rimusz-lab / deis-backing-services

Backing Services API for student cloud

Deis Backing Services Manager

At Codaisseur we wanted to provide a Heroku like environment for students. We <3 Deis Workflow as do our students, as you can see in this picture.

Anyway..

We use Rails a lot, and PostgreSQL, so we needed an easy way for students to set up their apps despite the fact that Deis does not provide a PostgreSQL service for them like Heroku does. This manager app takes care of that.

Prerequisites

• A working Deis workflow cluster on k8s
• Helm classic installed and set up
• Deis client installed and set up

Install a Redis cluster with Helm

We'll use Helm to set up a HA Redis cluster for us. Refer to the Helm docs for install instructions.

helmc install redis-cluster

Set up the Postgres service cluster and MongoDB data disk

Check out the instructions to set up the services cluster on Kubernetes to get you started.

Install MongoDB

helmc repo add bitnami https://github.com/bitnami/charts
helmc fetch bitnami/mongodb
helmc edit mongodb

Update tpl/values.toml to match your needs.

Then run the generators:

helmc generate --force mongodb

And install:

helmc install mongodb

Installing Memcached

Fetch the memcached chart with helmc

helmc fetch memcached

Then make it a little easier to use by adding 2 services

helmc edit memcached

# manifests/memcached-rc.yaml

apiVersion: v1
kind: Service
metadata:
  name: memcached-1
spec:
  ports:
  - name: memcached-port-1
    port: 11211
    protocol: TCP
    targetPort: 11211
  selector:
    app: memcached-1

---

apiVersion: v1
kind: Service
metadata:
  name: memcached-2
spec:
  ports:
  - name: memcached-port-2
    port: 11211
    protocol: TCP
    targetPort: 11211
  selector:
    app: memcached-2

---

apiVersion: v1
kind: ReplicationController
metadata:
  name: memcached-1
  labels:
    app: memcached-1
    heritage: helm
spec:
  replicas: 1
  selector:
    name: memcached-1
    mode: cluster
    provider: memcached
  template:
    metadata:
      labels:
        name: memcached-1
        mode: cluster
        provider: memcached
    spec:
      containers:
      - name: memcached
        image: "memcached:1.4.24"
        ports:
        - containerPort: 11211
---
apiVersion: v1
kind: ReplicationController
metadata:
  name: memcached-2
  labels:
    heritage: helm
    app: memcached-2
spec:
  replicas: 1
  selector:
    name: memcached-2
    mode: cluster
    provider: memcached
  template:
    metadata:
      labels:
        name: memcached-2
        mode: cluster
        provider: memcached
    spec:
      containers:
      - name: memcached
        image: "memcached:1.4.24"
        ports:
        - containerPort: 11211

Then install it

helmc install memcached

---

apiVersion: v1

Setting up the Manager App

Create a Deis app

Clone this repository and set up a deis app:

deis create

Get the proxy service ip

kubectl get svc

NAME                   CLUSTER-IP       EXTERNAL-IP   PORT(S)
memcached-1            10.115.249.176   <none>        11211/TCP
memcached-2            10.115.244.86    <none>        11211/TCP
mongodb                10.115.240.18    <none>        27017/TCP
redis-sentinel         10.115.253.131   <none>        26379/TCP
stolon-proxy-service   10.115.246.38    <none>        5432/TCP

Deploy the Backing Services Manager App

The app runs from a Docker container, and you will need to set a SECRET_KEY_BASE:

deis config:set SECRET_KEY_BASE=$(rails secret)

Use the IP to create the DATABASE_URL, we will use the one mentioned in the above output:

deis config:set DATABASE_URL=postgresql://stolon:password@10.115.246.38:5432/backing_services

And same for REDIS_URL:

deis config:set REDIS_URL=redis://10.115.253.131:26379/redis_services

Then the 2 MEMCACHED_SERVERS separated by commas:

deis config:set MEMCACHED_SERVERS=10.115.249.176,10.115.244.86

And finally MONGODB_URL:

deis config:set MONGODB_URL=mongodb://root:rootPassword@10.115.240.18:27017/admin

Use the root user and root password from the values.toml file that you edited with helmc.

Then deploy the Rails app:

git push deis master

And run the rake task to create the backing_services database for this app:

deis run rake deis:create_database

Then migrate the database:

deis run rake db:migrate

Get a Postgres database for new Apps

When you are setting up a new app that needs to use PostgreSQL, you can create a database by POSTing to the Manager app's Postgres endpoint:

curl -XPOST http://watery-fowls.xxx.xxx.xx.xxx.nip.io/postgres_databases

This will return your new DATABASE_URL:

DATABASE_URL=postgres://meagan:[e-mail]:5432/compress_program

Get a Redis db for new Apps

Similarly, we can get a REDIS_URL for new apps:

curl -XPOST http://watery-fowls.xxx.xxx.xx.xxx.nip.io/redis_services

Which will return something like:

REDIS_URL=redis://10.xxx.xxx.xx:26379/copy_port

Get a Mongo db for new Apps

And unsurprisingly this works the same for MongoDB:

curl -XPOST http://watery-fowls.xxx.xxx.xx.xxx.nip.io/mongodb_services

Which will return something like:

MONGODB_URL=mongodb://10.xxx.xxx.xx:27017/persistence_much

Get a Memcached namespace for new Apps

Memcached is configured with servers and a namespace:

curl -XPOST http://watery-fowls.xxx.xxx.xx.xxx.nip.io/memcached_services

Which will return something like:

MEMCACHED_SERVERS=10.115.244.86,10.115.249.176 MEMCACHED_NAMESPACE=navigate_card

Roadmap

• We will add more services as we go, like:
  • √ PostgreSQL
  • √ Redis
  • √ MongoDB
  • √ Memcached
• Create a Helm chart for Stolon.
• Create Helm charts for the entire cluster

Let us know which services you are missing and we will try to add them.

Feel free to help us out or leave any feedback in the issues :)

Changelog

• 2016-07-26 Initial project with PostgreSQL service
• 2016-07-31 Added Redis, MongoDB, and Memcached services
• 2016-08-08 Fixed MongoDB issues, running from Dockerfile now

Thanks to

• The Deis Team for the awesomeness that is our own PaaS!
• The Bitnami team for their awesome list of helmc charts
• The Storint.lab team for their super duper HA Postgres solution Stolon