Module: FastDestroyAll

Extended by:
ActiveSupport::Concern
Included in:
Ci::BuildTraceChunk, Deployment
Defined in:
app/models/concerns/fast_destroy_all.rb

Overview

This module is for replacing ‘dependent: :destroy` and before_destroy hooks.

In general, destroy_all is inefficient because it calls each callback with DELETE queries i.e. O(n), whereas, delete_all is efficient as it deletes all rows with a single DELETE query.

It’s better to use delete_all as our best practice, however, if external data (e.g. ObjectStorage, FileStorage or Redis) are associated with database records, it is difficult to accomplish it.

This module defines a format to use delete_all and delete associated external data. Here is an example

Situation

  • Project has many Ci::BuildTraceChunk through Ci::Build

  • Ci::BuildTraceChunk stores associated data in Redis,

    so it relies on `dependent: :destroy` and `before_destroy` for the deletion

How to use

  • Define ‘use_fast_destroy :build_trace_chunks` in Project model.

  • Define begin_fast_destroy and ‘finalize_fast_destroy(params)` in Ci::BuildTraceChunk model.

  • Use fast_destroy_all instead of destroy and destroy_all

  • Remove ‘dependent: :destroy` and before_destroy as it’s no longer need

Expectation

  • When a project is ‘destroy`ed, the associated trace_chunks will be deleted by delete_all, and the associated data will be removed, too.

  • When fast_destroy_all is called, it also performns as same.

Defined Under Namespace

Modules: Helpers

Constant Summary collapse

ForbiddenActionError = 
Class.new(StandardError)