From 3aa9cf627d5c48d8e317348ee11e65b2bf370b82 Mon Sep 17 00:00:00 2001
From: Steve Clarke <84364906+s7clarke10@users.noreply.github.com>
Date: Fri, 7 Jul 2023 15:56:32 +1200
Subject: [PATCH 1/2] Supporting optional headers for oauth.

---
 singer_sdk/authenticators.py | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/singer_sdk/authenticators.py b/singer_sdk/authenticators.py
index ac9bb2807..cf74cac80 100644
--- a/singer_sdk/authenticators.py
+++ b/singer_sdk/authenticators.py
@@ -358,6 +358,7 @@ def __init__(
         auth_endpoint: str | None = None,
         oauth_scopes: str | None = None,
         default_expiration: int | None = None,
+        oauth_headers: dict | None = None,
     ) -> None:
         """Create a new authenticator.
 
@@ -377,6 +378,10 @@ def __init__(
         self.refresh_token: str | None = None
         self.last_refreshed: datetime | None = None
         self.expires_in: int | None = None
+        if self._auth_headers is None:
+            self._auth_headers = {}
+        if oauth_headers:
+            self._auth_headers.update(oauth_headers)
 
     @property
     def auth_headers(self) -> dict:
@@ -499,6 +504,7 @@ def update_access_token(self) -> None:
         auth_request_payload = self.oauth_request_payload
         token_response = requests.post(
             self.auth_endpoint,
+            headers=self._auth_headers,
             data=auth_request_payload,
             timeout=60,
         )
@@ -512,7 +518,7 @@ def update_access_token(self) -> None:
 
         token_json = token_response.json()
         self.access_token = token_json["access_token"]
-        self.expires_in = token_json.get("expires_in", self._default_expiration)
+        self.expires_in = int(token_json.get("expires_in", self._default_expiration))
         if self.expires_in is None:
             self.logger.debug(
                 "No expires_in receied in OAuth response and no "

From 430a2280a1922e3ae2adca5c8b44ee1900856a88 Mon Sep 17 00:00:00 2001
From: Steve Clarke <84364906+s7clarke10@users.noreply.github.com>
Date: Mon, 10 Jul 2023 11:54:39 +1200
Subject: [PATCH 2/2] Optional OAuth only Headers with tests for None

---
 singer_sdk/authenticators.py | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/singer_sdk/authenticators.py b/singer_sdk/authenticators.py
index cf74cac80..61382daba 100644
--- a/singer_sdk/authenticators.py
+++ b/singer_sdk/authenticators.py
@@ -367,21 +367,19 @@ def __init__(
             auth_endpoint: The OAuth 2.0 authorization endpoint.
             oauth_scopes: A comma-separated list of OAuth scopes.
             default_expiration: Default token expiry in seconds.
+            oauth_headers: An optional dict of headers required to get a token.
         """
         super().__init__(stream=stream)
         self._auth_endpoint = auth_endpoint
         self._default_expiration = default_expiration
         self._oauth_scopes = oauth_scopes
+        self._oauth_headers = oauth_headers or {}
 
         # Initialize internal tracking attributes
         self.access_token: str | None = None
         self.refresh_token: str | None = None
         self.last_refreshed: datetime | None = None
         self.expires_in: int | None = None
-        if self._auth_headers is None:
-            self._auth_headers = {}
-        if oauth_headers:
-            self._auth_headers.update(oauth_headers)
 
     @property
     def auth_headers(self) -> dict:
@@ -504,7 +502,7 @@ def update_access_token(self) -> None:
         auth_request_payload = self.oauth_request_payload
         token_response = requests.post(
             self.auth_endpoint,
-            headers=self._auth_headers,
+            headers=self._oauth_headers,
             data=auth_request_payload,
             timeout=60,
         )
@@ -518,7 +516,8 @@ def update_access_token(self) -> None:
 
         token_json = token_response.json()
         self.access_token = token_json["access_token"]
-        self.expires_in = int(token_json.get("expires_in", self._default_expiration))
+        expiration = token_json.get("expires_in", self._default_expiration)
+        self.expires_in = int(expiration) if expiration else None
         if self.expires_in is None:
             self.logger.debug(
                 "No expires_in receied in OAuth response and no "