Adam Hassick <ahassick@iol.unh.edu> writes:

> Updates the README with information on the added arguments
> and support for building OCI manifests.
>
> Signed-off-by: Adam Hassick <ahassick@iol.unh.edu>
> ---

I stopped reviewing.  The changes here introduce spelling mistakes and
spaces at the end of lines.  Please proofread it before making changes.

>  containers/README.md | 123 +++++++++++++++++++++++++++----------------
>  1 file changed, 77 insertions(+), 46 deletions(-)
>
> diff --git a/containers/README.md b/containers/README.md
> index 5d01caf..59edfcc 100644
> --- a/containers/README.md
> +++ b/containers/README.md
> @@ -14,73 +14,80 @@ nearly mandatory for this task.
> 
>  1. Licensed RHEL containers need podman
> 
> -The build system MUST be able to handle creating properly licensed RHEL
> -containers, so that the RHEL CI testing is as accurate as possible.
> +The build system MUST be able to handle creating properly licensed RHEL
> +containers, so that the RHEL CI testing is as accurate as possbile.

Why these lines changed?  Rather, I see that a space was added at the
end, and a spelling mistake was introduced s/possbile/possible/.  That
can't be intentional - please undo this change.

>  2. "Developer Laptop Friendliness"
> 
> -Another goal of the build system was to enable anyone to easily build the
> +Another goal of the build system was to enable anyone to easily build the
>  containers. Not all developers are able to use Linux as the main OS on their
>  main development machine. Podman runs on MacOS via podman-machine and Windows
> -either by podman-machine or WSL.
> +either by podman-machine or WSL.

Why were spaces added at the end in this section?  Please don't do that.

>  3. OCI Containers
> 
> -OCI containers are more portable than some other container solutions. Much of
> +OCI containers are more portable than some other container solutions. Much of
>  the progress on getting containers running on top of FreeBSD jails targets OCI
> -containers specifically. The tracking issue for this is
> +containers specifically. The tracking issue for this is
>  [https://reviews.freebsd.org/D21570](https://reviews.freebsd.org/D21570).
> -Once upstream support happens, there should be a relatively simple path to
> +Once upstream support happens, there should be a relatively simple path to
>  supporting containers in FreeBSD once podman/docker APIs are better supported.
> -At the moment, lack up upstream support means no support in this project for
> -FreeBSD.
> +At the moment, lack up upstream support means no support in this project for
> +FreeBSD. 
> 
>  ### Python and Makefiles instead of Buildah as a library
> 
> -The next question someone might have is why a combination of Python and
> +The next question someone might have is why a combination of Python and
>  makefiles were used instead of using buildah as a library. The largest
>  reason is that every DPDK developer is going to need to have some
> -level of familiarity with Python due to DTS. Buildah is only available
> -as a library via Go, and would tie DPDK to a particular container
> +level of familarity with Python due to DTS. Buildah is only avaliable

familiarity was correct.  available was correct.

