Update launcher script and launchers (#212)

Author: Secrus

src/installer/_scripts/t32.exe

@@ -1,10 +1,15 @@
+from __future__ import annotations
+
 import asyncio
+import io
 import pathlib
 import sys
+import tarfile
+from typing import Any
 
 import httpx
 
-DOWNLOAD_URL = "https://bitbucket.org/vinay.sajip/simple_launcher/downloads/{}"
+DISTLIB_URL = "https://pypi.org/simple/distlib"
 VENDOR_DIR = (
     pathlib.Path(__file__)
     .parent.parent.joinpath("src", "installer", "_scripts")
@@ -23,18 +28,59 @@
 ]
 
 
-async def _download(client: httpx.AsyncClient, name: str) -> None:
-    url = DOWNLOAD_URL.format(name)
-    print(f"  Fetching {url}")
-    resp = await client.get(url)
-    data = await resp.aread()
-    VENDOR_DIR.joinpath(name).write_bytes(data)
+async def _get_distlib_page(client: httpx.AsyncClient) -> Any:
+    resp = await client.get(
+        DISTLIB_URL,
+        headers={"ACCEPT": "application/vnd.pypi.simple.v1+json"},
+        follow_redirects=True,
+    )
+    return resp.json()
+
+
+def _get_link_from_response(json_response: dict[str, Any]) -> tuple[str, str] | None:
+    version = max(version_str.split(".") for version_str in json_response["versions"])
+    filename = f'distlib-{".".join(version)}.tar.gz'
+    for file_info in json_response["files"]:
+        if file_info["filename"] == filename:
+            return file_info["url"], filename
+    return None
+
+
+async def _download_distlib(client: httpx.AsyncClient) -> bytes | None:
+    distlib_page = await _get_distlib_page(client)
+    data = None
+    if pair := _get_link_from_response(distlib_page):
+        url, filename = pair
+        print(f"  Fetching {filename}")
+        resp = await client.get(url)
+        data = await resp.aread()
+    return data
+
+
+def _get_launcher_path(names: list[str], launcher: str) -> str | None:
+    if paths := [name for name in names if launcher in name]:
+        return paths[0]
+    return None
+
+
+def _unpack_launchers_to_dir(distlib_tar: bytes) -> None:
+    print("Unpacking launchers")
+    with tarfile.open(fileobj=io.BytesIO(distlib_tar)) as file:
+        for launcher_name in LAUNCHERS:
+            if (path := _get_launcher_path(file.getnames(), launcher_name)) and (
+                launcher := file.extractfile(path)
+            ):
+                print(f"  Unpacking {launcher_name}")
+                VENDOR_DIR.joinpath(launcher_name).write_bytes(launcher.read())
 
 
 async def main() -> None:
     print(f"Downloading into {VENDOR_DIR} ...")
     async with httpx.AsyncClient() as client:
-        await asyncio.gather(*(_download(client, name) for name in LAUNCHERS))
+        data = await _download_distlib(client)
+    if data is not None:
+        _unpack_launchers_to_dir(data)
+    print("Scripts update failed!")
 
 
 def _patch_windows() -> None: