add range params

options_scraper.py

@@ -30,6 +30,16 @@ def parse_args(argv: list[str] | None = None) -> argparse.Namespace:
             " no --expiration is provided)."
         ),
     )
+    parser.add_argument(
+        "--exp-start",
+        type=int,
+        help="Start index (0-based) into the available expirations list.",
+    )
+    parser.add_argument(
+        "--exp-end",
+        type=int,
+        help="End index (0-based, exclusive) into the available expirations list.",
+    )
     parser.add_argument(
         "--calls-only",
         action="store_true",
@@ -44,6 +54,14 @@ def parse_args(argv: list[str] | None = None) -> argparse.Namespace:
 
     if args.calls_only and args.puts_only:
         parser.error("Use only one of --calls-only or --puts-only.")
+    if args.expiration and (args.exp_start is not None or args.exp_end is not None):
+        parser.error("Use either --expiration or the exp-start/exp-end range, not both.")
+    if args.all_expirations and (args.exp_start is not None or args.exp_end is not None):
+        parser.error("Use either --all-expirations or the exp-start/exp-end range, not both.")
+    if args.exp_start is not None and args.exp_start < 0:
+        parser.error("--exp-start must be non-negative.")
+    if args.exp_end is not None and args.exp_end < 0:
+        parser.error("--exp-end must be non-negative.")
 
     return args
 
@@ -53,6 +71,8 @@ def pick_expirations(
     requested: str | None,
     include_all: bool,
     default_limit: int | None,
+    range_start: int | None,
+    range_end: int | None,
 ) -> tuple[list[str], list[str]]:
     available = list(ticker.options or [])
     if not available:
@@ -64,6 +84,17 @@ def pick_expirations(
                 f"Expiration {requested!r} not in available dates: {', '.join(available)}"
             )
         targets = [requested]
+    elif range_start is not None or range_end is not None:
+        start = range_start or 0
+        end = range_end if range_end is not None else len(available)
+        if start >= len(available):
+            raise ValueError(
+                f"--exp-start {start} is beyond available expirations (max index {len(available) - 1})."
+            )
+        end = min(end, len(available))
+        if start >= end:
+            raise ValueError("--exp-start must be less than --exp-end.")
+        targets = available[start:end]
     elif include_all:
         targets = available
     else:
@@ -113,12 +144,19 @@ def main(argv: list[str] | None = None) -> int:
     default_limit = (
         DEFAULT_EXPIRATION_LIMIT if args.expiration is None and not args.all_expirations else None
     )
+    range_start = args.exp_start
+    range_end = args.exp_end
 
     ticker = yf.Ticker(args.symbol)
 
     try:
         target_expirations, available_expirations = pick_expirations(
-            ticker, args.expiration, include_all_expirations, default_limit
+            ticker,
+            args.expiration,
+            include_all_expirations,
+            default_limit,
+            range_start,
+            range_end,
         )
     except (ValueError, RuntimeError) as exc:
         print(f"error: {exc}", file=sys.stderr)