WIP checkpoint: Friends/follow/block models + Alembic migration

2026-08-18 15:50:36 +00:00
parent a9947a0a80
commit ca06b459ec
7 changed files with 348 additions and 2 deletions
@@ -0,0 +1,126 @@
+"""social graph: friendships, follows, blocks
+
+Revision ID: 0002_social_graph
+Revises: 0001_initial
+Create Date: 2026-08-18 00:00:00.000000
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+
+# revision identifiers, used by Alembic.
+revision: str = "0002_social_graph"
+down_revision: Union[str, None] = "0001_initial"
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    """Create friendships, follows, and blocks tables."""
+    op.create_table(
+        "friendships",
+        sa.Column("id", sa.Integer(), nullable=False),
+        sa.Column("requester_id", sa.Integer(), nullable=False),
+        sa.Column("addressee_id", sa.Integer(), nullable=False),
+        sa.Column("status", sa.String(length=20), nullable=False),
+        sa.Column("created_at", sa.DateTime(timezone=True), server_default=sa.func.now(), nullable=False),
+        sa.Column("updated_at", sa.DateTime(timezone=True), nullable=True),
+        sa.CheckConstraint(
+            "status IN ('pending', 'accepted')",
+            name="ck_friendships_status",
+        ),
+        sa.CheckConstraint(
+            "requester_id <> addressee_id",
+            name="ck_friendships_no_self",
+        ),
+        sa.ForeignKeyConstraint(
+            ["addressee_id"],
+            ["users.id"],
+            ondelete="CASCADE",
+        ),
+        sa.ForeignKeyConstraint(
+            ["requester_id"],
+            ["users.id"],
+            ondelete="CASCADE",
+        ),
+        sa.PrimaryKeyConstraint("id"),
+        sa.UniqueConstraint(
+            "requester_id",
+            "addressee_id",
+            name="uq_friendships_pair",
+        ),
+    )
+    op.create_index(op.f("ix_friendships_id"), "friendships", ["id"], unique=False)
+    op.create_index(op.f("ix_friendships_addressee_id"), "friendships", ["addressee_id"], unique=False)
+    op.create_index(op.f("ix_friendships_requester_id"), "friendships", ["requester_id"], unique=False)
+
+    op.create_table(
+        "follows",
+        sa.Column("follower_id", sa.Integer(), nullable=False),
+        sa.Column("followed_id", sa.Integer(), nullable=False),
+        sa.Column("created_at", sa.DateTime(timezone=True), server_default=sa.func.now(), nullable=False),
+        sa.CheckConstraint(
+            "follower_id <> followed_id",
+            name="ck_follows_no_self",
+        ),
+        sa.ForeignKeyConstraint(
+            ["followed_id"],
+            ["users.id"],
+            ondelete="CASCADE",
+        ),
+        sa.ForeignKeyConstraint(
+            ["follower_id"],
+            ["users.id"],
+            ondelete="CASCADE",
+        ),
+        sa.PrimaryKeyConstraint("follower_id", "followed_id"),
+        sa.UniqueConstraint(
+            "follower_id",
+            "followed_id",
+            name="uq_follows_pair",
+        ),
+    )
+    op.create_index(op.f("ix_follows_followed_id"), "follows", ["followed_id"], unique=False)
+
+    op.create_table(
+        "blocks",
+        sa.Column("blocker_id", sa.Integer(), nullable=False),
+        sa.Column("blocked_id", sa.Integer(), nullable=False),
+        sa.Column("created_at", sa.DateTime(timezone=True), server_default=sa.func.now(), nullable=False),
+        sa.CheckConstraint(
+            "blocker_id <> blocked_id",
+            name="ck_blocks_no_self",
+        ),
+        sa.ForeignKeyConstraint(
+            ["blocked_id"],
+            ["users.id"],
+            ondelete="CASCADE",
+        ),
+        sa.ForeignKeyConstraint(
+            ["blocker_id"],
+            ["users.id"],
+            ondelete="CASCADE",
+        ),
+        sa.PrimaryKeyConstraint("blocker_id", "blocked_id"),
+        sa.UniqueConstraint(
+            "blocker_id",
+            "blocked_id",
+            name="uq_blocks_pair",
+        ),
+    )
+    op.create_index(op.f("ix_blocks_blocked_id"), "blocks", ["blocked_id"], unique=False)
+
+
+def downgrade() -> None:
+    """Drop friendships, follows, and blocks tables."""
+    op.drop_index(op.f("ix_blocks_blocked_id"), table_name="blocks")
+    op.drop_table("blocks")
+
+    op.drop_index(op.f("ix_follows_followed_id"), table_name="follows")
+    op.drop_table("follows")
+
+    op.drop_index(op.f("ix_friendships_requester_id"), table_name="friendships")
+    op.drop_index(op.f("ix_friendships_addressee_id"), table_name="friendships")
+    op.drop_index(op.f("ix_friendships_id"), table_name="friendships")
+    op.drop_table("friendships")