To build and push Docker image with the server, you need to issue the following commands while being in repo's root directory:
docker login
docker build --tag astrosmash/sre-challenge --file docker/Dockerfile .
docker push astrosmash/sre-challenge
I've already built and pushed the image to docker hub, so we can use it further: https://hub.docker.com/r/astrosmash/sre-challenge/tags/
Then you will need to fill some info into terraform.tfvars:
{access,secret}_key for AWS api
deployer_key is your ssh public key
Also change default deployer_private_key_path location in variables.tf.
To provision the server to the AWS infra, you will need the following commands:
terraform init - to create initial state
terraform plan - to check what's going to be created
terraform apply - to actually propagate the changes
This will create t2.micro instance with latest Ubuntu ami, configure docker host on it, and run the container with the server. Log provider for the container will be awslogs, so it will send its stdout into Cloudwatch. Then you can see server's output in CloudWatch Log > Groups > docker-logs > sre-challenge. Cloudwatch metric is also assigned as a filter to this log group, so when it discrovers 'error' pattern in the log, it will trigger an alarm.
The server listens on INADDR_ANY, so you can just echo -n '[17/06/2016 12:30] Time to leave' | nc ip.add.re.ss 1234
The only thing that doesn't work is auto-subscription of an email to the SNS topic, as described here: https://www.terraform.io/docs/providers/aws/r/sns_topic_subscription.html#email
To receive alert emails, you need to change the topic manually: SNS > Topics > docker_cloudwatch_notifications > Subscribe to topic > Protocol: Email, Endpoint: your@email.com.