Fixed jdk path (#141)

## Issue
The new version of the snap relies on the jdk of the snap environment
instead of the one bundled by OpenSearch.
This PR replaces the path of the JDK by the correct one

lib/charms/opensearch/v0/opensearch_distro.py

@@ -32,6 +32,7 @@
     OpenSearchStartTimeoutError,
 )
 from charms.opensearch.v0.opensearch_internal_data import Scope
+from tenacity import retry, stop_after_attempt, wait_fixed
 
 # The unique Charmhub library identifier, never change it
 LIBID = "7145c219467d43beb9c566ab4a72c454"
@@ -317,6 +318,7 @@ def write_file(self, path: str, data: str, override: bool = True):
             f.write(data)
 
     @staticmethod
+    @retry(stop=stop_after_attempt(3), wait=wait_fixed(0.5), reraise=True)
     def _run_cmd(command: str, args: str = None, stdin: str = None) -> str:
         """Run command.
 
@@ -362,6 +364,7 @@ def _build_paths(self) -> Paths:
     def _set_env_variables(self):
         """Set the necessary environment variables."""
         os.environ["OPENSEARCH_HOME"] = self.paths.home
+        os.environ["JAVA_HOME"] = self.paths.jdk
         os.environ["OPENSEARCH_JAVA_HOME"] = self.paths.jdk
         os.environ["OPENSEARCH_PATH_CONF"] = self.paths.conf
         os.environ["OPENSEARCH_TMPDIR"] = self.paths.tmp

src/opensearch.py

@@ -131,7 +131,7 @@ def _build_paths(self) -> Paths:
             conf=f"{self._SNAP_DATA}/etc/opensearch",
             data=f"{self._SNAP_COMMON}/var/lib/opensearch",
             logs=f"{self._SNAP_COMMON}/var/log/opensearch",
-            jdk=f"{self._SNAP}/usr/share/opensearch/jdk",
+            jdk=f"{self._SNAP}/usr/lib/jvm/java-17-openjdk-amd64",
             tmp=f"{self._SNAP_COMMON}/usr/share/tmp",
             bin=f"{self._SNAP}/usr/share/opensearch/bin",
         )