Fix previous version detection in the presence of inferred DDL migrations

pkg/roll/execute_test.go

@@ -62,43 +62,95 @@ func TestSchemaIsCreatedfterMigrationStart(t *testing.T) {
 func TestPreviousVersionIsDroppedAfterMigrationCompletion(t *testing.T) {
 	t.Parallel()
 
-	withMigratorAndConnectionToContainer(t, func(mig *roll.Roll, db *sql.DB) {
-		ctx := context.Background()
-		const (
-			firstVersion  = "1_create_table"
-			secondVersion = "2_create_table"
-		)
+	t.Run("when the previous version is a pgroll migration", func(t *testing.T) {
+		withMigratorAndConnectionToContainer(t, func(mig *roll.Roll, db *sql.DB) {
+			ctx := context.Background()
+			const (
+				firstVersion  = "1_create_table"
+				secondVersion = "2_create_table"
+			)
+
+			if err := mig.Start(ctx, &migrations.Migration{Name: firstVersion, Operations: migrations.Operations{createTableOp("table1")}}); err != nil {
+				t.Fatalf("Failed to start first migration: %v", err)
+			}
+			if err := mig.Complete(ctx); err != nil {
+				t.Fatalf("Failed to complete first migration: %v", err)
+			}
+			if err := mig.Start(ctx, &migrations.Migration{Name: secondVersion, Operations: migrations.Operations{createTableOp("table2")}}); err != nil {
+				t.Fatalf("Failed to start second migration: %v", err)
+			}
+			if err := mig.Complete(ctx); err != nil {
+				t.Fatalf("Failed to complete second migration: %v", err)
+			}
 
-		if err := mig.Start(ctx, &migrations.Migration{Name: firstVersion, Operations: migrations.Operations{createTableOp("table1")}}); err != nil {
-			t.Fatalf("Failed to start first migration: %v", err)
-		}
-		if err := mig.Complete(ctx); err != nil {
-			t.Fatalf("Failed to complete first migration: %v", err)
-		}
-		if err := mig.Start(ctx, &migrations.Migration{Name: secondVersion, Operations: migrations.Operations{createTableOp("table2")}}); err != nil {
-			t.Fatalf("Failed to start second migration: %v", err)
-		}
-		if err := mig.Complete(ctx); err != nil {
-			t.Fatalf("Failed to complete second migration: %v", err)
-		}
+			//
+			// Check that the schema for the first version has been dropped
+			//
+			var exists bool
+			err := db.QueryRow(`
+    SELECT EXISTS(
+      SELECT 1
+      FROM pg_catalog.pg_namespace
+      WHERE nspname = $1
+    )`, roll.VersionedSchemaName(schema, firstVersion)).Scan(&exists)
+			if err != nil {
+				t.Fatal(err)
+			}
 
-		//
-		// Check that the schema for the first version has been dropped
-		//
-		var exists bool
-		err := db.QueryRow(`
+			if exists {
+				t.Errorf("Expected schema %q to not exist", firstVersion)
+			}
+		})
+	})
+
+	t.Run("when the previous version is an inferred DDL migration", func(t *testing.T) {
+		withMigratorAndConnectionToContainer(t, func(mig *roll.Roll, db *sql.DB) {
+			ctx := context.Background()
+			const (
+				firstVersion  = "1_create_table"
+				secondVersion = "2_create_table"
+			)
+
+			// Run the first pgroll migration
+			if err := mig.Start(ctx, &migrations.Migration{Name: firstVersion, Operations: migrations.Operations{createTableOp("table1")}}); err != nil {
+				t.Fatalf("Failed to start first migration: %v", err)
+			}
+			if err := mig.Complete(ctx); err != nil {
+				t.Fatalf("Failed to complete first migration: %v", err)
+			}
+
+			// Run a manual DDL migration
+			_, err := db.ExecContext(ctx, "CREATE TABLE foo (id integer)")
+			if err != nil {
+				t.Fatalf("Failed to create table: %v", err)
+			}
+
+			// Run the second pgroll migration
+			if err := mig.Start(ctx, &migrations.Migration{Name: secondVersion, Operations: migrations.Operations{createTableOp("table2")}}); err != nil {
+				t.Fatalf("Failed to start second migration: %v", err)
+			}
+			if err := mig.Complete(ctx); err != nil {
+				t.Fatalf("Failed to complete second migration: %v", err)
+			}
+
+			//
+			// Check that the schema for the first version has been dropped
+			//
+			var exists bool
+			err = db.QueryRow(`
     SELECT EXISTS(
       SELECT 1
       FROM pg_catalog.pg_namespace
       WHERE nspname = $1
     )`, roll.VersionedSchemaName(schema, firstVersion)).Scan(&exists)
-		if err != nil {
-			t.Fatal(err)
-		}
+			if err != nil {
+				t.Fatal(err)
+			}
 