> +as a library via Go, and would tie DPDK to a particular container
>  implementation. Go, while not difficult to learn, is a compiled language,
>  meaning that the build system would require a build system.
> 
> -The other reason is that most of the logic that needs to be performed is very
> -simple, and python has a few libraries that do most of the work. If it weren't
> -for the desire to have an inventory file (inventory.yaml) with a schema
> -(inventory_schema.json), this probably could have been an AWK script. After the
> -container images are produced, it is very easy to use the same template
> -engine to produce a makefile that can be used to both build and push the
> -containers. This makefile can be run with multiple jobs for parallel building
> -of containers, something not supported by all compose implementations.
> -
> -Meson was considered instead of Makefiles, however, Meson does not handle new
> -Meson being generated during the build very well, and Meson wants most commands
> -to have an output file, which is not true of many of the commands. Meson is
> -also more difficult to generate using a templating library than Makefile
> -targets.
> +The other reason is that most of the logic that needs to be performed is very
> +simple, and python has a few libraries that do most of the work. If it weren't
> +for the desire to have an inventory file (inventory.yaml) with a schema
> +(inventory_schema.json), this probably could have been an AWK script. After the
> +container images are produced, it is very easy to use the same templating
> +engine to produce a makefile that can be used to both build and push the
> +containers. This makefile can be run with multiple jobs for parallel building
> +of containers, something not supported by all compose implementations.
> +
> +Meson was considered instead of Makefiles, however, Meson does not handle new
> +Meson being generated during the build very well, and Meson wants most commands
> +to have an output file, which is not true of many of the commands. Meson is
> +also more difficult to generate using a templating library than Makefile
> +targets.
> 
>  ## Building
> 
>  ### Environment Variables
> 
> -All environment variables are namespaced to DPDK_CI_CONTAINERS to avoid any
> -issues.
> +All environment variables are namespaced to DPDK_CI_CONTAINERS to avoid any
> +issues.
> 
>  | Variable                   | Description                                     | Default | Valid Values |
>  | -------------------------- | ----------------------------------------------- | ------- | ------------ |
> -DPDK_CI_CONTAINERS_ON_RHEL | Whether you are building on licensed RHEL. RHEL containers must be built on licensed RHEL, this can be used to forcibly enable/disable RHEL containers if automatic detection fails. | (grep -q 'Red Hat Enterprise Linux' /etc/redhat-release && echo 'Y') \|\| echo 'N' | 'Y' or 'N'
> +| DPDK_CI_CONTAINERS_ON_RHEL | Whether you are building on licensed RHEL. RHEL containers must be built on licensed RHEL, this can be used to forcibly enable/disable RHEL containers if automatic detection fails. | (grep -q 'Red Hat Enterprise Linux' /etc/redhat-release && echo 'Y') \|\| echo 'N' | 'Y' or 'N'
>  DPDK_CI_CONTAINERS_FAIL_ON_UNBUILDABLE | Fail during dockerfile generation if any container in the inventory is not buildable. Currently will cause a failure if you are not on RHEL and try to build RHEL containers. | 'N' | 'Y' or 'N'
> +DPDK_CI_CONTAINERS_ONLY_HOST_ARCH | If set to 'Y', only images for the local system architecture will be built. | 'N' | 'Y' or 'N'
> +DPDK_CI_CONTAINERS_IS_BUILDER | If set to 'Y', disables the manifest features, and only builds images for the local system architecture. Intended to be set when used inside another orchestration sofware. | 'N' | 'Y' or 'N'
> +DPDK_CI_CONTAINERS_NINJA_WORKERS | The number of Ninja workers to use to build ABI images. Variable setting is benign if ABI is disabled. | unset | Any positive integer greater than zero.
>  DPDK_CI_CONTAINERS_BUILD_ABI | Whether to bake ABI images into the containers. | 'N' | 'Y' or 'N'
> -DPDK_CI_CONTAINERS_BUILD_LIBABIGAIL | Whether to build libabigail from source on distros that do not package it. DPDK_CI_CONTAINERS_BUILD_ABI=Y overrides this to 'Y' | 'N' | 'Y' or 'N'
> +DPDK_CI_CONTAINERS_NO_LATEST_TAG | Disables tagging the final manifests as "latest" in the local store and remote registry. | 'N' | 'Y' or 'N'
> +DPDK_CI_CONTAINERS_COVERITY | Enable building Coverity images. Setting this flag will make the Coverity binaries required. | 'N' | 'Y' or 'N'
>  DPDK_CI_CONTAINER_BUILDER_PROGRAM | What container builder program to use. | 'podman' | Any container builder that exposes the same interface and provides the same behavior as podman.
