ci: use persistent local model cache on self-hosted runners (#266)

* ci: use persistent local model cache instead of actions/cache

Self-hosted runners are persistent VMs, so there's no need to use
actions/cache to transfer ~2GB of model files via GitHub's cache
service on every CI run. Instead, point AUDIO_SEPARATOR_MODEL_DIR
to /opt/audio-separator-models/ where models are pre-downloaded
by the runner startup script and persist across job runs.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* chore: clean up duplicate import and sort imports in integration test

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: beveradb

.github/workflows/run-integration-tests.yaml

@@ -25,7 +25,10 @@ jobs:
     if: needs.changes.outputs.should_run == 'true'
     runs-on: self-hosted
     env:
-      AUDIO_SEPARATOR_MODEL_DIR: ${{ github.workspace }}/models
+      # Use persistent local directory on self-hosted runners instead of actions/cache.
+      # Models are pre-downloaded to this path by the runner startup script, so there's
+      # no need to download ~2GB of models on every CI run.
+      AUDIO_SEPARATOR_MODEL_DIR: /opt/audio-separator-models
 
     steps:
       - name: Checkout project
@@ -56,25 +59,18 @@ jobs:
           python-version: '3.13'
           cache: poetry
 
-      - name: Create models directory
-        run: mkdir -p $AUDIO_SEPARATOR_MODEL_DIR
-
-      - name: Cache models directory
-        uses: actions/cache@v3
-        id: model-cache
-        with:
-          path: ${{ env.AUDIO_SEPARATOR_MODEL_DIR }}
-          key: model-cache-${{ hashFiles('tests/integration/test_cli_integration.py') }}
-          restore-keys: model-cache-
-
       - name: Install Poetry dependencies
         run: poetry install -E cpu
 
-      - name: Display model cache status
+      - name: Verify pre-cached models
         run: |
-          echo "Model cache hit: ${{ steps.model-cache.outputs.cache-hit == 'true' }}"
           echo "Models directory contents:"
-          ls -la $AUDIO_SEPARATOR_MODEL_DIR || echo "Directory empty or doesn't exist"
+          ls -lh $AUDIO_SEPARATOR_MODEL_DIR
+          MODEL_COUNT=$(ls -1 $AUDIO_SEPARATOR_MODEL_DIR | wc -l)
+          echo "Total files: $MODEL_COUNT"
+          if [ "$MODEL_COUNT" -lt 10 ]; then
+            echo "::warning::Expected at least 10 pre-cached model files, found $MODEL_COUNT"
+          fi
 
       - name: Run integration tests
         run: poetry run pytest -sv --cov=audio_separator --cov-report=xml tests/integration

tests/integration/test_cli_integration.py

@@ -1,9 +1,9 @@
 import os
 import subprocess
-import pytest
-from pathlib import Path
 import sys
-import os
+from pathlib import Path
+
+import pytest
 sys.path.append(os.path.dirname(os.path.dirname(__file__)))
 from utils import generate_reference_images, compare_images