fix: replace Playwright post() with httpx legacy API, fix session_file Path coercion and comment URL check

smoke test confirmed: post via /api/submit + comment via /api/comment both working with modhash + session cookies

app/services/platforms/reddit_comment.py

@@ -134,8 +134,8 @@ class RedditCommentStrategy(PostingStrategy):
         client = RedditClient(session_file=session_file)
         comment_url = client.comment(thread_id=thread_id, body=body)
 
-        # Reddit comment() may return empty URL; reconstruct from thread_id
-        if not comment_url:
+        # Reddit comment() may return bare domain or empty; reconstruct from thread_id
+        if not comment_url or comment_url.rstrip("/") in ("https://reddit.com", "https://www.reddit.com"):
             comment_url = f"https://www.reddit.com/r/{target}/comments/{thread_id}/"
 
         return PostResult(url=comment_url, metadata={"thread_id": thread_id})

app/services/reddit/client.py

@@ -24,7 +24,7 @@ USER_AGENT = "Mozilla/5.0 (X11; Linux x86_64) Chrome/124.0.0.0"
 class RedditClient:
     def __init__(self, session_file: Path | None = None) -> None:
         settings = get_settings()
-        self._session_file = session_file or Path(settings.reddit_session_file)
+        self._session_file = Path(session_file) if session_file else Path(settings.reddit_session_file)
         ensure_valid_session(self._session_file)
         self.cookies = load_cookies(self._session_file)
         self.headers = {"User-Agent": USER_AGENT}
@@ -43,43 +43,36 @@ class RedditClient:
         return self._modhash
 
     def post(self, sub: str, title: str, body: str, flair: str | None = None) -> str:
-        """Submit a text post via Playwright (xvfb-run). Returns the permalink."""
-        settings = get_settings()
-        cmd = [
-            "xvfb-run", "--auto-servernum",
-            sys.executable, str(_POST_SCRIPT),
-            "--sub", sub,
-            "--title", title,
-            "--body", body,
-            "--yes",
-        ]
-        if flair:
-            cmd += ["--flair", flair]
-
-        result = subprocess.run(
-            cmd,
-            capture_output=True,
-            text=True,
-            timeout=180,
-            env={
-                **__import__("os").environ,
-                "REDDIT_SESSION_FILE": str(self._session_file),
-            },
+        """Submit a text post via Reddit legacy API (httpx). Returns the permalink."""
+        data = {
+            "api_type": "json",
+            "kind": "self",
+            "sr": sub,
+            "title": title,
+            "text": body,
+            "uh": self.modhash,
+            "sendreplies": "true",
+            "nsfw": "false",
+            "spoiler": "false",
+        }
+        resp = httpx.post(
+            "https://www.reddit.com/api/submit",
+            cookies=self.cookies,
+            headers=self.headers,
+            data=data,
+            timeout=30,
         )
-        if result.returncode != 0:
+        resp.raise_for_status()
+        result = resp.json()
+        errors = result.get("json", {}).get("errors", [])
+        if errors:
+            raise RuntimeError(f"Post to r/{sub} failed: {errors}")
+        url = result.get("json", {}).get("data", {}).get("url", "")
+        if not url:
             raise RuntimeError(
-                f"Post to r/{sub} failed (exit {result.returncode}):\n"
-                f"STDOUT:\n{result.stdout}\n"
-                f"STDERR:\n{result.stderr}"
+                f"Post to r/{sub} may have failed — no URL in response:\n{result}"
             )
-        for line in result.stdout.splitlines():
-            if line.startswith("Posted:"):
-                url = line.split("Posted:", 1)[-1].strip()
-                return url
-        raise RuntimeError(
-            f"Post to r/{sub} may have failed — no 'Posted:' line in output.\n"
-            f"Full stdout:\n{result.stdout}"
-        )
+        return url
 
     def comment(self, thread_id: str, body: str) -> str:
         """Post a top-level comment to a thread. Returns the permalink."""