Add db fallback mode

README.md

@@ -66,6 +66,17 @@ Multiple aliases may be supported on a single host.
       action [:setup, :start]
     end
 
+    # setup and start a connection pool with database fallback (all databases)
+    pgbouncer_connection "database_example_com_fallback" do
+      db_host "database.example.com"
+      db_port "6432"
+      use_db_fallback true
+      userlist "readwrite_user" => "md500000000000000000000000000000000", "readonly_user" => "md500000000000000000000000000000000"
+      max_client_conn 100
+      default_pool_size 20
+      action [:setup, :start]
+    end
+
     # stop a connection pool
     pgbouncer_connection "database_example_com_ro" do
       action :stop

resources/connection.rb

@@ -23,7 +23,9 @@
 attribute :db_alias, :kind_of => String, :name_attribute => true
 attribute :db_host, :kind_of => String, :required => true
 attribute :db_port, :kind_of => String, :required => true
-attribute :db_name, :kind_of => String, :required => true
+attribute :db_name, :kind_of => String
+
+attribute :use_db_fallback, :kind_of => [TrueClass, FalseClass], :default => false
 
 attribute :userlist, :kind_of => Hash, :required => true
 

templates/default/etc/pgbouncer/pgbouncer.ini.erb

@@ -5,7 +5,11 @@
 ;;   client_encoding= datestyle= timezone=
 ;;   pool_size= connect_query=
 [databases]
+<% if @use_db_fallback %>
+* = host=<%= @db_host %> port=<%= @db_port %>
+<% else %>
 <%= @db_alias %> = host=<%= @db_host %> port=<%= @db_port %> dbname=<%= @db_name %> <%= "connect_query='#{@connect_query}'" unless @connect_query.nil? || @connect_query.empty? %>
+<% end %>
 
 ;; Configuration section
 [pgbouncer]