Module: DynamicMigrations::ActiveRecord::Migrators::Trigger

Included in:
DynamicMigrations::ActiveRecord::Migrators
Defined in:
lib/dynamic_migrations/active_record/migrators/trigger.rb

Defined Under Namespace

Classes: UnexpectedActionOrientationError, UnexpectedActionTimingError, UnexpectedConditionsError, UnexpectedEventManipulationError

Instance Method Summary collapse

Instance Method Details

#add_trigger(table_name, name:, action_timing:, event_manipulation:, action_orientation:, function_schema_name:, function_name:, parameters: [], action_condition: nil, action_reference_old_table: nil, action_reference_new_table: nil, comment: nil) ⇒ Object

create a postgres trigger



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# File 'lib/dynamic_migrations/active_record/migrators/trigger.rb', line 19

def add_trigger table_name, name:, action_timing:, event_manipulation:, action_orientation:, function_schema_name:, function_name:, parameters: [], action_condition: nil, action_reference_old_table: nil, action_reference_new_table: nil, comment: nil
  unless [:insert, :delete, :update].include? event_manipulation
    raise UnexpectedEventManipulationError, event_manipulation
  end

  unless action_condition.nil? || action_condition.is_a?(String)
    raise UnexpectedConditionsError, "expected String but got `#{action_condition}`"
  end

  unless [:row, :statement].include? action_orientation
    raise UnexpectedActionOrientationError, action_orientation
  end

  unless [:before, :after, :instead_of].include? action_timing
    raise UnexpectedActionTimingError, action_timing
  end

  # "INSTEAD OF/BEFORE/AFTER" "INSERT/UPDATE/DELETE"
  timing_sql = "#{action_timing.to_s.sub("_", " ")} #{event_manipulation}".upcase

  condition_sql = action_condition.nil? ? "" : "WHEN (#{action_condition})"

  temp_tables = []
  unless action_reference_old_table.nil?
    temp_tables << "OLD TABLE AS #{action_reference_old_table}"
  end
  unless action_reference_new_table.nil?
    temp_tables << "NEW TABLE AS #{action_reference_new_table}"
  end
  temp_tables_sql = temp_tables.any? ? "REFERENCING #{temp_tables.join(" ")}" : ""

  parameters_str = parameters.map { |p| quote(p) }.join(", ")

  # schema_name was not provided to this method, it comes from the migration class
  execute <<~SQL
    CREATE TRIGGER #{name}
      #{timing_sql} ON #{schema_name}.#{table_name} #{temp_tables_sql}
        FOR EACH #{action_orientation}
          #{condition_sql}
          EXECUTE FUNCTION #{function_schema_name}.#{function_name}(#{parameters_str});
  SQL

  if comment.is_a? String
    set_trigger_comment table_name, name, comment
  end
end

#after_delete(table_name, name:, function_schema_name:, function_name:, parameters: [], action_condition: nil, action_reference_old_table: nil, action_reference_new_table: nil, comment: nil) ⇒ Object 



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# File 'lib/dynamic_migrations/active_record/migrators/trigger.rb', line 87

def after_delete table_name, name:, function_schema_name:, function_name:, parameters: [], action_condition: nil, action_reference_old_table: nil, action_reference_new_table: nil, comment: nil
  add_trigger table_name, name: name, action_timing: :after, event_manipulation: :delete, action_orientation: :row, function_schema_name: function_schema_name, function_name: function_name, parameters: parameters, action_condition: action_condition, action_reference_old_table: action_reference_old_table, action_reference_new_table: action_reference_new_table, comment: comment
end

#after_insert(table_name, name:, function_schema_name:, function_name:, parameters: [], action_condition: nil, action_reference_old_table: nil, action_reference_new_table: nil, comment: nil) ⇒ Object 



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# File 'lib/dynamic_migrations/active_record/migrators/trigger.rb', line 79

def after_insert table_name, name:, function_schema_name:, function_name:, parameters: [], action_condition: nil, action_reference_old_table: nil, action_reference_new_table: nil, comment: nil
  add_trigger table_name, name: name, action_timing: :after, event_manipulation: :insert, action_orientation: :row, function_schema_name: function_schema_name, function_name: function_name, parameters: parameters, action_condition: action_condition, action_reference_old_table: action_reference_old_table, action_reference_new_table: action_reference_new_table, comment: comment
end

