
-VALID_SURFACE_HEADER_VALUES = ["mcp", r"mcp-[\d\.]+", "datagemma"]
-
-
-class InvalidSurfaceHeaderValueError(DataCommonsError):
-  """ 
-    The surface header value must be a surface known to the Data Commons team.
-    This value is used in the DC usage logs in Mixer.
-  """
-  default_message = "The surface header value should only to indicate a call made from Data Commons surfaces like the MCP server or DataGemma."