Automation – How to Put a Trigger on a Directory

automation

I have a script that scans a directory and does some maintenance on the files in it. Another process creates the files in the directory (10 – 30 files per day).

The script is called via a daily cron job . What I need is to trigger the script on an event (each time a new file is created in the directory). I prefer this rather than increasing the frequency of the cron job.

How can I do that? is there a command or a program to install?

Thanks in advance for any help.

Best Answer

inoticoming

inoticoming is a daemon to watch a directory with Linux's inotify framework and trigger actions once files with specific names are placed in there.

For example it can be used to wait for .changes files uploaded into a directory and call reprepro to put them into your repository.

Manual page of inoticoming

incron

incron is an "inotify cron" system. It works like the regular cron but is driven by filesystem events instead of time events. This package provides two programs, a daemon called "incrond" (analogous to crond) and a table manipulator "incrontab" (like "crontab").

incron uses the Linux Kernel inotify syscalls.

like cron, each user can edit its own incron tables.

AzuraCast: A Self-Hosted Web Radio Manager

Source: https://github.com/AzuraCast/AzuraCast

Azuracast is a self-hosted web radio management suite, including turnkey installer tools and an easy-to-use web app to manage your stations. http://azuracast.com/

Features

With AzuraCast, you can:

Manage your Media: Upload songs from the web, organize music into folders, and preview songs in your browser.
Create Playlists: Set up standard playlists that play all the time, scheduled playlists for time periods, or special playlists that play once per x songs, or once per x minutes.
Set Up Live DJs: Enable or disable live broadcasting from streamers/DJs, and create individual accounts for each streamer to use.
Take Listener Requests: Let your listeners request specific songs from your playlists, both via an API and a simple public-facing listener page.
Analytics and Reports: Keep track of every aspect of your station's listeners over time. View reports of each song's performance.
Station Autopilot: AzuraCast can automatically assign songs to a playlist based on the song's impact on listener numbers.
Delegate Management: Create and remove separate administrator accounts for each station manager.
...and more.

Supported Web Radio Software

AzuraCast uses LiquidSoap as an "AutoDJ" to shuffle songs and playlists and provide an always-online radio stream. You can connect to LiquidSoap and broadcast your own live events as a DJ as well.
To broadcast your radio station to the public, AzuraCast supports both of the gold standards in web radio, IceCast (v2.4) and ShoutCast (v2). You can switch which of these your station uses anytime you want.

You can also use AzuraCast as a tool for relaying or collecting listener statistics and other data about stations that AzuraCast doesn't manage.

Supported Operating Systems

There are two ways to install AzuraCast:

Using Docker and Docker Compose (Recommended): This method contains all of the AzuraCast dependencies in prebuilt container images. Updating and installing is faster, and there are far fewer issues with software compatibility. This method works on any computer that supports the latest version of the Docker Engine and Docker Compose; both can be installed as part of the AzuraCast installer script.
Traditional Installation (Ubuntu 16.04 only): From a clean image of Ubuntu, you can install AzuraCast directly onto your server using the included installer scripts, which use Ansible to manage dependencies. Installation and updating are slower using this method, but you have more control over the software once installed. If you have other software installed on your server, it may conflict with AzuraCast, so always start from a clean installation using this method.

We are always looking to expand our compatibility with host operating systems, and we welcome any assistance in building new deployment scripts for other environments.

What's Included with AzuraCast

Whether you're using the traditional installer or Docker containers, AzuraCast depends on the same stack of software to operate:

NGINX for serving web pages and the radio proxy
MariaDB as the primary database
PHP 7.2 powering the web application
InfluxDB for time-series based statistics
Redis for sessions, database and general caching
LiquidSoap as the always-playing "AutoDJ"
IceCast 2 as a radio broadcasting frontend (Icecast-KH installed on supported platforms)
ShoutCast 2 DNAS as an alternative radio frontend (x86/x64 only) Installing AzuraCast

Installing AzuraCast

Docker Installation (Recommended)

We strongly recommend installing and using AzuraCast via Docker. All of the necessary software packages are built by our automated tools, so installation is as easy as just pulling down the pre-compiled images. There's no need to worry about compatibility with your host operating system, so any host (including Windows and MacOS) will work great out of the box.

