New OAuth2AuthManager

mkdocs/docs/configuration.md

@@ -388,6 +388,8 @@ The RESTCatalog supports pluggable authentication via the `auth` configuration b
 
 - `noop`: No authentication (no Authorization header sent).
 - `basic`: HTTP Basic authentication.
+- `oauth2`: OAuth2 client credentials flow.
+- `legacyoauth2`: Legacy OAuth2 client credentials flow (Deprecated and will be removed in PyIceberg 1.0.0)
 - `custom`: Custom authentication manager (requires `auth.impl`).
 
 ###### Configuration Properties
@@ -410,9 +412,10 @@ catalog:
 
 | Property         | Required | Description                                                                                     |
 |------------------|----------|-------------------------------------------------------------------------------------------------|
-| `auth.type`      | Yes      | The authentication type to use (`noop`, `basic`, or `custom`).                       |
+| `auth.type`      | Yes      | The authentication type to use (`noop`, `basic`, `oauth2`, or `custom`).                       |
 | `auth.impl`      | Conditionally | The fully qualified class path for a custom AuthManager. Required if `auth.type` is `custom`. |
 | `auth.basic`     | If type is `basic` | Block containing `username` and `password` for HTTP Basic authentication.           |
+| `auth.oauth2`    | If type is `oauth2` | Block containing OAuth2 configuration (see below).                                 |
 | `auth.custom`    | If type is `custom` | Block containing configuration for the custom AuthManager.                          |
 
 ###### Examples
@@ -434,6 +437,20 @@ auth:
     password: mypass
 ```
 
+OAuth2 Authentication:
+
+```yaml
+auth:
+  type: oauth2
+  oauth2:
+    client_id: my-client-id
+    client_secret: my-client-secret
+    token_url: https://auth.example.com/oauth/token
+    scope: read
+    refresh_margin: 60         # (optional) seconds before expiry to refresh
+    expires_in: 3600           # (optional) fallback if server does not provide
+```
+
 Custom Authentication:
 
 ```yaml
@@ -449,7 +466,7 @@ auth:
 
 - If `auth.type` is `custom`, you **must** specify `auth.impl` with the full class path to your custom AuthManager.
 - If `auth.type` is not `custom`, specifying `auth.impl` is not allowed.
-- The configuration block under each type (e.g., `basic`, `custom`) is passed as keyword arguments to the corresponding AuthManager.
+- The configuration block under each type (e.g., `basic`, `oauth2`, `custom`) is passed as keyword arguments to the corresponding AuthManager.
 
 <!-- markdown-link-check-enable-->
 

pyiceberg/catalog/rest/auth.py

@@ -17,9 +17,12 @@
 
 import base64
 import importlib
+import threading
+import time
 from abc import ABC, abstractmethod
 from typing import Any, Dict, Optional, Type
 
+import requests
 from requests import HTTPError, PreparedRequest, Session
 from requests.auth import AuthBase
 
@@ -119,6 +122,95 @@ def auth_header(self) -> str:
         return f"Bearer {self._token}"
 
