HRM - Hardware Resource Manager

Daemon for optimal EC2 resources utilization.

Provides API and conventions for background jobs to be performed on dedicated EC2 instance while keeping it's utilization as low as possible.

It performs smart starting and stopping instances based on scheduled jobs.

API

POST /tasks — enqueue job. Params:

• action_url — Required. URL of the job worker. It should start job upon request and keep connection until completion;
• callback_url — Optional. URL to call back upon completion or error;
• instance_id — Optional. EC2 Instance ID to start/stop;
• access_key_id, access_key_secret — Required if instance_id specified. Access Key for that instance.
• timeout — Optional. action_url request timeout in seconds. Default to 30 minutes.

Returns ID to identify that job later.

Use {dns_name} or {private_dns_name} as a part of action_url to use real instance hostname, i.e. http://{private_dns_name}/my_action_url

GET /tasks/:id — check job status.

Returns JSON representation of job params, including status and meta (see below).

PUT /tasks/:id — update job meta. Params:

• meta — Any information worker may want to report. It's intended mainly for progress information.

DELETE /tasks/:id — delete job.

Just in case :)

GET /status — check status of all managed jobs and instances.

Returns JSON with:

• controlled_instances array – instances started by HRM and scheduled for stopping
• pending_tasks hash {"task id": "instance id"} — tasks that are running currently.

Other details

• Additional param hrm_task_id is being added to action_url query string for job worker to know how to update meta.
• Additional param hrm_task_id is being added to callback_url query string for client to know which job is done.
• hrm_task param contains same JSON data as GET /tasks/:id result
• HTTP port could be changed in dev.config

Usage

• Install Erlang R15B+ for your system

• Checkout this repo

• ./rebar get-deps

• make

• ./start to start it as daemon

• make shell to start it interactively

Todo

• wipe access_key_id and access_key_secret when it's not needed anymore
• some way to get monit (or some other monitoring tool) play well with daemon