-		if exists {
-			t.Errorf("Expected schema %q to not exist", firstVersion)
-		}
+			if exists {
+				t.Errorf("Expected schema %q to not exist", firstVersion)
+			}
+		})
 	})
 }
 

pkg/state/state.go

@@ -41,6 +41,13 @@ CREATE UNIQUE INDEX IF NOT EXISTS only_first_migration_without_parent ON %[1]s.m
 -- History is linear
 CREATE UNIQUE INDEX IF NOT EXISTS history_is_linear ON %[1]s.migrations (schema, parent);
 
+-- Add a column to tell whether the row represents an auto-detected DDL capture or a pgroll migration
+ALTER TABLE %[1]s.migrations ADD COLUMN IF NOT EXISTS migration_type
+  VARCHAR(32)
+  DEFAULT 'pgroll'
+  CONSTRAINT migration_type_check CHECK (migration_type IN ('pgroll', 'inferred')
+);
+
 -- Helper functions
 
 -- Are we in the middle of a migration?
@@ -65,7 +72,20 @@ STABLE;
 -- Get the name of the previous version of the schema, or NULL if there is none.
 CREATE OR REPLACE FUNCTION %[1]s.previous_version(schemaname NAME) RETURNS text
 AS $$
-  SELECT parent FROM %[1]s.migrations WHERE name = (SELECT %[1]s.latest_version(schemaname)) AND schema=schemaname;
+  WITH RECURSIVE find_ancestor AS (
+    SELECT schema, name, parent, migration_type FROM pgroll.migrations 
+      WHERE name = (SELECT %[1]s.latest_version(schemaname)) AND schema = schemaname
+
+    UNION ALL
+
+    SELECT m.schema, m.name, m.parent, m.migration_type FROM pgroll.migrations m
+      INNER JOIN find_ancestor fa ON fa.parent = m.name AND fa.schema = m.schema
+      WHERE m.migration_type = 'inferred'
+  )
+  SELECT a.parent
+  FROM find_ancestor AS a
+  JOIN pgroll.migrations AS b ON a.parent = b.name AND a.schema = b.schema
+  WHERE b.migration_type = 'pgroll';
 $$
 LANGUAGE SQL
 STABLE;
@@ -192,14 +212,15 @@ BEGIN
 	END IF;
 
 	-- Someone did a schema change without pgroll, include it in the history
-	INSERT INTO %[1]s.migrations (schema, name, migration, resulting_schema, done, parent)
+	INSERT INTO %[1]s.migrations (schema, name, migration, resulting_schema, done, parent, migration_type)
 	VALUES (
 		schemaname,
 		pg_catalog.format('sql_%%s',pg_catalog.substr(pg_catalog.md5(pg_catalog.random()::text), 0, 15)),
 		pg_catalog.json_build_object('sql', pg_catalog.json_build_object('up', pg_catalog.current_query())),
 		%[1]s.read_schema(schemaname),
 		true,
-		%[1]s.latest_version(schemaname)
+		%[1]s.latest_version(schemaname),
+		'inferred'
 	);
 END;
 $$;