Sequenc

Sequenc is a Node.js application dedicated to run jobs that take long to execute. Whether you need to convert a video or crawl handful of webpages and expect results to arrive later Sequenc to the rescue!

Currently website capture and conversion process which uses PhantomJs and ffmpeg is the only job processor that is implemented. It can capture arbitary url as a static image or video.

Installing

Requirements

• Node.js >= 0.10.0
• Phantomjs >= 1.9.2
• ffmpeg
• AWS S3 credentials and bucket to store job results

Dev requirements

• Grunt

Local setup

• npm install to install package dependancies
• Sequenc expects to find exported AWS_ACCESS_KEY_ID, AWS_ACCESS_SECRET_KEY, AWS_S3_BUCKET env variables in order to upload job results to S3
• node index.js to start the app or grunt server to run it via nodemon

Heroku setup

• Create an app on heroku
• git remote add heroku https://yourapp.herokuapp...
• This app uses .buildpacks file to get all dependacies on heroku, add buildpack-multi to your app: heroku config:add BUILDPACK_URL=https://github.com/ddollar/heroku-buildpack-multi.git
• Set all required env variables on heroku like heroku config:set NODE_ENV=production
• git push heroku master to deploy

Using

Procs

Processes to digest your jobs lie in ./procs/. More info to come...

REST JSON API

POST /jobs

Create a job:

$ curl -H "Content-Type: application/json" -X POST -d \
  '{
    "uri": "http://mashable.com",
    "type": "capture",
    "height": 1200,
    "duration": 3,
    "format": "gif"
  }' http://localhost:3000/jobs

Response:

{
  "state": "inactive",
  "message": "job accepted",
  "id": 1,
  "_links": [
      {
          "self": {
              "href": "http://localhost:3000/jobs/1"
          }
      }
  ]
}

Querying "self" link will get you status of the job:

{
  "id": "1",
  "type": "capture",
  "input": {
      "uri": "http://mashable.com",
      "type": "capture",
      "height": 1200,
      "duration": 3,
      "format": "gif"
  },
  "priority": 0,
  "progress": "12",
  "state": "active",
  "created_at": "1379954952350",
  "updated_at": "1379954955490",
  "attempts": {
      "remaining": null
  }
}

Once job is complete it will redirect you to /jobs/:id/output which will attempt to serve job results (from file locally or via redirect to a file stored on S3)