Make tycho_client a python package, small bugfixes

testing/tycho-client/tycho_client/tycho_db.py

@@ -0,0 +1,48 @@
+from protosim_py import TychoDB
+
+
+class TychoDBSingleton:
+    """
+    A singleton wrapper around the TychoDB class.
+
+    This class ensures that there is only one instance of TychoDB throughout the lifetime of the program,
+    avoiding the overhead of creating multiple instances.
+    """
+
+    _instance = None
+
+    @classmethod
+    def initialize(cls, tycho_http_url: str):
+        """
+        Initialize the TychoDB instance with the given URLs.
+
+        Parameters
+        ----------
+        tycho_http_url : str
+            The URL of the Tycho HTTP server.
+
+        """
+        cls._instance = TychoDB(tycho_http_url=tycho_http_url)
+
+    @classmethod
+    def get_instance(cls) -> TychoDB:
+        """
+        Retrieve the singleton instance of TychoDB.
+
+        If the TychoDB instance does not exist, it creates a new one.
+        If it already exists, it returns the existing instance.
+
+        Returns
+        -------
+        TychoDB
+            The singleton instance of TychoDB.
+        """
+        if cls._instance is None:
+            raise ValueError(
+                "TychoDB instance not initialized. Call initialize() first."
+            )
+        return cls._instance
+
+    @classmethod
+    def clear_instance(cls):
+        cls._instance = None