 
+class OAuth2TokenProvider:
+    """Thread-safe OAuth2 token provider with token refresh support."""
+
+    client_id: str
+    client_secret: str
+    token_url: str
+    scope: Optional[str]
+    refresh_margin: int
+    expires_in: Optional[int]
+
+    _token: Optional[str]
+    _expires_at: int
+    _lock: threading.Lock
+
+    def __init__(
+        self,
+        client_id: str,
+        client_secret: str,
+        token_url: str,
+        scope: Optional[str] = None,
+        refresh_margin: int = 60,
+        expires_in: Optional[int] = None,
+    ):
+        self.client_id = client_id
+        self.client_secret = client_secret
+        self.token_url = token_url
+        self.scope = scope
+        self.refresh_margin = refresh_margin
+        self.expires_in = expires_in
+
+        self._token = None
+        self._expires_at = 0
+        self._lock = threading.Lock()
+
+    def _refresh_token(self) -> None:
+        data = {
+            "grant_type": "client_credentials",
+            "client_id": self.client_id,
+            "client_secret": self.client_secret,
+        }
+        if self.scope:
+            data["scope"] = self.scope
+
+        response = requests.post(self.token_url, data=data)
+        response.raise_for_status()
+        result = response.json()
+
+        self._token = result["access_token"]
+        expires_in = result.get("expires_in", self.expires_in)
+        if expires_in is None:
+            raise ValueError(
+                "The expiration time of the Token must be provided by the Server in the Access Token Response in `expires_in` field, or by the PyIceberg Client."
+            )
+        self._expires_at = time.time() + expires_in - self.refresh_margin
+
+    def get_token(self) -> str:
+        with self._lock:
+            if not self._token or time.time() >= self._expires_at:
+                self._refresh_token()
+            if self._token is None:
+                raise ValueError("Authorization token is None after refresh")
+            return self._token
+
+
+class OAuth2AuthManager(AuthManager):
+    """Auth Manager implementation that supports OAuth2 as defined in IETF RFC6749."""
+
+    def __init__(
+        self,
+        client_id: str,
+        client_secret: str,
+        token_url: str,
+        scope: Optional[str] = None,
+        refresh_margin: int = 60,
+        expires_in: Optional[int] = None,
+    ):
+        self.token_provider = OAuth2TokenProvider(
+            client_id,
+            client_secret,
+            token_url,
+            scope,
+            refresh_margin,
+            expires_in,
+        )
+
+    def auth_header(self) -> str:
+        return f"Bearer {self.token_provider.get_token()}"
+
+
 class AuthManagerAdapter(AuthBase):
     """A `requests.auth.AuthBase` adapter that integrates an `AuthManager` into a `requests.Session` to automatically attach the appropriate Authorization header to every request.
 
@@ -197,3 +289,4 @@ def create(cls, class_or_name: str, config: Dict[str, Any]) -> AuthManager:
 AuthManagerFactory.register("noop", NoopAuthManager)
 AuthManagerFactory.register("basic", BasicAuthManager)
 AuthManagerFactory.register("legacyoauth2", LegacyOAuth2AuthManager)
+AuthManagerFactory.register("oauth2", OAuth2AuthManager)

tests/catalog/test_rest.py

@@ -1646,6 +1646,40 @@ def test_rest_catalog_with_unsupported_auth_type() -> None:
     assert "Could not load AuthManager class for 'unsupported'" in str(e.value)
 
 
+def test_rest_catalog_with_oauth2_auth_type(requests_mock: Mocker) -> None:
+    requests_mock.post(
+        f"{TEST_URI}oauth2/token",
+        json={
+            "access_token": "MTQ0NjJkZmQ5OTM2NDE1ZTZjNGZmZjI3",
+            "token_type": "Bearer",
+            "expires_in": 3600,
+            "refresh_token": "IwOGYzYTlmM2YxOTQ5MGE3YmNmMDFkNTVk",
+            "scope": "read",
+        },
+        status_code=200,
+    )
+    requests_mock.get(
+        f"{TEST_URI}v1/config",
+        json={"defaults": {}, "overrides": {}},
+        status_code=200,
+    )
+    # Given
+    catalog_properties = {
+        "uri": TEST_URI,
+        "auth": {
+            "type": "oauth2",
+            "oauth2": {
+                "client_id": "some_client_id",
+                "client_secret": "some_client_secret",
+                "token_url": f"{TEST_URI}oauth2/token",
+                "scope": "read",
+            },
+        },
+    }
+    catalog = RestCatalog("rest", **catalog_properties)  # type: ignore
+    assert catalog.uri == TEST_URI
+
+
 EXAMPLE_ENV = {"PYICEBERG_CATALOG__PRODUCTION__URI": TEST_URI}