fixed migrations

migrations/versions/add_conversations_tables.py

@@ -7,6 +7,7 @@ Create Date: 2024-03-19 10:00:00.000000
 """
 from alembic import op
 import sqlalchemy as sa
+from sqlalchemy import inspect
 
 
 # revision identifiers, used by Alembic.
@@ -18,7 +19,12 @@ depends_on = None
 
 def upgrade():
     # Create conversation table first
-    op.create_table('conversation',
+        conn = op.get_bind()
+    inspector = inspect(conn)
+    tables = inspector.get_table_names()
+    
+    if 'conversation' not in tables:
+        op.create_table('conversation',
         sa.Column('id', sa.Integer(), nullable=False),
         sa.Column('name', sa.String(length=100), nullable=False),
         sa.Column('description', sa.Text(), nullable=True),
@@ -29,7 +35,12 @@ def upgrade():
     )
 
     # Create conversation_members table
-    op.create_table('conversation_members',
+        conn = op.get_bind()
+    inspector = inspect(conn)
+    tables = inspector.get_table_names()
+    
+    if 'conversation_members' not in tables:
+        op.create_table('conversation_members',
         sa.Column('conversation_id', sa.Integer(), nullable=False),
         sa.Column('user_id', sa.Integer(), nullable=False),
         sa.ForeignKeyConstraint(['conversation_id'], ['conversation.id'], ),
@@ -38,7 +49,12 @@ def upgrade():
     )
 
     # Create message table
-    op.create_table('message',
+        conn = op.get_bind()
+    inspector = inspect(conn)
+    tables = inspector.get_table_names()
+    
+    if 'message' not in tables:
+        op.create_table('message',
         sa.Column('id', sa.Integer(), nullable=False),
         sa.Column('content', sa.Text(), nullable=False),
         sa.Column('created_at', sa.DateTime(), nullable=True),