recovering-deleted-wagtail-pages/slides.md

---
title: Recovering deleted Wagtail pages and Django models
class: text-center
highlighter: shiki
transition: slide-left
mdc: true
themeConfig:
  primary: '#fd5765'
---

# Recovering [deleted]{style="color: #fd5765"} Wagtail pages and/or Django models

### Jake Howard{style="color: #e85537;" .mt-10 }

<ul class="list-none! text-sm [&>li]:m-0! mt-1 uppercase">
  <li>Senior Systems Engineer @ Torchbox</li>
  <li>Core Team, Security Team & Performance Working Group @ Wagtail</li>
</ul>

<ul class="list-none! text-sm [&>li]:m-0! mt-3">
  <li><mdi-earth /> theorangeone.net</li>
  <li><mdi-twitter /> @RealOrangeOne</li>
  <li><mdi-github /> @RealOrangeOne</li>
  <li><mdi-mastodon /> @jake@theorangeone.net</li>
</ul>

---
layout: cover
background: /intranet.png
---

# Setting the scene

---
layout: cover
background: /site-history.png
---

# Site history report

---
layout: image
image: /chat.png
backgroundSize: contain
---

---
layout: section
---

# Restoring from backups

---
layout: section
---

# _Partially_ restoring from backups

---
layout: section
---

## 1.
# Spin up a database backup

---
layout: section
---

## 2.
# Locate the page models

<div class="pt-5">

```python
from wagtail.models import Page

sysadmin_page = Page.objects.get(id=91)

child_pages = sysadmin_page.get_descendants()
```

</div>

<style>
  pre.shiki {
    font-size: 1.4rem !important;
    text-align: left;
  }
</style>

---
layout: section
---

## 3.
# Locate what was deleted

<div class="pt-5">

```python
from django.contrib.admin.utils import NestedObjects

collector = NestedObjects()
collector.collect(list(child_pages) + [sysadmin_page])
```

</div>

<style>
  pre.shiki {
    font-size: 1.4rem !important;
    text-align: left;
  }
</style>


---
layout: section
---

# 4. Serialize

<div class="pt-5">

```python {all|3-5|all}
from django.core import serializers

class NoM2MSerializer(Serializer):
    def handle_m2m_field(self, obj, field):
        pass

def get_model_instances():
    for qs in collector.data.values():
        yield from qs

with open("deleted-models.json", "w") as f:
    NoM2MSerializer().serialize(
        get_model_instances(),
        stream=f
    )
```

</div>

<style>
  pre.shiki {
    font-size: 1rem !important;
    text-align: left;
  }
</style>


---
layout: section
---

## 4a.
# [De]{.italic}serialize

### `manage.py loaddata`

---
layout: center
---

# `restore-deleted-pages.py`

```python {all}{lines:true}
from django.contrib.admin.utils import NestedObjects
from django.core import serializers

from wagtail.models import Page

class NoM2MSerializer(Serializer):
    def handle_m2m_field(self, obj, field):
        pass

sysadmin_page = Page.objects.get(id=91)

child_pages = sysadmin_page.get_descendants()

collector = NestedObjects()
collector.collect(list(child_pages) + [sysadmin_page])

def get_model_instances():
    for qs in collector.data.values():
        yield from qs

with open("deleted-models.json", "w") as f:
    NoM2MSerializer().serialize(
        get_model_instances(),
        stream=f
    )
```

---
layout: fact
---

### 5.
# **Test!**

---
layout: image-right
image: /red-button.png
class: flex justify-center flex-col items-center
---

### 6.
# Showtime!

---
layout: image-right
image: https://images.unsplash.com/photo-1622021134395-d26aab83c221?q=80&w=1470&auto=format&fit=crop&ixlib=rb-4.0.3&ixid=M3wxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHx8fA%3D%3D
class: flex justify-center flex-col text-xl
---

1. Backup!
2. Transfer `deleted-models.json` to server
3. `loaddata`
4. `checktree`
5. `update_index`
6. `rebuild_reference_index`

---
layout: cover
background: /sysadmin.png
---

# Conclusion

---
layout: end
---

END