#after_update(table_name, name:, function_schema_name:, function_name:, parameters: [], action_condition: nil, action_reference_old_table: nil, action_reference_new_table: nil, comment: nil) ⇒ Object 



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# File 'lib/dynamic_migrations/active_record/migrators/trigger.rb', line 83

def after_update table_name, name:, function_schema_name:, function_name:, parameters: [], action_condition: nil, action_reference_old_table: nil, action_reference_new_table: nil, comment: nil
  add_trigger table_name, name: name, action_timing: :after, event_manipulation: :update, action_orientation: :row, function_schema_name: function_schema_name, function_name: function_name, parameters: parameters, action_condition: action_condition, action_reference_old_table: action_reference_old_table, action_reference_new_table: action_reference_new_table, comment: comment
end

#before_delete(table_name, name:, function_schema_name:, function_name:, parameters: [], action_condition: nil, action_reference_old_table: nil, action_reference_new_table: nil, comment: nil) ⇒ Object 



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# File 'lib/dynamic_migrations/active_record/migrators/trigger.rb', line 75

def before_delete table_name, name:, function_schema_name:, function_name:, parameters: [], action_condition: nil, action_reference_old_table: nil, action_reference_new_table: nil, comment: nil
  add_trigger table_name, name: name, action_timing: :before, event_manipulation: :delete, action_orientation: :row, function_schema_name: function_schema_name, function_name: function_name, parameters: parameters, action_condition: action_condition, action_reference_old_table: action_reference_old_table, action_reference_new_table: action_reference_new_table, comment: comment
end

#before_insert(table_name, name:, function_schema_name:, function_name:, parameters: [], action_condition: nil, action_reference_old_table: nil, action_reference_new_table: nil, comment: nil) ⇒ Object

wrappers for add_trigger which provide more friendly syntax



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# File 'lib/dynamic_migrations/active_record/migrators/trigger.rb', line 67

def before_insert table_name, name:, function_schema_name:, function_name:, parameters: [], action_condition: nil, action_reference_old_table: nil, action_reference_new_table: nil, comment: nil
  add_trigger table_name, name: name, action_timing: :before, event_manipulation: :insert, action_orientation: :row, function_schema_name: function_schema_name, function_name: function_name, parameters: parameters, action_condition: action_condition, action_reference_old_table: action_reference_old_table, action_reference_new_table: action_reference_new_table, comment: comment
end

#before_update(table_name, name:, function_schema_name:, function_name:, parameters: [], action_condition: nil, action_reference_old_table: nil, action_reference_new_table: nil, comment: nil) ⇒ Object 



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# File 'lib/dynamic_migrations/active_record/migrators/trigger.rb', line 71

def before_update table_name, name:, function_schema_name:, function_name:, parameters: [], action_condition: nil, action_reference_old_table: nil, action_reference_new_table: nil, comment: nil
  add_trigger table_name, name: name, action_timing: :before, event_manipulation: :update, action_orientation: :row, function_schema_name: function_schema_name, function_name: function_name, parameters: parameters, action_condition: action_condition, action_reference_old_table: action_reference_old_table, action_reference_new_table: action_reference_new_table, comment: comment
end

#remove_trigger(table_name, trigger_name) ⇒ Object 



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# File 'lib/dynamic_migrations/active_record/migrators/trigger.rb', line 91

def remove_trigger table_name, trigger_name
  execute <<~SQL
    DROP TRIGGER #{trigger_name} ON #{schema_name}.#{table_name};
  SQL
end

#remove_trigger_comment(table_name, trigger_name) ⇒ Object 



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# File 'lib/dynamic_migrations/active_record/migrators/trigger.rb', line 103

def remove_trigger_comment table_name, trigger_name
  execute <<~SQL
    COMMENT ON TRIGGER #{trigger_name} ON #{schema_name}.#{table_name} IS NULL;
  SQL
end

#set_trigger_comment(table_name, trigger_name, comment) ⇒ Object 



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# File 'lib/dynamic_migrations/active_record/migrators/trigger.rb', line 97

def set_trigger_comment table_name, trigger_name, comment
  execute <<~SQL
    COMMENT ON TRIGGER #{trigger_name} ON #{schema_name}.#{table_name} IS #{quote comment};
  SQL
end