Add support for new pgbouncer settings

Adds support for:
* max_prepared_statements,
* track_extra_parameters,
* auth_dbname,
* cancel_wait_timeout,
* so_reuseport, and
* the peers section.

pgbouncer docs: https://www.pgbouncer.org/config.html

Changelog: added

Author: Clemens Beck

files/gitlab-config-template/gitlab.rb.template

@@ -3026,6 +3026,7 @@ external_url 'GENERATED_EXTERNAL_URL'
 # pgbouncer['listen_addr'] = '0.0.0.0'
 # pgbouncer['listen_port'] = '6432'
 # pgbouncer['pool_mode'] = 'transaction'
+# pgbouncer['max_prepared_statements'] = 0
 # pgbouncer['server_reset_query'] = 'DISCARD ALL'
 # pgbouncer['application_name_add_host'] = '1'
 # pgbouncer['max_client_conn'] = '2048'
@@ -3042,6 +3043,7 @@ external_url 'GENERATED_EXTERNAL_URL'
 # pgbouncer['admin_users'] = %w(gitlab-psql postgres pgbouncer)
 # pgbouncer['stats_users'] = %w(gitlab-psql postgres pgbouncer)
 # pgbouncer['ignore_startup_parameters'] = 'extra_float_digits'
+# pgbouncer['track_extra_parameters'] = %w(IntervalStyle)
 # pgbouncer['databases'] = {
 #   DATABASE_NAME: {
 #     host: HOSTNAME,
@@ -3058,6 +3060,7 @@ external_url 'GENERATED_EXTERNAL_URL'
 # pgbouncer['unix_socket_group'] = nil
 # pgbouncer['auth_type'] = 'md5'
 # pgbouncer['auth_hba_file'] = nil
+# pgbouncer['auth_dbname'] = nil
 # pgbouncer['auth_query'] = 'SELECT username, password FROM public.pg_shadow_lookup($1)'
 # pgbouncer['users'] = {
 #   USERNAME: {
@@ -3088,17 +3091,20 @@ external_url 'GENERATED_EXTERNAL_URL'
 # pgbouncer['autodb_idle_timeout'] = 3600
 # pgbouncer['suspend_timeout'] = 10
 # pgbouncer['idle_transaction_timeout'] = 0
+# pgbouncer['cancel_wait_timeout'] = 10
 # pgbouncer['pkt_buf'] = 4096
 # pgbouncer['listen_backlog'] = 128
 # pgbouncer['sbuf_loopcnt'] = 5
 # pgbouncer['max_packet_size'] = 2147483647
+# pgbouncer['so_reuseport'] = 0
 # pgbouncer['tcp_defer_accept'] = 0
 # pgbouncer['tcp_socket_buffer'] = 0
 # pgbouncer['tcp_keepalive'] = 1
 # pgbouncer['tcp_keepcnt'] = 0
 # pgbouncer['tcp_keepidle'] = 0
 # pgbouncer['tcp_keepintvl'] = 0
 # pgbouncer['disable_pqexec'] = 0
+# default['pgbouncer']['peers'] = {}
 
