Namespace user API tables (#2806)

This migrates all the various user API tables, indices and sequences to
be `userapi_`-namespaced, rather than the mess they are all now.

userapi/storage/postgres/deltas/2022101711000000_rename_tables.go

@@ -0,0 +1,102 @@
+package deltas
+
+import (
+	"context"
+	"database/sql"
+	"fmt"
+
+	"github.com/lib/pq"
+)
+
+var renameTableMappings = map[string]string{
+	"account_accounts":               "userapi_accounts",
+	"account_data":                   "userapi_account_datas",
+	"device_devices":                 "userapi_devices",
+	"account_e2e_room_keys":          "userapi_key_backups",
+	"account_e2e_room_keys_versions": "userapi_key_backup_versions",
+	"login_tokens":                   "userapi_login_tokens",
+	"open_id_tokens":                 "userapi_openid_tokens",
+	"account_profiles":               "userapi_profiles",
+	"account_threepid":               "userapi_threepids",
+}
+
+var renameSequenceMappings = map[string]string{
+	"device_session_id_seq":              "userapi_device_session_id_seq",
+	"account_e2e_room_keys_versions_seq": "userapi_key_backup_versions_seq",
+}
+
+var renameIndicesMappings = map[string]string{
+	"device_localpart_id_idx":            "userapi_device_localpart_id_idx",
+	"e2e_room_keys_idx":                  "userapi_key_backups_idx",
+	"e2e_room_keys_versions_idx":         "userapi_key_backups_versions_idx",
+	"account_e2e_room_keys_versions_idx": "userapi_key_backup_versions_idx",
+	"login_tokens_expiration_idx":        "userapi_login_tokens_expiration_idx",
+	"account_threepid_localpart":         "userapi_threepid_idx",
+}
+
+// I know what you're thinking: you're wondering "why doesn't this use $1
+// and pass variadic parameters to ExecContext?" — the answer is because
+// PostgreSQL doesn't expect the table name to be specified as a substituted
+// argument in that way so it results in a syntax error in the query.
+
+func UpRenameTables(ctx context.Context, tx *sql.Tx) error {
+	for old, new := range renameTableMappings {
+		q := fmt.Sprintf(
+			"ALTER TABLE IF EXISTS %s RENAME TO %s;",
+			pq.QuoteIdentifier(old), pq.QuoteIdentifier(new),
+		)
+		if _, err := tx.ExecContext(ctx, q); err != nil {
+			return fmt.Errorf("rename table %q to %q error: %w", old, new, err)
+		}
+	}
+	for old, new := range renameSequenceMappings {
+		q := fmt.Sprintf(
+			"ALTER SEQUENCE IF EXISTS %s RENAME TO %s;",
+			pq.QuoteIdentifier(old), pq.QuoteIdentifier(new),
+		)
+		if _, err := tx.ExecContext(ctx, q); err != nil {
+			return fmt.Errorf("rename table %q to %q error: %w", old, new, err)
+		}
+	}
+	for old, new := range renameIndicesMappings {
+		q := fmt.Sprintf(
+			"ALTER INDEX IF EXISTS %s RENAME TO %s;",
+			pq.QuoteIdentifier(old), pq.QuoteIdentifier(new),
+		)
+		if _, err := tx.ExecContext(ctx, q); err != nil {
+			return fmt.Errorf("rename table %q to %q error: %w", old, new, err)
+		}
+	}
+	return nil
+}
+
+func DownRenameTables(ctx context.Context, tx *sql.Tx) error {
+	for old, new := range renameTableMappings {
+		q := fmt.Sprintf(
+			"ALTER TABLE IF EXISTS %s RENAME TO %s;",
+			pq.QuoteIdentifier(new), pq.QuoteIdentifier(old),
+		)
+		if _, err := tx.ExecContext(ctx, q); err != nil {
+			return fmt.Errorf("rename table %q to %q error: %w", new, old, err)
+		}
+	}
+	for old, new := range renameSequenceMappings {
+		q := fmt.Sprintf(
+			"ALTER SEQUENCE IF EXISTS %s RENAME TO %s;",
+			pq.QuoteIdentifier(new), pq.QuoteIdentifier(old),
+		)
+		if _, err := tx.ExecContext(ctx, q); err != nil {
+			return fmt.Errorf("rename table %q to %q error: %w", new, old, err)
+		}
+	}
+	for old, new := range renameIndicesMappings {
+		q := fmt.Sprintf(
+			"ALTER INDEX IF EXISTS %s RENAME TO %s;",
+			pq.QuoteIdentifier(new), pq.QuoteIdentifier(old),
+		)
+		if _, err := tx.ExecContext(ctx, q); err != nil {
+			return fmt.Errorf("rename table %q to %q error: %w", new, old, err)
+		}
+	}
+	return nil
+}