Feature/bwdo 809 implement lock clone cache

setup.py

@@ -38,6 +38,7 @@ def read_version():
         'pyyaml~=6.0',
         'rich>=14',
         'requests==2.31.0', # Docker SDK breaks on 2.32.0
+        'filelock==3.29.7',
         'repo_library @ git+https://github.com/rdkcentral/sc-repo-library.git@master',
         'git_flow_library @ git+https://github.com/rdkcentral/sc-git-flow-library.git@master',
         'sc_manifest_parser @ git+https://github.com/rdkcentral/sc-manifest-parser.git@main'

src/sc/clone/cloners/repo_cloner.py

@@ -18,7 +18,9 @@
 import shutil
 import subprocess
 import sys
+import time
 
+from filelock import SoftFileLock, Timeout
 from pydantic import BaseModel
 
 from .cloner import Cloner, RefType
@@ -29,6 +31,8 @@
 logger = logging.getLogger(__name__)
 
 REPO_CACHE_DIR = Path.home() / ".caches"
+CACHE_LOCK_PATH = REPO_CACHE_DIR / ".sc_lock"
+CACHE_MAX_WAIT = 300
 
 class RepoClonerConfig(BaseModel):
     """
@@ -74,8 +78,24 @@ def clone(self, directory: Path):
         - Parses the manifest to retrieve projects.
         - Initializes GitFlow for all unlocked projects.
         """
-        reference = self._cache() if self.config.cache else None
+        if self.config.cache:
+            self._clone_with_cache(directory)
+        else:
+            self._clone(directory)
+
+    def _clone_with_cache(self, directory: Path):
+        REPO_CACHE_DIR.mkdir(exist_ok=True)
+
+        lock = SoftFileLock(CACHE_LOCK_PATH)
+        self._acquire_cache_lock(lock)
 
+        try:
+            reference = self._cache()
+            self._clone(directory, reference)
+        finally:
+            lock.release()
+
+    def _clone(self, directory: Path, reference: Path | None = None):
         self._init_repo(directory=directory, reference=reference)
         RepoLibrary.sync(
             directory,
@@ -95,7 +115,6 @@ def _cache(self) -> Path:
         Returns:
             Path: The directory of the mirrored cache.
         """
-        REPO_CACHE_DIR.mkdir(exist_ok=True)
         manifest_hostname = self._get_manifest_hostname(self.config.uri)
         host_cache_dir = Path(REPO_CACHE_DIR / manifest_hostname)
         host_cache_dir.mkdir(exist_ok=True)
@@ -139,6 +158,40 @@ def _init_repo(self, directory: Path, mirror: bool = False, reference: Path | No
             logger.error(f"repo init error: {e}")
             sys.exit(1)
 
+    def _acquire_cache_lock(self, lock: SoftFileLock):
+        """Try to acquire cache lock. After a certain time bypass it."""
+        started = time.monotonic()
+        first_warning = False
+
+        logger.info("Acquiring cache lock.")
+        while True:
+            try:
+                lock.acquire(timeout=20)
+                logger.info("Cache lock acquired.")
+                return
+
+            except Timeout:
+                waited = int(time.monotonic() - started)
+                if waited < CACHE_MAX_WAIT:
+                    logger.info(
+                        f"Cache is in use by another process, waited {waited} seconds..."
+                    )
+
+                    if first_warning == False:
+                        logger.info(f"SC will wait for {CACHE_MAX_WAIT} seconds before bypassing.")
+                        logger.info(
+                            "The cache is user specific, if you believe there is no way your cache "
+                            f"should be in use you could try deleting the lock: {CACHE_LOCK_PATH}")
+                        first_warning = True
+                else:
+                    logger.warning(
+                        f"Cache remained locked past the set wait time of {CACHE_MAX_WAIT} seconds. "
+                        "Force proceeding without acquiring cache lock..."
+                    )
+                    lock.break_lock()
+                    lock.acquire()
+                    return
+
     def _get_manifest_hostname(self, url: str) -> str:
         """Extracts the hostname from a given URL.