migrations

# Butterbase App Migrations (Multi-Region) Moving an app between regions is an orchestrated migration: data dumped from source, restored in dest, blobs copied, runtime brought up, then traffic flipped. Source replica is retained for safe rollback until you tear it down. Four small tools wrap the orchestration: | Tool | Purpose | |---|---| | `list_regions` | Discover what regions exist before suggesting one. | | `move_app` | Start a migration. Returns a `migration_id`. | | `move_app_status` | Read the current step + replica state of a specific migration. | | `manage_migrations` | Operational ops: `get_active`, `abort`, `reverse`, `list_source_replicas`. | | `teardown_source_replica` | Decommission the retained source replica once you're confident. | --- ## 1. The step sequence A successful move walks through 11 steps in order: ``` requested → reserving_dest → blocking_writes → dumping_data → restoring_data → copying_blobs → copying_runtime → flipping_routing → setting_up_reverse_replication → unblocking_writes → completed ``` The cutover happens at `flipping_routing`. Before that, the app is still served from the source. After that, traffic is on the destination. Terminal states: `completed`, `aborted`, `failed`. --- ## 2. Start a move ``` list_regions → confirm dest region is supported move_app(app_id, dest_region) → { migration_id, status: "queued" } ``` Then poll with `move_app_status({ app_id, migration_id })` every few seconds (or call `manage_mi...