Added CI to test CUDA C++ Extension Builds. (#99)

* Added CI integration.

* Updated requirements file.

* Installed NVIDIA CUDA toolkit on CI machine.

* Included apt-get update.

* No need to have CUDA available to build the extension.

* Added badge and updated README.

Author: vbharadwaj-bk

.github/workflows/requirements_cuda_ci.txt

@@ -0,0 +1,4 @@
+numpy==2.2.5
+torch==2.7.0 --index-url https://download.pytorch.org/whl/cu128
+pytest==8.3.5
+ninja==1.11.1.4

.github/workflows/verify_extension_build.yml

@@ -0,0 +1,36 @@
+name: OEQ CUDA C++ Extension Build Verification
+
+on:
+  push:
+    branches: [ "main" ] 
+  pull_request:
+    branches: [ "main" ]
+    types: [ labeled ]
+
+permissions:
+  contents: read
+
+jobs:
+  verify_cuda_extension:
+    if: ${{ github.event.label.name == 'ci-ready' || github.event_name != 'pull_request' }}
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v4
+    - name: Set up Python
+      uses: actions/setup-python@v5
+      with:
+        python-version: "3.10"
+        cache: 'pip'
+        cache-dependency-path: '**/requirements_cuda_ci.txt'
+    - name: Install dependencies
+      run: |
+        python -m pip install --upgrade pip
+        sudo apt-get update
+        sudo apt install nvidia-cuda-toolkit
+        pip install -r .github/workflows/requirements_cuda_ci.txt
+        pip install -e .
+
+    - name: Test extension build via import 
+      run: |
+        pytest tests/import_test.py -k test_import

README.md

@@ -1,4 +1,6 @@
 # OpenEquivariance
+[![OEQ CUDA C++ Extension Build Verification](https://github.com/PASSIONLab/OpenEquivariance/actions/workflows/verify_extension_build.yml/badge.svg?event=push)](https://github.com/PASSIONLab/OpenEquivariance/actions/workflows/verify_extension_build.yml)
+[![License](https://img.shields.io/badge/License-BSD_3--Clause-blue.svg)](https://opensource.org/licenses/BSD-3-Clause)
 
 [[Examples]](#show-me-some-examples) [[Installation]](#installation)
 [[Supported Tensor Products]](#tensor-products-we-accelerate)

openequivariance/extlib/__init__.py

@@ -24,7 +24,7 @@
     torch_sources = ['torch_tp_jit.cpp']
 
     include_dirs, extra_link_args = ['util'], None 
-    if torch.cuda.is_available() and torch.version.cuda:
+    if torch.version.cuda:
         extra_link_args = ['-Wl,--no-as-needed', '-lcuda', '-lcudart', '-lnvrtc']
 
         try:
@@ -36,7 +36,7 @@
             getLogger().info(str(e))
 
         extra_cflags.append("-DCUDA_BACKEND")
-    elif torch.cuda.is_available() and torch.version.hip:
+    elif torch.version.hip:
         extra_link_args = [ '-Wl,--no-as-needed', '-lhiprtc']
 
         def postprocess(kernel):