 ## Pgbouncer client TLS options
 # pgbouncer['client_tls_sslmode'] = 'disable'

files/gitlab-cookbooks/pgbouncer/attributes/default.rb

@@ -8,6 +8,7 @@
 default['pgbouncer']['listen_addr'] = '0.0.0.0'
 default['pgbouncer']['listen_port'] = 6432
 default['pgbouncer']['pool_mode'] = 'transaction'
+default['pgbouncer']['max_prepared_statements'] = 0
 default['pgbouncer']['server_reset_query'] = 'DISCARD ALL'
 default['pgbouncer']['max_client_conn'] = 2048
 default['pgbouncer']['application_name_add_host'] = 1
@@ -24,6 +25,7 @@
 default['pgbouncer']['admin_users'] = %w(gitlab-psql postgres pgbouncer)
 default['pgbouncer']['stats_users'] = %w(gitlab-psql postgres pgbouncer)
 default['pgbouncer']['ignore_startup_parameters'] = 'extra_float_digits'
+default['pgbouncer']['track_extra_parameters'] = %w(IntervalStyle)
 default['pgbouncer']['databases_ini'] = '/var/opt/gitlab/pgbouncer/databases.ini'
 default['pgbouncer']['databases_ini_user'] = 'root'
 default['pgbouncer']['databases_json'] = '/var/opt/gitlab/pgbouncer/databases.json'
@@ -68,20 +70,24 @@
 default['pgbouncer']['autodb_idle_timeout'] = 3600
 default['pgbouncer']['suspend_timeout'] = 10
 default['pgbouncer']['idle_transaction_timeout'] = 0
+default['pgbouncer']['cancel_wait_timeout'] = 10
 default['pgbouncer']['pkt_buf'] = 4096
 default['pgbouncer']['listen_backlog'] = 128
 default['pgbouncer']['sbuf_loopcnt'] = 5
 default['pgbouncer']['max_packet_size'] = 2147483647
+default['pgbouncer']['so_reuseport'] = 0
 default['pgbouncer']['tcp_defer_accept'] = 0
 default['pgbouncer']['tcp_socket_buffer'] = 0
 default['pgbouncer']['tcp_keepalive'] = 1
 default['pgbouncer']['tcp_keepcnt'] = 0
 default['pgbouncer']['tcp_keepidle'] = 0
 default['pgbouncer']['tcp_keepintvl'] = 0
 default['pgbouncer']['disable_pqexec'] = 0
+default['pgbouncer']['peers'] = {}
 
 default['pgbouncer']['auth_type'] = 'md5'
 default['pgbouncer']['auth_hba_file'] = nil
+default['pgbouncer']['auth_dbname'] = nil
 default['pgbouncer']['auth_query'] = 'SELECT username, password FROM public.pg_shadow_lookup($1)'
 default['pgbouncer']['users'] = {}
 

files/gitlab-cookbooks/pgbouncer/templates/default/peers.ini.erb

@@ -123,6 +123,12 @@ auth_hba_file = <%= @auth_hba_file %>
 ;; Query to use to fetch password from database.  Result
 ;; must have 2 columns - username and password hash.
 auth_query = <%= @auth_query %>
+
+<% if @auth_dbname %>
+; Authentication database that can be set globally to run "auth_query".
+auth_dbname = <%= @auth_dbname %>
+<% end %>
+
 ;;;
 ;;; Users allowed into database 'pgbouncer'
 ;;;
@@ -143,6 +149,10 @@ stats_users = <%= @stats_users.join(', ') %>
 ;   statement    - after statement finishes
 pool_mode = <%= @pool_mode %>
 
+; Number of prepared statements to cache on a server connection (zero value
+; disables support of prepared statements).
+max_prepared_statements = <%= @max_prepared_statements %>
+
 ;
 ; Query for cleaning connection immediately after releasing from client.
 ; No need to put ROLLBACK here, pgbouncer does not reuse connections
@@ -163,6 +173,11 @@ server_reset_query = <%= @server_reset_query %>
 ; If it is off, server_reset_query is used only for session-pooling.
 server_reset_query_always = <%= @server_reset_query_always %>
 
+; Comma-separated list of parameters to track per client. The Postgres 
+; parameters listed here will be cached per client by pgbouncer and 
+; restored in server everytime the client runs a query. 
+track_extra_parameters = <%= @track_extra_parameters.join(', ') %>
+
 ;
 ; Comma-separated list of parameters to ignore when given
 ; in startup packet.  Newer JDBC versions require the
@@ -286,6 +301,12 @@ suspend_timeout = <%= @suspend_timeout %>
 ;; this many seconds.
 idle_transaction_timeout = <%= @idle_transaction_timeout %>
 
+;; Dangerous.  Client connection is closed if the cancellation request
+;; is not assigned to a server in this time.  Should be used to limit
+;; the time a client application blocks on a queued cancel request in
+;; case of a database or network failure. (default: 10)
+cancel_wait_timeout = <%= @cancel_wait_timeout %>
+
 ;;;
 ;;; Low-level tuning options
 ;;;
@@ -302,6 +323,9 @@ sbuf_loopcnt = <%= @sbuf_loopcnt %>
 ;; Maximum Postgres protocol packet size.
 max_packet_size = <%= @max_packet_size %>
 
+;; Set SO_REUSEPORT socket option
+so_reuseport = <%= @so_reuseport %>
+
 ;; networking options, for info: man 7 tcp
 
 ;; Linux: notify program about new connection only if there
@@ -354,6 +378,14 @@ disable_pqexec = <%= @disable_pqexec %>
 ;service_name = pgbouncer
 ;job_name = pgbouncer
 
