Feature/dockerize backup directory

[shilongjaycui]

Eric here,

I've made a lot of changes toward what @shilongjaycui and @mathematicalmichael were going after here.

• Wrote a CLI bash script and dockerized it that does the same thing Jay's python script is supposed to do. It works for now. We can use the python version a bit later.
• Caused the docker image to be built in the awscdk-minecraft parent CDK app and pushed to an ECR repository. The "image URI" and ECR Repo ARN are then passed to the AWS batch job as environment variables. This way, the server-deployer CDK app has access to that reference. That app grants the EC2 instance pull access for the image.
• The docker-compose.yml on the EC2 instance successfully pulls the image and runs it (though there is an error right now when backups are attempted to be loaded into S3). I didn't experience this error locally, but I did on the EC2 instance.
• resolved a small bug in the frontend that prevented me from hitting the backend API to test this all
• Added an S3 bucket to the parent CDK app for the server backups. Passed the name of the bucket to the server-deployer app to grant the EC2 instance read/write access to the bucket.

The only issue at this point is that the backups don't seem to upload from the EC2 instance. Everything else seems to be working!

[phitoduck]

Here is an example user-data.sh script after it has been rendered. I got it by running cat /var/lib/cloud/instance/user-data.txt on the EC2 instance.

#!/bin/bash

# TODO: consider using try/catch expressions as shown in this SO answer: https://stackoverflow.com/questions/22009364/is-there-a-try-catch-command-in-bash
# to return a failure cfn-signal or success.

# This script is a templated string. All occurreces of "[dollar sign]<some var name>" will be substituted
# with other values by the CDK code.

# print the commands this script runs as they are executed
set -x

export WORKDIR=/minecraft
mkdir -p "$WORKDIR"
cd "$WORKDIR"

#########################################
# --- Install CLI tool dependencies --- #
#########################################

yum update -y
yum install -y docker

# install docker-compose and make the binary executable
curl -L https://github.com/docker/compose/releases/latest/download/docker-compose-$(uname -s)-$(uname -m) -o /usr/bin/docker-compose
chmod +x /usr/bin/docker-compose

# initialize docker and docker-swarm daemons
service docker start
docker swarm init

# install aws cli
yum install -y python3
pip3 install awscli --upgrade --user

# login to ECR and pull the minecraft server backup/restore image
aws ecr get-login-password --region us-west-2 | docker login --username AWS --password-stdin "630013828440.dkr.ecr.us-west-2.amazonaws.com"
docker pull "630013828440.dkr.ecr.us-west-2.amazonaws.com/awscdk-minecraft-mcdeployjobdefinitionminecraftserverbackupserviceimageminecraftbackupserviceecrrepo192beeb7-jwnlifcq2rzf"

# prepare a docker-compose.yml that runs the minecraft server and the backup service
cat << EOF > "$WORKDIR/docker-compose.yml"
version: '3.7'
services:
    minecraft:
        # image docs: https://github.com/itzg/docker-minecraft-server
        image: itzg/minecraft-server
        restart: always
        ports:
            - "25565:25565"
        environment:
            EULA: "TRUE"
            TYPE: "PAPER"
            VERSION: "1.19.3"
        volumes:
            - ./minecraft-data:/data
        networks:
        - minecraft-server
        deploy:
            replicas: 1

    # by default, this container will inherit the same IAM role as the EC2 host
    minecraft-backup:
        # aws s3 backup image with awscli and python3
        image: "630013828440.dkr.ecr.us-west-2.amazonaws.com/awscdk-minecraft-mcdeployjobdefinitionminecraftserverbackupserviceimageminecraftbackupserviceecrrepo192beeb7-jwnlifcq2rzf"
        volumes:
            - ./minecraft-data:/minecraft-data
        command: backup-on-interval
        environment:
            BACKUPS_BUCKET: "awscdk-minecraft-minecraftserverbackupsbucketce8b-18lbuip34jg7v"
            SERVER_DATA_DIR: /minecraft-data
            BACKUPS_S3_PREFIX: minecraft-server-backups
            BACKUP_INTERVAL_SECONDS: "600"
        deploy:
            replicas: 1

networks:
    minecraft-server:
        driver: overlay
        name: minecraft-server
EOF

# restore from backup if true is set to "true"
if [ "true" = "true" ]; then
    docker-compose run minecraft-backup restore || echo "Failed to restore from backup. Starting fresh..."
    docker network rm minecraft-server
fi

##########################################
# --- Start up the with docker swarm --- #
##########################################

# create a docker stack
# docker network create minecraft-server
docker stack deploy -c docker-compose.yml minecraft