Install Docker and Docker Compose Your computer or server should be running the newest version of Docker and Docker Compose. You can use the easy scripts below to install both if you're starting from scratch:

wget -qO- https://get.docker.com/ | sh
COMPOSE_VERSION=`git ls-remote https://github.com/docker/compose | grep refs/tags | grep -oP "[0-9]+\.[0-9][0-9]+\.[0-9]+$" | tail -n 1`
sudo sh -c "curl -L https://github.com/docker/compose/releases/download/${COMPOSE_VERSION}/docker-compose-`uname -s`-`uname -m` > /usr/local/bin/docker-compose"
sudo chmod +x /usr/local/bin/docker-compose
sudo sh -c "curl -L https://raw.githubusercontent.com/docker/compose/${COMPOSE_VERSION}/contrib/completion/bash/docker-compose > /etc/bash_completion.d/docker-compose"

If you're not installing as root, you may be given instructions to add your current user to the Docker group (i.e. usermod -aG docker $user). You should log out or reboot after doing this before continuing below.

Pull the AzuraCast Docker Compose File

Choose where on the host computer you would like AzuraCast's configuration file to exist on your server.

Inside that directory, run this command to pull the Docker Compose configuration file.
```
curl -L https://raw.githubusercontent.com/AzuraCast/AzuraCast/master/docker-compose.yml > docker-compose.yml
```
Run the AzuraCast Docker Installer

From the directory that contains your YML configuration file, run these commands:
```
docker-compose pull  
docker-compose run --rm cli azuracast_install
docker-compose up -d
```

Setting up HTTPS with LetsEncrypt

AzuraCast now supports full encryption with LetsEncrypt. LetsEncrypt offers free SSL certificates with easy validation and renewal.

First, make sure your AzuraCast instance is set up and serving from the domain you want to use. Then, run the following command to generate a new LetsEncrypt certificate:

docker-compose run --rm letsencrypt certonly --webroot -w /var/www/letsencrypt

You will be prompted to specify your e-mail address and domain name. Validation will happen automatically. Once complete, run this command to tell nginx to use your new LetsEncrypt certificate:

docker-compose run --rm nginx letsencrypt_connect YOURDOMAIN.example.com

Reload nginx using the command below:

docker-compose kill -s SIGHUP nginx

Your LetsEncrypt certificate is valid for 3 months. To renew the certificates, run this command:

docker-compose run --rm letsencrypt renew --webroot -w /var/www/letsencrypt

Updating with Docker

From inside the base directory where AzuraCast is copied, run the following commands:

docker-compose down
docker-compose pull
docker-compose run --rm cli azuracast_update  
docker-compose up -d

Docker Volume Backup and Restore

AzuraCast has utility scripts to allow for easy backup and restoration of Docker volumes.

You can use docker-backup.sh to back up existing volumes. You can specify a custom path as the script's argument. By default, the script will create a file, backup.tar.gz in the app root.

To restore the application's state from this compressed file use docker-restore.sh and provide it with the path of the existing backup file.

Note that the restoration process will replace any existing AzuraCast database or media that exists inside the Docker volumes.

Traditional Installation (Ubuntu 16.04 only)

Note: Some web hosts offer custom versions of Ubuntu that include different software repositories. These may cause compatibility issues with AzuraCast. Many VPS providers are known to work out of the box with AzuraCast (OVH, DigitalOcean, Vultr, etc), and are thus highly recommended if you plan to use the traditional installer.

AzuraCast is optimized for speed and performance, and can run on very inexpensive hardware, from the Raspberry Pi 3 to the lowest-level VPSes offered by most providers.

Since AzuraCast installs its own radio tools, databases and web servers, you should always install AzuraCast on a "clean" server instance with no other web or radio software installed previously.

Execute these commands as the root user to set up your AzuraCast server:

apt-get update
apt-get install -q -y git
mkdir -p /var/azuracast/www
cd /var/azuracast/www
git clone https://github.com/AzuraCast/AzuraCast.git .
chmod a+x install.sh
./install.sh

If you cannot directly log in as the root account on your server, try running sudo su before running the commands above.

The installation process will take between 5 and 15 minutes, depending on your internet connection.

Once the terminal-based installation is complete, you can visit your server's public IP address (http://ip.of.your.server/) to finish the web-based setup.

Updating

AzuraCast also includes a handy updater script that pulls down the latest copy of the codebase from Git, flushes the site caches and makes any necessary database updates. Run these commands as any user with sudo permissions:

cd /var/azuracast/www
sudo chmod a+x update.sh
sudo ./update.sh