User following mechanics

migrations/versions/7d51bc4b6079_.py

@@ -0,0 +1,31 @@
+"""Add user_followers table
+
+Revision ID: 7d51bc4b6079
+Revises: 4aa88f253dab
+Create Date: 2023-01-17 12:48:33.261942
+
+"""
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision = '7d51bc4b6079'
+down_revision = '4aa88f253dab'
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+    op.create_table(
+        'user_followers',
+        sa.Column('follower_user_id', sa.Integer(), nullable=False),
+        sa.Column('followed_user_id', sa.Integer(), nullable=False),
+        sa.ForeignKeyConstraint(['followed_user_id'], ['users.id'], ),
+        sa.ForeignKeyConstraint(['follower_user_id'], ['users.id'], ),
+        sa.PrimaryKeyConstraint('follower_user_id', 'followed_user_id')
+    )
+
+
+def downgrade():
+    op.drop_table('user_followers')