Basic Docker support (#141)

* Create Dockerfile

Creating a basic Dockerfile so spotify_dl can be shipped as an image

* Create bulk downloading script for Docker

Creating a bash script for parallel bulk downloading of Spotify playlists.

* Update GETTING_STARTED to include Docker instructions

Dockerfile

@@ -0,0 +1,11 @@
+# Use an official Python runtime as a base image
+FROM python:3.8-slim
+
+# Install any needed packages specified in requirements.txt
+RUN apt-get update
+RUN apt-get install -y ffmpeg
+RUN pip3 install spotify_dl --upgrade
+
+# Define environment variable
+ENV SPOTIPY_CLIENT_ID=
+ENV SPOTIPY_CLIENT_SECRET=

GETTING_STARTED.md

@@ -37,6 +37,22 @@ Pre-requisite: You need Python 3.6+
   - Linux users can get them by installing libav-tools by using apt-get (`sudo apt-get install -y libav-tools`) or a package manager which comes with your distro
   - Windows users can download FFMPEG pre-built binaries from [here](http://ffmpeg.zeranoe.com/builds/). Extract the file using [7-zip](http://7-zip.org/) to a foldrer and [add the folder to your PATH environment variable](http://www.wikihow.com/Install-FFmpeg-on-Windows) 
 
+### Use Docker
+
+Build the Docker image from the Dockerfile, run the following command in the spotify_dl root directory: `docker build -t spotify_dl .`
+
+Run the Docker image with your client ID and secret:
+``` bash
+docker run -d --rm \
+		   -e SPOTIPY_CLIENT_ID=client_id \
+		   -e SPOTIPY_CLIENT_SECRET=client_secret \
+		   -v "`pwd`":/download \
+		   spotify_dl \
+		   spotify_dl -l "spotify_playlist_link" -o download_directory
+```
+
+You can also run the bulk downloading script, make sure to configure it first: `bash bulk_docker_download.sh`
+
 ### How do I set defaults?
 
 You can set defaults per user by creating a file at `~/.spotify_dl_settings`. Create a key with value for every argument you want a default for. Example:

bulk_docker_download.sh

@@ -0,0 +1,34 @@
+#!/bin/sh
+
+# Information: The docker image has to be previously built and tagged with spotify_dl[:latest]
+# Use 'docker build -t spotify_dl .' inside the project directory to build the Docker container
+
+# Specify download location, use pwd for current directory
+location="`pwd`"
+
+# Declare list with playlists to download
+declare -a playlists=( \
+	"https://open.spotify.com/PLAYLIST_LINK" "Playlist Name" \
+	"https://open.spotify.com/PLAYLIST_LINK" "Playlist Name" \
+)
+
+# Set client ID and secret
+client_id=sampleid123
+client_secret=samplesecret123
+
+arraylength=${#playlists[@]}
+
+for (( i=1; i<${arraylength}+1; i=i+2 ));
+do
+	echo "Downloading playlist: ${playlists[$i-1]}"
+	path="$location/${playlists[$i]}"
+	echo "Creating dir: $path"
+	mkdir -p "$path"
+	echo "Starting container: " $(echo "spotify_dl-${playlists[$i]//[^[:alnum:]]/}" | sed 's/ä/ae/;s/ö/oe/;s/ü/ue/;s/ß/ss/g')
+	docker run -d --rm --name $(echo "spotify_dl-${playlists[$i]//[^[:alnum:]]/}" | sed 's/ä/ae/;s/ö/oe/;s/ü/ue/;s/ß/ss/g') \
+		   -e SPOTIPY_CLIENT_ID=$client_id \
+		   -e SPOTIPY_CLIENT_SECRET=$client_secret \
+		   -v "$location":/download \
+		   spotify_dl \
+		   spotify_dl -l "${playlists[$i-1]}" -o /download &
+done