constellation/3rdparty/coreos-assembler/HACKING.md

dm-verity patch for CoreOS assembler

Constellation uses CoreOS as a base for OS images. While the images are mostly unmodified and can be built using the upstream CoreOS assembler, small modifications to the assembler are required to support dm-verity for the root filesystem.

Checkout the CoreOS assembler source code from the upstream repo using the commit ID specified in the Makefile

make clone

Apply the patch:

make patch

Now you can make changes to the coreos-assembler and compile it using the included Dockerfile:

make containerimage

Once you are done, create a new patch file (within 3rdparty/coreos-assembler/build/coreos-assembler):

git diff HEAD^ > ../../verity.patch

Building the CoreOS assembler container image

make

The resulting container image will be tagged as localhost/coreos-assembler.