# Applications

**Tips and Tricks** about some of my Docker Applications.

# Apache Guacamole

**Apache Guacamole** is a clientless remote desktop gateway. It supports standard protocols like VNC, RDP, and SSH.

# Docker Installation on ARM64

*Apache Guacamole is a powerful tool for managing remote connections, and installing it on a Raspberry Pi 4 with Docker allows for easy, remote access from almost anywhere*

---

## Prerequisites

1. Raspberry Pi 4
2. [Docker installed](https://wiki.boreux.work/books/set-up/page/docker-installation-on-raspberry-pi-4-raspberrypi-os)


## Docker Compose Setup

For this installation, we will use a `compose.yaml` file with Docker Compose to manage the Guacamole installation.

<div class="callout info">I’m using the <a href="https://hub.docker.com/r/flcontainers/guacamole">flcontainers/guacamole</a> Docker image, which is compatible with the ARM64 architecture, unlike the official image.</div>

Here’s what the `compose.yaml` file should look like:

```yaml
services:
    guacamole_app:
        container_name: guacamole_app
        image: flcontainers/guacamole:latest
        restart: unless-stopped
        ports:
            - 8094:8080
        volumes:
            - guacamole_app-config:/config
            - /etc/localtime:/etc/localtime:ro
        environment:
            TZ: 'Europe/Brussels'
        healthcheck:
            test: curl -f -k http://127.0.0.1:8080/ || exit 1
            interval: 15s
            timeout: 10s
            retries: 5

volumes:
    guacamole_app-config:
        name: guacamole_app-config
```


## Installation

Once you’ve created the `compose.yaml` file, navigate to the directory where it’s stored and run the following command:

```bash
docker compose up -d
```

This command will pull the Guacamole image and install it on your Raspberry Pi.


## Using Apache Guacamole

After the installation, you can access the Guacamole web interface by visiting http://<YOUR_RPI_IP>:8094

<div class="callout info">
<b>Username:</b> guacadmin<br>
<b>Password:</b> guacadmin
</div>

---

With this setup, you now have Apache Guacamole running on your Raspberry Pi 4, allowing easy remote desktop access and management.

Happy me! 🌱

# Bookstack

**BookStack** is a simple, open-source, self-hosted, easy-to-use platform for organising and storing information.

# Changing the Base URL

*Sometimes, you need to change the base URL of Bookstack, for example, when you switch from the localhost address to the internet exposed address.*

---

## Docker Compose

In your `compose.yaml`, modify the following environment variable:

```
APP_URL=<new_url>
```

## Bookstack Container

Open a terminal and type:

```
docker exec -it <bookstack_container> php /app/www/artisan bookstack:update-url <old_url> <new_url>
```

## Clear Cache

Open a terminal and type:

```
docker exec -it <bookstack_container>  php /app/www/artisan cache:clear
```

# Paperless-ngx

**Paperless-ngx** is a document management system that transforms your physical documents into a searchable online archive.

# Backup & Restore

*Here is the procedure to backup and restore the Paperless-NGX application and all of its data.*

---

## Backup

On a terminal, enter the following command:

```bash
docker compose exec -T <paperless_webserver> document_exporter -z ../export
```

Where:

- `-T` is used to suppress "The input device is not a TTY" error ;
- `-z` is used to zip the export ;
- `../export` is used because this path inside the container is automatically mounted on your host on the folder export.

## Restore

**You'll need to unzip the previous export!**

On a terminal, enter the following command:

```bash
docker compose exec -T <paperless_webserver> document_importer ../export/<unzipped_directory>/
```

Where:

- `-T` is used to suppres "The device is not a TTY" error ;
- `../export/<unzipped_directory>/` is the path to your previous backup unzipped.

