Handle GitHub Refresh Token request errors

httpx_oauth/clients/github.py

@@ -1,9 +1,10 @@
+import urllib.parse
 from typing import Any, Dict, List, Optional, Tuple, TypedDict, cast
 
 import httpx
 
 from httpx_oauth.errors import GetIdEmailError
-from httpx_oauth.oauth2 import BaseOAuth2
+from httpx_oauth.oauth2 import BaseOAuth2, OAuth2Token, RefreshTokenError
 
 AUTHORIZE_ENDPOINT = "https://github.com/login/oauth/authorize"
 ACCESS_TOKEN_ENDPOINT = "https://github.com/login/oauth/access_token"
@@ -47,6 +48,33 @@ def __init__(
             base_scopes=scopes,
         )
 
+    async def refresh_token(self, refresh_token: str):
+        assert self.refresh_token_endpoint is not None
+        async with self.get_httpx_client() as client:
+            response = await client.post(
+                self.refresh_token_endpoint,
+                data={
+                    "grant_type": "refresh_token",
+                    "refresh_token": refresh_token,
+                    "client_id": self.client_id,
+                    "client_secret": self.client_secret,
+                },
+                headers=self.request_headers,
+            )
+
+            content_type = response.headers.get("content-type", "")
+            if content_type.startswith("application/json"):
+                data = response.json()
+            # GitHub sends errors with a 200 status code
+            # and a form-urlencoded content type 😕
+            elif content_type.startswith("application/x-www-form-urlencoded"):
+                data = urllib.parse.parse_qs(response.text)
+
+            if response.status_code >= 400 or "error" in data:
+                raise RefreshTokenError(data)
+
+            return OAuth2Token(data)
+
     async def get_id_email(self, token: str) -> Tuple[str, Optional[str]]:
         async with httpx.AsyncClient(
             headers={**self.request_headers, "Authorization": f"token {token}"}

tests/mock/github_success_refresh_token.json

@@ -0,0 +1,8 @@
+{
+    "access_token": "ghu_XXX",
+    "expires_in": 28800,
+    "refresh_token": "ghr_XXX",
+    "refresh_token_expires_in": 15897600,
+    "scope": "",
+    "token_type": "bearer"
+}

tests/test_clients_github.py

@@ -1,11 +1,13 @@
 import re
+from urllib.parse import urlencode
 
 import pytest
 import respx
 from httpx import Response
 
 from httpx_oauth.clients.github import EMAILS_ENDPOINT, PROFILE_ENDPOINT, GitHubOAuth2
 from httpx_oauth.errors import GetIdEmailError
+from httpx_oauth.oauth2 import OAuth2Token, RefreshTokenError
 
 client = GitHubOAuth2("CLIENT_ID", "CLIENT_SECRET")
 
@@ -26,6 +28,52 @@ def test_github_oauth2():
 emails_response = [{"email": "[email protected]"}]
 
 
+class TestGitHubRefreshToken:
+    @pytest.mark.asyncio
+    @respx.mock
+    async def test_refresh_token(self, load_mock, get_respx_call_args):
+        request = respx.post(client.refresh_token_endpoint).mock(
+            return_value=Response(200, json=load_mock("github_success_refresh_token"))
+        )
+        access_token = await client.refresh_token("REFRESH_TOKEN")
+
+        url, headers, content = await get_respx_call_args(request)
+        assert headers["Content-Type"] == "application/x-www-form-urlencoded"
+        assert headers["Accept"] == "application/json"
+        assert "grant_type=refresh_token" in content
+        assert "refresh_token=REFRESH_TOKEN" in content
+        assert "client_id=CLIENT_ID" in content
+        assert "client_secret=CLIENT_SECRET" in content
+
+        assert type(access_token) == OAuth2Token
+        assert "access_token" in access_token
+        assert "token_type" in access_token
+        assert access_token.is_expired() is False
+
+    @pytest.mark.asyncio
+    @respx.mock
+    async def test_refresh_token_error(self, load_mock):
+        error_response = {
+            "error": "bad_refresh_token",
+            "error_description": "The refresh token passed is incorrect or expired.",
+            "error_uri": "https://docs.github.com",
+        }
+        error_response_encoded = urlencode(error_response)
+
+        respx.post(client.refresh_token_endpoint).mock(
+            return_value=Response(
+                200,
+                headers={"content-type": "application/x-www-form-urlencoded"},
+                content=error_response_encoded,
+            )
+        )
+
+        with pytest.raises(RefreshTokenError) as excinfo:
+            await client.refresh_token("REFRESH_TOKEN")
+        assert isinstance(excinfo.value.args[0], dict)
+        assert "error" in excinfo.value.args[0]
+
+
 class TestGitHubGetIdEmail:
     @pytest.mark.asyncio
     @respx.mock