Application Format

Gravity application is a tarball, i.e. any .tar.gz file. The file has the following structure:

app.tar.gz
  ├── registry
  │   └── docker
  │       └── registry
  │           └── v2 ...
  │           ... 
  └── resources
      ├── app.yaml
      └── skydns.yaml

Only the registry and resources directories are mandatory, the rest is application-specific.

In this example:

1. registry stores docker image layers in the registry v2 format. See assets/dns-app/Makefile to get an understanding about how it is produced.
2. resources contains the application manifest.

The rest is application-specific.