+;;;
+;;; Peers
+;;;
+[peers]
+<% @peers.each do |peer_id, settings| %>
+<%= peer_id %> = <%= settings.map{ |k,v| "#{k}=#{v}" }.join(' ') %>
+<% end %>
+
 ;; Read additional config from the /etc/pgbouncer/pgbouncer-other.ini file
 ;%include /etc/pgbouncer/pgbouncer-other.ini
 %include <%= @databases_ini %>

files/gitlab-cookbooks/pgbouncer/templates/default/pgbouncer.ini.erb

@@ -72,6 +72,7 @@
         expect(content).to match(/^listen_addr = 0\.0\.0\.0$/)
         expect(content).to match(/^listen_port = 6432$/)
         expect(content).to match(/^pool_mode = transaction$/)
+        expect(content).to match(/^max_prepared_statements = 0$/)
         expect(content).to match(/^server_reset_query = DISCARD ALL$/)
         expect(content).to match(/^application_name_add_host = 1$/)
         expect(content).to match(/^max_client_conn = 2048$/)
@@ -90,6 +91,7 @@
         expect(content).to match(/^admin_users = gitlab-psql, postgres, pgbouncer$/)
         expect(content).to match(/^stats_users = gitlab-psql, postgres, pgbouncer$/)
         expect(content).to match(/^ignore_startup_parameters = extra_float_digits$/)
+        expect(content).to match(/^track_extra_parameters = IntervalStyle$/)
         expect(content).to match(%r{^unix_socket_dir = /var/opt/gitlab/pgbouncer$})
         expect(content).to match(%r{^%include /var/opt/gitlab/pgbouncer/databases.ini})
         expect(content).to match(/^unix_socket_mode = 0777$/)
@@ -120,10 +122,12 @@
         expect(content).to match(/^autodb_idle_timeout = 3600$/)
         expect(content).to match(/^suspend_timeout = 10$/)
         expect(content).to match(/^idle_transaction_timeout = 0$/)
+        expect(content).to match(/^cancel_wait_timeout = 10$/)
         expect(content).to match(/^pkt_buf = 4096$/)
         expect(content).to match(/^listen_backlog = 128$/)
         expect(content).to match(/^sbuf_loopcnt = 5$/)
         expect(content).to match(/^max_packet_size = 2147483647$/)
+        expect(content).to match(/^so_reuseport = 0$/)
         expect(content).to match(/^tcp_defer_accept = 0$/)
         expect(content).to match(/^tcp_socket_buffer = 0$/)
         expect(content).to match(/^tcp_keepalive = 1$/)
@@ -141,6 +145,7 @@
         expect(content).not_to match(%r{^server_tls_cert_file =})
         expect(content).not_to match(%r{^max_db_connections =})
         expect(content).not_to match(%r{^max_user_connections =})
+        expect(content).not_to match(%r{^auth_dbname =})
       }
     end
 
@@ -222,6 +227,24 @@
           .with(user: 'fakeuser', group: 'gitlab-psql')
       end
     end
+
+    context 'peers' do
+      it 'configures the peers section' do
+        stub_gitlab_rb(
+          pgbouncer: {
+            enable: true,
+            peers: {
+              1 => { host: 'host1', port: '9001' },
+              2 => { host: 'host2', port: '9002' },
+            }
+          }
+        )
+        expect(chef_run).to render_file(pgbouncer_ini).with_content { |content|
+          expect(content).to match(%r{^1 = host=host1 port=9001$})
+          expect(content).to match(%r{^2 = host=host2 port=9002$})
+        }
+      end
+    end
   end
 
   context 'authentication' do
@@ -233,13 +256,15 @@
           pgbouncer: {
             enable: true,
             auth_hba_file: '/fake/hba_file',
-            auth_query: 'SELECT * FROM FAKETABLE'
+            auth_query: 'SELECT * FROM FAKETABLE',
+            auth_dbname: 'fakedb',
           }
         }
       )
       expect(chef_run).to render_file(pgbouncer_ini).with_content { |content|
         expect(content).to match(%r{^auth_hba_file = /fake/hba_file$})
         expect(content).to match(/^auth_query = SELECT \* FROM FAKETABLE$/)
+        expect(content).to match(/^auth_dbname = fakedb$/)
       }
     end