fix: check if message_id is truthy instead of None before using it

Dockerfile

@@ -6,7 +6,8 @@ COPY ./requirements.txt ./requirements.txt
 
 RUN pip install --upgrade pip && pip install -r ./requirements.txt
 
-COPY ./main.py ./main.py
-COPY ./entrypoint.sh ./entrypoint.sh
+WORKDIR /action
 
-ENTRYPOINT ["./entrypoint.sh"]
+COPY ./main.py ./main.py
+
+ENTRYPOINT ["python", "/action/main.py"]

entrypoint.sh

@@ -1,3 +0,0 @@
-#!/bin/bash
-
-python ./main.py "$@"

main.py

@@ -70,7 +70,7 @@ if __name__ == "__main__":
         ],
     )
 
-    if message_id is not None:
+    if message_id:
         previous_message_data = httpx.get(f"{webhook_url}/messages/{message_id}").json()
 
         response = httpx.patch(
@@ -82,7 +82,10 @@ if __name__ == "__main__":
         response = httpx.post(f"{webhook_url}?wait=true", json={"embeds": [embed_data]})
         message_id = response.json()["id"]
 
-    outputs_path = os.environ.get("GITHUB_ENV")
+    outputs_path = os.environ.get("GITHUB_OUTPUT")
+
+    if not outputs_path:
+        raise RuntimeError("Cannot write to outputs, no GITHUB_ENV set.")
 
     with open(outputs_path, "a", encoding="utf-8") as outputs_file:
-        outputs_file.write(f"message-id={message_id}")
+        outputs_file.write(f"message-id={message_id}\n")