introduce max_lock_timeout

Author: MouadHilali

lib/safe-pg-migrations/configuration.rb

@@ -12,10 +12,11 @@ class Configuration
                     backfill_pause
                     retry_delay
                     max_tries
+                    max_lock_timeout
                     sensitive_logger
                     lock_timeout
-                    safe_timeout
                   ])
+    attr_reader :safe_timeout
 
     def initialize
       self.default_value_backfill_threshold = nil
@@ -27,6 +28,7 @@ def initialize
       self.backfill_pause = 0.5.second
       self.retry_delay = 1.minute
       self.max_tries = 5
+      self.max_lock_timeout = 1.second
       self.sensitive_logger = nil
     end
 
@@ -43,7 +45,7 @@ def lock_timeout=(value)
     def safe_timeout=(value)
       raise 'Setting safe timeout to 0 disables the safe timeout and is dangerous' unless value
 
-      unless lock_timeout.nil? || value > lock_timeout
+      unless lock_timeout.nil? || value > lock_timeout || value > max_lock_timeout
         raise ArgumentError, "Safe timeout (#{value}) cannot be less than lock timeout (#{lock_timeout})"
       end
 

lib/safe-pg-migrations/plugins/statement_retrier.rb

@@ -13,21 +13,18 @@ module StatementRetrier
     private
 
     def retry_if_lock_timeout
-      remaining_tries = SafePgMigrations.config.max_tries
+      number_of_retries = 0
       begin
-        remaining_tries -= 1
+        number_of_retries += 1
         yield
       rescue ActiveRecord::LockWaitTimeout
         raise if transaction_open? # Retrying is useless if we're inside a transaction.
-        raise unless remaining_tries > 0
+        raise if number_of_retries >= SafePgMigrations.config.max_tries
 
-        number_of_retries = SafePgMigrations.config.max_tries - remaining_tries
-        if SafePgMigrations.config.max_tries - remaining_tries <= 20
+        if SafePgMigrations.config.lock_timeout < SafePgMigrations.config.max_lock_timeout
           SafePgMigrations.config.lock_timeout = SafePgMigrations.config.lock_timeout * number_of_retries
-          SafePgMigrations.config.safe_timeout = SafePgMigrations.config.safe_timeout * number_of_retries
         else
-          SafePgMigrations.config.lock_timeout = SafePgMigrations.config.lock_timeout * 20
-          SafePgMigrations.config.safe_timeout = SafePgMigrations.config.safe_timeout * 20
+          SafePgMigrations.config.lock_timeout = SafePgMigrations.config.max_lock_timeout
         end
 
         retry_delay = SafePgMigrations.config.retry_delay