paper_trail

# PaperTrail

[![Build Status][4]][5]
[![Gem Version][53]][54]
[![SemVer][55]][56]

Track changes to your models, for auditing or versioning. See how a model looked
at any stage in its lifecycle, revert it to any version, or restore it after it
has been destroyed.

## Documentation

This is the _user guide_. See also, the
[API reference](https://www.rubydoc.info/gems/paper_trail).

Choose version:
[Unreleased](https://github.com/paper-trail-gem/paper_trail/blob/master/README.md),
[17.0](https://github.com/paper-trail-gem/paper_trail/blob/v17.0.0/README.md),
[16.0](https://github.com/paper-trail-gem/paper_trail/blob/v16.0.0/README.md),
[15.2](https://github.com/paper-trail-gem/paper_trail/blob/v15.2.0/README.md),
[14.0](https://github.com/paper-trail-gem/paper_trail/blob/v14.0.0/README.md),
[13.0](https://github.com/paper-trail-gem/paper_trail/blob/v13.0.0/README.md),
[12.3](https://github.com/paper-trail-gem/paper_trail/blob/v12.3.0/README.md),
[11.1](https://github.com/paper-trail-gem/paper_trail/blob/v11.1.0/README.md),
[10.3](https://github.com/paper-trail-gem/paper_trail/blob/v10.3.1/README.md),
[9.2](https://github.com/paper-trail-gem/paper_trail/blob/v9.2.0/README.md),
[8.1](https://github.com/paper-trail-gem/paper_trail/blob/v8.1.2/README.md),
[7.1](https://github.com/paper-trail-gem/paper_trail/blob/v7.1.3/README.md),
[6.0](https://github.com/paper-trail-gem/paper_trail/blob/v6.0.2/README.md),
[5.2](https://github.com/paper-trail-gem/paper_trail/blob/v5.2.3/README.md),
[4.2](https://github.com/paper-trail-gem/paper_trail/blob/v4.2.0/README.md),
[3.0](https://github.com/paper-trail-gem/paper_trail/blob/v3.0.9/README.md),
[2.7](https://github.com/paper-trail-gem/paper_trail/blob/v2.7.2/README.md),
[1.6](https://github.com/paper-trail-gem/paper_trail/blob/v1.6.5/README.md)

## Table of Contents

<!-- toc -->

- [1. Introduction](#1-introduction)
  - [1.a. Compatibility](#1a-compatibility)
  - [1.b. Installation](#1b-installation)
  - [1.c. Basic Usage](#1c-basic-usage)
  - [1.d. API Summary](#1d-api-summary)
  - [1.e. Configuration](#1e-configuration)
- [2. Limiting What is Versioned, and When](#2-limiting-what-is-versioned-and-when)
  - [2.a. Choosing Lifecycle Events To Monitor](#2a-choosing-lifecycle-events-to-monitor)
  - [2.b. Choosing When To Save New Versions](#2b-choosing-when-to-save-new-versions)
  - [2.c. Choosing Attributes To Monitor](#2c-choosing-attributes-to-monitor)
  - [2.d. Turning PaperTrail Off](#2d-turning-papertrail-off)
  - [2.e. Limiting the Number of Versions Created](#2e-limiting-the-number-of-versions-created)
- [3. Working With Versions](#3-working-with-versions)
  - [3.a. Reverting And Undeleting A Model](#3a-reverting-and-undeleting-a-model)
  - [3.b. Navigating Versions](#3b-navigating-versions)
  - [3.c. Diffing Versions](#3c-diffing-versions)
  - [3.d. Deleting Old Versions](#3d-deleting-old-versions)
  - [3.e. Queries](#3e-queries)
  - [3.f. Defunct `item_id`s](#3f-defunct-item_ids)
- [4. Saving More Inform