feat: override an existing system if a system with the same name is u… (

#244)

backend/zeno_backend/database/delete.py

@@ -195,3 +195,33 @@ def report_org(report_id: int, organization: Organization):
         "AND report_id = %s;",
         [organization.id, report_id],
     )
+
+
+def system(project_uuid: str, system_name: str):
+    """Delete a system from a project.
+
+    Args:
+        project_uuid (str): id of the project to delete a system from.
+        system_name (str): name of the system to be deleted.
+    """
+    with Database() as db:
+        columns = db.execute_return(
+            sql.SQL("SELECT column_id FROM {} WHERE model = %s;").format(
+                sql.Identifier(f"{project_uuid}_column_map")
+            ),
+            [system_name],
+        )
+        for column in columns:
+            db.execute(
+                sql.SQL("ALTER TABLE {} DROP COLUMN {};").format(
+                    sql.Identifier(project_uuid),
+                    sql.Identifier(column[0]),
+                )
+            )
+            db.execute(
+                sql.SQL("DELETE FROM {} WHERE column_id = %s;").format(
+                    sql.Identifier(f"{project_uuid}_column_map")
+                ),
+                [column[0]],
+            )
+        db.commit()

backend/zeno_backend/database/select.py

@@ -1602,3 +1602,31 @@ def filtered_short_string_column_values(
         short_ret.append(loc_str)
 
     return short_ret
+
+
+def system_exists(project_uuid: str, system_name: str) -> bool:
+    """Check whether a system exists for a project.
+
+    Args:
+        project_uuid (str): ID of the project.
+        system_name (str): name of the system.
+
+
+    Returns:
+        bool: whether the system exists.
+
+
+    Raises:
+        Exception: something went wrong while checking whether the system exists.
+    """
+    db = Database()
+    exists = db.connect_execute_return(
+        sql.SQL("SELECT EXISTS(SELECT 1 FROM {} " "WHERE model = %s);").format(
+            sql.Identifier(f"{project_uuid}_column_map")
+        ),
+        [system_name],
+    )
+    if len(exists) > 0:
+        return bool(exists[0][0])
+    else:
+        raise Exception("Error while checking whether system exists.")

backend/zeno_backend/routers/sdk.py

@@ -19,7 +19,7 @@
 
 from zeno_backend.classes.amplitude import AmplitudeHandler
 from zeno_backend.classes.project import Project
-from zeno_backend.database import insert, select, update
+from zeno_backend.database import delete, insert, select, update
 
 # MUST reflect views in frontend/src/lib/components/instance-views/views/viewMap.ts
 VIEWS = [
@@ -223,6 +223,10 @@ def upload_system(
             detail=("ERROR: Unable to read system data: " + str(e)),
         ) from e
 
+    # If a system with the same name already exists for the project, delete it.
+    if select.system_exists(project, system_name):
+        delete.system(project, system_name)
+
     try:
         insert.system(project, system_df, system_name, output_column, id_column)
     except Exception as e: