Script to install nightly torchmonarch and torch (#778)

Summary:
Can be run as (once commited):
`curl https://raw.githubusercontent.com/meta-pytorch/monarch/refs/heads/main/scripts/install-nightly.py | python`

Was initially live vibe-coded in https://claude.ai/share/399c5406-1adc-474d-a6c8-340fd076664d
And eventually converted to python in https://claude.ai/share/4aa24968-8048-4a36-ae67-95fc99fd7be8
But in neither cases could make it produce something workable

Pull Request resolved: #778

Reviewed By: dcci

Differential Revision: D79754252

Pulled By: malfet

fbshipit-source-id: 87a71df9bcce0b7d43f68bfea26d049214626092

Author: malfet

scripts/install_nightly.py

@@ -0,0 +1,84 @@
+#!/usr/bin/env python3
+# Run me as:
+# curl https://raw.githubusercontent.com/meta-pytorch/monarch/refs/heads/main/scripts/install-nightly.py | python
+
+import json
+import subprocess
+import sys
+import urllib.request
+
+
+def get_latest_version(package_name: str) -> str:
+    """Get latest version from PyPI"""
+    api_url = f"https://pypi.org/pypi/{package_name}/json"
+
+    try:
+        with urllib.request.urlopen(api_url) as response:
+            data = json.loads(response.read().decode("utf-8"))
+            return data["info"]["version"]
+    except Exception as e:
+        print(f"Failed to fetch version for {package_name}: {e}", file=sys.stderr)
+        sys.exit(1)
+
+
+def get_torch_release_version() -> str:
+    """Get PyTorch version numbers"""
+    version_url = (
+        "https://raw.githubusercontent.com/pytorch/pytorch/refs/heads/main/version.txt"
+    )
+    try:
+        with urllib.request.urlopen(version_url) as response:
+            return response.read().decode("utf-8").split("a")[0]
+    except Exception as e:
+        print(f"Failed to fetch torch version: {e}", file=sys.stderr)
+        sys.exit(1)
+
+
+def convert_version_for_torch(version: str) -> str:
+    """Convert version format for torch (YYYY.M.D or YYYY.MM.DD -> YYYYMMDD)"""
+    # Split the version into components
+    year, month, day = [int(x) for x in version.split(".")]
+
+    return f"{year}{month:02}{day:02}"
+
+
+def main() -> None:
+    """Main function"""
+    print("Starting torchmonarch-nightly installation script")
+
+    # Get latest version
+    torchmonarch_version = get_latest_version("torchmonarch-nightly")
+    print(f"Latest torchmonarch-nightly version: {torchmonarch_version}")
+
+    # Convert version for torch
+    torch_release_version = get_torch_release_version()
+    torch_date = convert_version_for_torch(torchmonarch_version)
+    torch_version = f"{torch_release_version}.dev{torch_date}"
+
+    print(f"Corresponding torch version: {torch_version}")
+
+    # Construct the pip install command arguments
+    pip_command = [
+        sys.executable,
+        "-m",
+        "pip",
+        "install",
+        f"torchmonarch-nightly=={torchmonarch_version}",
+        f"torch=={torch_version}",
+        "--pre",
+        "--extra-index-url",
+        "https://download.pytorch.org/whl/nightly/cu128",
+    ]
+
+    print(f"Executing command:\n\t{' '.join(pip_command)}\n\n")
+
+    # Execute the command
+    subprocess.check_call(pip_command)
+    print("Installation completed successfully!")
+    print("Installed packages:")
+    print(f"  - torchmonarch-nightly=={torchmonarch_version}")
+    print(f"  - torch=={torch_version}")
+
+
+if __name__ == "__main__":
+    main()