1eb5c60 Oct 14, 2015
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@penberg @VincentS @asias
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The Capstanfile is a YAML config file for specifying Capstan images.

An minimal file looks as follows:

base: cloudius/osv-base

cmdline: /tools/

build: make


base specifies the base image that is amended with files use capstan search (remote images) or capstan images (local images) for a list of available images.

cmdline is the startup command line passed to OSv.

build specifies an optional build command.

files is a map of files that are amended to the base image. The left side specifies the full path of the file as it will appear in the image and the right side specifies a relative path to current directory of the actual file that is added to the image.

File mapping supports basename variable substitution with the "&" character. You can specify this:

  /usr/app/app.jar: build/&

which expands to the following during build:

  /usr/app/app.jar: build/app.jar

Here /usr/app/app.jar is the path in the built image and build/app.jar is the file that is picked up from the local filesystem.

rootfs specifies a directory that is amended to the base image. The directory hierarchy in the base image will be the same as in the rootfs directory. If rootfs is not specified in Capstanfile, a default rootfs directory named ROOTFS will be used. If both files and rootfs are specified, both will be used to amended the base image.

RPM support

Capstan also supports installing RPMs with the rpm-base option:

  name: java-1.7.0-openjdk
  arch: x86_64