Miniswarm - Local docker swarm in one command

What is Miniswarm?

Miniswarm is a tool that intends to make creating a Docker swarm cluster locally as easy as possible. Miniswarm was inspired by Minikube which does a similar thing for kubernetes clusters.

Prerequisites

• Docker >= 1.12
• docker-machine >= 0.7.0
• Virtualbox

Miniswarm and docker swarm healthchecks tutorial

I like to learn by doing, hopefully you do too. Lets install miniswarm, deploy our swarm cluster and some apps.

install

curl -sL https://raw.githubusercontent.com/aelsabbahy/miniswarm/master/miniswarm -o /usr/local/bin/miniswarm
chmod +rx /usr/local/bin/miniswarm

start a cluster - Pick your desired size

# 1 manger 2 workers
miniswarm start 3

# 1 manager cluster - if you want a smaller cluster
miniswarm start

# 2 mangers 3 workers - nice laptop or desktop :)
miniswarm start 2 3

A couple of minutes later, you should get this message

INFO: Stack starup complete. To connect to your stack, run the following command:
INFO: eval $(docker-machine env ms-manager0)

visualize your cluster

This will open a browser with a nice visualization of your docker swarm using docker-swarm-visualizer

miniswarm vis

Deploy our first service

This service will be unhealthy due to failing Goss healthchecks and missing dependencies. See next few steps for how we can debug and remedy this.

# Connect to our swarm
eval $(docker-machine env ms-manager0)

# Create a network for our service
docker network create healthyvote_net -d overlay

# Ensure network is set to driver=overlay, scope=swarm
docker network ls

# Create our first service
docker service create -p 8080:80 --replicas 2 --network healthyvote_net --name vote aelsabbahy/healthyvote

Inspect the service health

# This should show the service not running
docker service ls
docker service ps vote

# Lets look at the healthchecks using miniswarm
# -a shows all containers, including exited/failed containers
miniswarm health vote -a

We should see something like this:

[ms-worker0 vote.2.630mookf9pnc8dip5hl7yng3q] ======
[ms-worker0 vote.2.630mookf9pnc8dip5hl7yng3q] Start: 2016-08-07 22:39:03.748704565 +0000 UTC
[ms-worker0 vote.2.630mookf9pnc8dip5hl7yng3q] ======
[ms-worker0 vote.2.630mookf9pnc8dip5hl7yng3q] .F
[ms-worker0 vote.2.630mookf9pnc8dip5hl7yng3q]
[ms-worker0 vote.2.630mookf9pnc8dip5hl7yng3q] Failures/Skipped:
[ms-worker0 vote.2.630mookf9pnc8dip5hl7yng3q]
[ms-worker0 vote.2.630mookf9pnc8dip5hl7yng3q] Title: Redis backend is reachable
[ms-worker0 vote.2.630mookf9pnc8dip5hl7yng3q] Meta:
[ms-worker0 vote.2.630mookf9pnc8dip5hl7yng3q]     remedy.1: Deploy redis service if you haven't already
[ms-worker0 vote.2.630mookf9pnc8dip5hl7yng3q]     remedy.2: ctrl-alt-delete
[ms-worker0 vote.2.630mookf9pnc8dip5hl7yng3q]     remedy.3: take a nap aka human ctrl-alt-delete
[ms-worker0 vote.2.630mookf9pnc8dip5hl7yng3q] Addr: tcp://redis:6379: reachable:
[ms-worker0 vote.2.630mookf9pnc8dip5hl7yng3q] Expected
[ms-worker0 vote.2.630mookf9pnc8dip5hl7yng3q]     <bool>: false
[ms-worker0 vote.2.630mookf9pnc8dip5hl7yng3q] to equal
[ms-worker0 vote.2.630mookf9pnc8dip5hl7yng3q]     <bool>: true
[ms-worker0 vote.2.630mookf9pnc8dip5hl7yng3q]
[ms-worker0 vote.2.630mookf9pnc8dip5hl7yng3q] Total Duration: 0.500s
[ms-worker0 vote.2.630mookf9pnc8dip5hl7yng3q] Count: 2, Failed: 1, Skipped: 0

Deploy missing dependencies

Lets remedy the healthcheck issue

docker service create --replicas 1 --network healthyvote_net --name redis redis

# Wait for it to show up in `miniswarm vis` or by using CLI
docker service ls

# Now that redis is deployed, lets if our vote service is running
docker service ls

# And the health..
miniswarm health vote

Open service in browser

# Open app in browser
miniswarm service vote

# print url, but don't open
miniswarm service vote --url

View the logs

miniswarm logs vote

# Tail the log file (-f has to be at the end for now)
miniswarm logs redis -f

Delete our swarm cluster

miniswarm delete

FAQ

Why the #$@^%$ is this written in Bash?

Two reasons:

1. I though it was going to be ~100 lines of bash, I was wrong.. very wrong :(.
2. I want users to be able to look at this script and see all the commands needed to set up a swarm cluster.

• Go would be great for this tool, especially by leveraging the docker packages directly, but then the tool will be more of a blackbox to new users

Why did you use Goss for healthchecks?

Mostly shameless self-promotion, and while we're on the topic, check out:

• Goss - Project page
• blog post - On Using Goss with docker healthchecks and Kubernetes

Why does this suck?

Because it's a quick hack I did over the weekend.. or I suck.. maybe both?

I tried to use it and got an error

Open an issue, create a pull request.. contribute :)

Why is the CLI parsing so bad?

See the last two questions.