Allow a list of schemas when switching using schemas

README.md

@@ -89,6 +89,14 @@ would not allow a full new database to be created.
 
 One can optionally use the full database creation instead if they want, though this is not recommended
 
+When using schemas, you can also pass in a list of schemas if desired. Any tables defined in a schema earlier in the chain will be referenced first, so this is only useful if you have a schema with only some of the tables defined:
+
+```ruby
+Apartment::Tenant.switch(['tenant_1', 'tenant_2']) do
+  # ...
+end
+```
+
 ### Switching Tenants
 
 To switch tenants using Apartment, use the following command:

lib/apartment/adapters/postgresql_adapter.rb

@@ -63,9 +63,9 @@ def drop_command(conn, tenant)
       #
       def connect_to_new(tenant = nil)
         return reset if tenant.nil?
-        raise ActiveRecord::StatementInvalid.new("Could not find schema #{tenant}") unless Apartment.connection.schema_exists?(tenant.to_s)
+        raise ActiveRecord::StatementInvalid.new("Could not find schema #{tenant}") unless schema_exists?(tenant)
 
-        @current = tenant.to_s
+        @current = tenant.is_a?(Array) ? tenant.map(&:to_s) : tenant.to_s
         Apartment.connection.schema_search_path = full_search_path
 
         # When the PostgreSQL version is < 9.3,
@@ -100,6 +100,10 @@ def postgresql_version
         # public from Rails 5.0.
         Apartment.connection.send(:postgresql_version)
       end
+
+      def schema_exists?(schemas)
+        [*schemas].all? { |schema| Apartment.connection.schema_exists?(schema.to_s) }
+      end
     end
 
     # Another Adapter for Postgresql when using schemas and SQL

spec/examples/schema_adapter_examples.rb

@@ -122,6 +122,13 @@
 
       expect(connection.schema_search_path).to start_with %{"#{public_schema}"}
     end
+
+    it "allows a list of schemas" do
+      subject.switch([schema1, schema2]) do
+        expect(connection.schema_search_path).to include %{"#{schema1}"}
+        expect(connection.schema_search_path).to include %{"#{schema2}"}
+      end
+    end
   end
 
   describe "#reset" do