Hatchup

Simple meetup.com clone

Author: Stephen "TheCodeAssassin" Hoogendijk

How to install

Testing/Development

Local testing will be done using Vagrant. Vagrant will spin up a machine (either locally or remotely) and use that instance to serve your code.

Note You need at least Vagrant 1.8.1

$ vagrant up

To deploy the application stack to AWS

The infra

First you would have to install Terraform and Ansible.

• Terraform: https://terraform.io/downloads.html
• Ansible: http://docs.ansible.com/ansible/intro_installation.html

You need to have a config.tf file so that Terraform can connect to your AWS account. Copy the config.tf.example file and replace the access_key and secret_key values.

You need to provide a public key name and the path to your a local public key. Important: The key needs to already be present in AWS EC2.

Obviously you need to replace "hatchup" with your own key name and path. I created a script to make it easier to interact with terraform.

Note This step might include the consumption of coffee/tea since it WILL take a while.

The script will create the infrastructure in AWS when running the apply operation.

# now apply the infrastructure
$ bash terraform/run.sh apply stephen ~/.ssh/stephen.pub

Provision

Provisioning is done with Ansible and can be simply called by running the ansible script included in the root directory.

$ ./ansible.sh

Destroying the infrastructure

Should you need to destroy all the managed infrastructure (this is considered catastrophic in a live scenario). You need to run the same script as above but using the destroy operation.

$ ./terraform.sh destroy stephen ~/.ssh/stephen.pub

What i would do to improve this

• Not put everything in one repo but separate it properly and on a self-hosted Gitlab or Stash
• Add more features of course
• Maybe use ElasticSearch Shield for additional security should the VPC be breached
• Improve ansible playbooks
• Installing the application via a CI instead of copy with ansible
• Write unit tests for the application

Why did i pick these technologies?

• PHP because i have the most experience with it (scripting language wise)
• Ansible because it's simple and gets the job done quickly
• Terraform because it allows me to scale easily

I did not like the prospect of storing users in Elasticsearch because i do not believe users belong there. If this would not be a simple MVP i would setup a proper MariaDB Galera cluster to host additional database requirements.

Does it scale?

Sure, just add nodes in the main.tf file. The EBS should take care of routing the traffic to healthy instances should your instance go down. Then re-run ansible to provision everything.

To scale up the web instances: Edit "count = x" in the terraform/web-nodes.tf file.

Infrastructure build

The following infrastructure will be build by the terraform configuration:

• A VPC with a gateway and 2 subnets (one per availability zone)
• 2 ELB Loadbalancers (one for the application and one for the elasticsearch cluster)
• 2 Elasticsearch instances (configurable)
• 2 Application instances (configurable)
• VPC Security group (for allowing traffic within the VPC)
• Security group for the Elasticsearch cluster
• Security group for the application cluster

Monitoring?

What about security?

We create a VPC which only exposes port 80 and port 22 to the outside. The elasticsearch nodes are not reachable via the Internet only from instances inside the VPC.