# Consumption fails with "Ghostscript PDF/A rendering failed"

When updating Paperless-NGX, you may get the following error:

<p class="callout danger">Consumption fails with "Ghostscript PDF/A rendering failed"
Newer versions of OCRmyPDF will fail if it encounters errors during processing. This is intentional as the output archive file may differ in unexpected or undesired ways from the original. As the logs indicate, if you encounter this error you can set PAPERLESS_OCR_USER_ARGS: '{"continue_on_soft_render_error": true}' to try to 'force' processing documents with this issue.</p>

To fix this, you can:

1. Go to your paperless web interface
2. Go to **Configuration** menu
3. Go to **OCR Settings** tab
4. In the **OCR Arguments** tile, enter `{"continue_on_soft_render_error": true}`
5. Save

And, the error is fixed!

# Creating a Super User

If you don't have a super user with your Paperless-NGX installation, you can create one with a command.

```bash
docker compose exec -it <PAPERLESS CONTAINER> createsuperuser

> Username (leave blank to use 'paperless'): 
> Email address: 
> Password: 
> Password (again):
> Superuser created successfully.
```

# ntfy

**ntfy** lets you send push notifications to your phone or desktop via scripts from any computer, using simple HTTP PUT or POST requests.

# 🔔 Low Space

## Script

```bash
#!/bin/bash

mingigs=20
avail=$(df | awk '$6 == "/" && $4 < '$mingigs' * 1024*1024 { print $4/1024/1024 }')

if [ -n "$avail" ]; then
  curl \
      -H "Title: Low Disk Space" \
      -H "Priority: urgent" \
      -H "Tags: warning,cd" \
      -d "Hello TTBB! Only $avail GB available on the root disk. Better clean that up." \
      https://notify.boreux.work/raspberrypi?auth=<TOKEN>
fi
```

## Cron

```bash
0  *    * * *   root    /bin/bash /root/ntfy/low-disk-space.sh
```

# ⛔️ SSH Access

## Script

```bash
#!/bin/bash
if [ "${PAM_TYPE}" = "open_session" ]; then
  curl \
      -H "Title: SSH Login" \
      -H "Priority: urgent" \
      -H "Tags: warning,door" \
      -d "Hello TTBB! There was an SSH login with user ${PAM_USER} from ${PAM_RHOST} host" \
      https://notify.boreux.work/pihole?auth=<TOKEN>
fi
```

## `/etc/pam.d/sshd`

At the end of the file, add the following line:

```bash
session optional pam_exec.so /root/ntfy/ssh-login.sh
```

# 🐚 Useful Commands

## Creating an Administrator

```bash
docker exec -it <NTFY_CONTAINER_NAME> ntfy user add --role=admin <USERNAME>
```

# Vikunja

The to-do app to organize your life

# Quick Add Magic

# Quick Add Magix Syntax Cheatsheet

## Labels - `*`

```
*"Label with spaces"
```

## Project - `+`

```
+"Project with spaces"
```

## Due Date and Time

<p class="callout danger">The date format is: MM/DD/YYYY</p>

```
02/17/2021 at 17:00
```

## Assignee

```
@ttbb
```

## Examples

- `dishwasher +HOUSE *kitchen 04/05/2025 at 09:00 @ttbb`
- `washing machine +HOUSE *bathroom  04/05/2025 at 09:00 @ttbb`
- `clean surfaces +HOUSE *kitchen  04/05/2025 at 09:30 @ttbb`
- `trash +HOUSE *kitchen  04/05/2025 at 09:45 @ttbb`
- `clean surfaces +HOUSE *living  04/05/2025 at 10:00 @ttbb`
- `clean toilet +HOUSE *toilets  04/05/2025 at 10:30 @ttbb`
- `clean surfaces +HOUSE *bathroom  04/05/2025 at 11:00 @ttbb`
- `vacuum +HOUSE *house 04/05/2025 at 11:30 @ttbb`
- `wash the floors +HOUSE *house 04/05/2025 at 12:00 @ttbb`
- `clean shower +HOUSE *bathroom  04/05/2025 at 12:30 @ttbb`