US06-02: Transfer, Verify, and Remove Active Sources (#78)

migrations/versions/0012_archive_plans.py

@@ -0,0 +1,96 @@
+"""Archive plans, per-item transfer journal, and archived asset location (US06-02).
+
+Revision ID: 0012_archive_plans
+Revises: 0011_archive_locations
+Create Date: 2026-08-16
+
+The journal is what makes removing an original recoverable: every item records its
+source, destination, expected hash, and the state it had reached before the process
+died. Assets gain the archive location and relative path so an offline original is
+still explained rather than looking missing.
+"""
+
+import sqlalchemy as sa
+from alembic import op
+
+revision = "0012_archive_plans"
+down_revision = "0011_archive_locations"
+branch_labels = None
+depends_on = None
+
+
+def upgrade() -> None:
+    op.create_table(
+        "archive_plans",
+        sa.Column("id", sa.String(), primary_key=True),
+        sa.Column(
+            "location_id",
+            sa.String(),
+            sa.ForeignKey("archive_locations.id"),
+            nullable=False,
+            index=True,
+        ),
+        # The preflight token this plan was approved against.
+        sa.Column("token", sa.String(), nullable=False),
+        sa.Column("albums", sa.String(), nullable=True),  # JSON array
+        # planned | applying | complete | failed
+        sa.Column("state", sa.String(), nullable=False, server_default="planned"),
+        sa.Column("schema_version", sa.Integer(), nullable=False, server_default="1"),
+        sa.Column("asset_count", sa.Integer(), nullable=False, server_default="0"),
+        sa.Column("byte_size", sa.Integer(), nullable=False, server_default="0"),
+        # Bumped on every claim and used as the fencing token.
+        sa.Column("version", sa.Integer(), nullable=False, server_default="1"),
+        sa.Column("worker_id", sa.String(), nullable=True),
+        sa.Column("completed_at", sa.DateTime(timezone=True), nullable=True),
+        sa.Column(
+            "created_at", sa.DateTime(timezone=True), nullable=False, server_default=sa.func.now()
+        ),
+        sa.Column(
+            "updated_at", sa.DateTime(timezone=True), nullable=False, server_default=sa.func.now()
+        ),
+    )
+    op.create_table(
+        "archive_operations",
+        sa.Column("id", sa.String(), primary_key=True),
+        sa.Column(
+            "plan_id",
+            sa.String(),
+            sa.ForeignKey("archive_plans.id", ondelete="CASCADE"),
+            nullable=False,
+            index=True,
+        ),
+        sa.Column("sequence", sa.Integer(), nullable=False),
+        sa.Column("album", sa.String(), nullable=False),
+        sa.Column("asset_id", sa.String(), sa.ForeignKey("assets.id"), nullable=False, index=True),
+        sa.Column("source_path", sa.String(), nullable=False),
+        sa.Column("destination_path", sa.String(), nullable=False),
+        # Relative to the location root: the medium can be mounted anywhere later.
+        sa.Column("archive_path", sa.String(), nullable=False),
+        sa.Column("expected_sha256", sa.String(), nullable=False),
+        sa.Column("byte_size", sa.Integer(), nullable=True),
+        sa.Column("same_filesystem", sa.Boolean(), nullable=True),
+        # planned | transferring | verified | removing | complete | failed
+        sa.Column("journal_state", sa.String(), nullable=False, server_default="planned"),
+        sa.Column("attempt_count", sa.Integer(), nullable=False, server_default="0"),
+        sa.Column("fencing_token", sa.Integer(), nullable=True),
+        sa.Column("worker_id", sa.String(), nullable=True),
+        sa.Column("verified_at", sa.DateTime(timezone=True), nullable=True),
+        sa.Column("removed_at", sa.DateTime(timezone=True), nullable=True),
+        sa.Column("error_code", sa.String(), nullable=True),
+        sa.Column("error_message", sa.String(), nullable=True),
+        sa.Column(
+            "updated_at", sa.DateTime(timezone=True), nullable=False, server_default=sa.func.now()
+        ),
+        sa.UniqueConstraint("plan_id", "sequence", name="uq_archive_operations_plan_sequence"),
+    )
+    # Plain columns: SQLite cannot ALTER a table to add a foreign key, and the
+    # relationship is enforced by the service that writes them.
+    op.add_column("assets", sa.Column("archive_location_id", sa.String(), nullable=True))
+    op.add_column("assets", sa.Column("archive_path", sa.String(), nullable=True))
+
+
+def downgrade() -> None:
+    op.drop_column("assets", "archive_path")
+    op.drop_column("assets", "archive_location_id")
+    op.drop_table("archive_operations")
+    op.drop_table("archive_plans")