Support HTTP Basic auth for OpenAPI tools

Author: Nana Oppong Ampofo

src/google/adk/tools/openapi_tool/auth/auth_helpers.py

@@ -14,6 +14,7 @@
 
 from __future__ import annotations
 
+import base64
 from typing import Any
 from typing import Dict
 from typing import List
@@ -391,12 +392,22 @@ def credential_to_param(
         and auth_credential.http
         and auth_credential.http.credentials
         and (
-            auth_credential.http.credentials.username
-            or auth_credential.http.credentials.password
+            auth_credential.http.credentials.username is not None
+            or auth_credential.http.credentials.password is not None
         )
     ):
-      # Basic Auth is explicitly NOT supported
-      raise NotImplementedError("Basic Authentication is not supported.")
+      username = auth_credential.http.credentials.username or ""
+      password = auth_credential.http.credentials.password or ""
+      encoded = base64.b64encode(f"{username}:{password}".encode()).decode()
+      param = ApiParameter(
+          original_name="Authorization",
+          param_location="header",
+          param_schema=Schema(type="string"),
+          description=auth_scheme.description or "Basic auth",
+          py_name=INTERNAL_AUTH_PREFIX + "Authorization",
+      )
+      kwargs = {param.py_name: f"Basic {encoded}"}
+      return param, kwargs
     else:
       raise ValueError("Invalid HTTP auth credentials")
 

tests/unittests/tools/openapi_tool/auth/test_auth_helper.py

@@ -12,6 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import base64
 from unittest.mock import patch
 
 from fastapi.openapi.models import APIKey
@@ -411,7 +412,7 @@ def test_credential_to_param_http_bearer():
   assert kwargs == {INTERNAL_AUTH_PREFIX + "Authorization": "Bearer test_token"}
 
 
-def test_credential_to_param_http_basic_not_supported():
+def test_credential_to_param_http_basic():
   auth_scheme = HTTPBase(scheme="basic")
   auth_credential = AuthCredential(
       auth_type=AuthCredentialTypes.HTTP,
@@ -421,10 +422,12 @@ def test_credential_to_param_http_basic_not_supported():
       ),
   )
 
-  with pytest.raises(
-      NotImplementedError, match="Basic Authentication is not supported."
-  ):
-    credential_to_param(auth_scheme, auth_credential)
+  param, kwargs = credential_to_param(auth_scheme, auth_credential)
+
+  expected = base64.b64encode(b"user:password").decode()
+  assert param.original_name == "Authorization"
+  assert param.param_location == "header"
+  assert kwargs == {INTERNAL_AUTH_PREFIX + "Authorization": f"Basic {expected}"}
 
 
 def test_credential_to_param_http_invalid_credentials_no_http():