Allow rails to be initialized without connecting to the database

README.md

@@ -594,6 +594,17 @@ module Apartment
 end
 ```
 
+## Running rails console without a connection
+
+Before this fork, running rails with the gem installed would connect to the database
+which is different than the default behavior. To disable this initial
+connection, just run with `APARTMENT_DISABLE_INIT` set to something:
+
+```shell
+$ APARTMENT_DISABLE_INIT=true DATABASE_URL=postgresql://localhost:1234/buk_development bin/rails runner 'puts 1'
+# 1
+```
+
 ## Contributing
 
 * In both `spec/dummy/config` and `spec/config`, you will see `database.yml.sample` files

lib/apartment/railtie.rb

@@ -33,6 +33,7 @@ class Railtie < Rails::Railtie
     config.to_prepare do
       next if ARGV.any? { |arg| arg =~ /\Aassets:(?:precompile|clean)\z/ }
       next if ARGV.any? { |arg| arg == 'webpacker:compile' }
+      next if ENV["APARTMENT_DISABLE_INIT"]
 
       begin
         Apartment.connection_class.connection_pool.with_connection do

spec/examples/generic_adapter_examples.rb

@@ -24,6 +24,24 @@
 
       expect(num_available_connections).to eq(1)
     end
+
+    it 'should not connect if env var is set' do
+      ENV["APARTMENT_DISABLE_INIT"] = "true"
+      begin
+        ActiveRecord::Base.connection_pool.disconnect!
+
+        Apartment::Railtie.config.to_prepare_blocks.map(&:call)
+
+        num_available_connections = Apartment.connection_class.connection_pool
+          .instance_variable_get(:@available)
+          .instance_variable_get(:@queue)
+          .size
+
+        expect(num_available_connections).to eq(0)
+      ensure
+        ENV.delete("APARTMENT_DISABLE_INIT")
+      end
+    end
   end
 
   #