> -DPDK_CI_CONTAINERS_LIBABIGAIL_CLONE_URL | What URL to clone libabigail from, since some distros need to compile it from source. | 'git://sourceware.org/git/libabigail.git' | A repository containing libabigail which shares history with the main repository.
> +DPDK_CI_CONTAINERS_LIBABIGAIL_CLONE_URL | What URL to clone libabigail from, since some distros need to compile it from source. | 'git://sourceware.org/git/libabigail.git' | A repository containing libabigail which shares history with the main repository.
>  DPDK_CI_CONTAINERS_DPDK_CLONE_URL | What URL to clone DPDK from. | 'https://dpdk.org/git/dpdk' | Any DPDK mirror.
> +DPDK_CI_CONTAINERS_DPDK_STABLE_CLONE_URL | What URL to clone DPDK stable form. | http://dpdk.org/git/dpdk-stable | Any DPDK stable mirror.
>  DPDK_CI_CONTAINERS_CONTAINER_BUILDER_TAG | What tag to give to the container which creates the dockerfiles. The default should be fine unless you have issues with collisions. | 'dpdk_ci_container_builder' | Any valid OCI container tag (A valid C function name will work)
>  DPDK_CI_CONTAINERS_EXTRA_PUSH_ARGS | Extra arguments to add to the push command, can be used for credentials if 'podman login' won't work. | '' | [https://docs.podman.io/en/latest/markdown/podman-push.1.html#options](https://docs.podman.io/en/latest/markdown/podman-push.1.html#options)
>  DPDK_CI_CONTAINERS_REGISTRY_HOSTNAME | The hostname of the registry to push to. | 'localhost' | The hostname of any system exposing an OCI container registry or localhost to push to local storage.
>  DPDK_CI_CONTAINERS_EXTRA_SCRIPTS_PATH | The path to a directory to copy into all of the containers at /scripts | unset | The path to any local file directory.
> +DPDK_CI_CONTAINERS_COVERITY_PATH | The path to Coverity Scan binaries. Only required of the Coverity flag is set. | unset | The path to any local file directory.
>  DPDK_CI_CONTAINERS_CONTEXT_DIRECTORY | Set the directory to build the containers in. All generated files will be placed in this directory or one of it's children | '$(CURDIR)/container_context' | Any absolute directory path
> +DPDK_CI_CONTAINERS_DATE_TAG_OVERRIDE | Uses a provided string instead of generating a new date tag. Intended for development use. | unset | Any string that is a valid OCI manifest tag.
> 
>  ### Builder System Requirements
> 
> @@ -91,16 +98,15 @@ DPDK_CI_CONTAINERS_CONTEXT_DIRECTORY | Set the directory to build the containers
>  * find
>  * posix utilities (GNU coreutils will work)
>  * bash
> -* podman >= 4.0.0 (docker or other container builder programs may work, but are
> -unsupported)
> -    * podman 4.0.0 allows run mounts, which allow mounting a directory into the build context of a container. This is used to  persist ccache directories for each container.
> -* qemu-$ARCH-static for any non-native architecture/revision you want to build for.
> +* podman (docker is unsupported, and will NOT work for making manifests)
> +* qemu-$ARCH-static for any non-native architecture/revision you want to build
> +for.
> 
>  #### Hardware
> 
> -| Hardware Type | Requirement                  | Reason |
> -| ------------- | ---------------------------- | ----------------------------------- |
> -| Disk space    | 5 GB of disk space per image | Some images are 4 GB at the moment, and as DPDK's API grows, so will the ABI references.
> +| Hardware Type | Requirement                   | Reason |
> +| ------------- | ----------------------------- | ----------------------------------- |
> +| Disk space    | 10 GB of disk space per image | Many of the final images are 4 GB at the moment, and as DPDK's API grows, so will the ABI references. Intermediate images generated by the builds will consume some additional space that is recoverable after the build.
>  Memory | Either 1.5x or 2x the memory needed to compile DPDK per makefile job | 1.5x is enough for the container overhead and caching when compiling natively, 2x is for builds under emulation (ARM container on x86, etc).
> 
> 
> @@ -111,28 +117,53 @@ RHEL container images must be built on RHEL.
>  ### Build containers locally
> 
>  ```bash
> +# Build using the default arguments
>  make build
>  ```
> 
> +The resulting images will be tagged based on the date tag and platform.
> +Image generated tags follow this format: `image-{{ platform }}-{{ date_tag }}`
> +Where `platform` denotes the platform of the image, and `date_tag` is the generated date tag or the override string provided
> +through the environment variable.
> +
> +They should appear in the local image store on your system.
> +
>  ### Push containers to registry
> 
> -This will probably involve following prompts in your terminal, but if you have
> -other authentication set up, (LDAP, Kerberos, etc), it may not prompt you.
> +This will probably involve following prompts in your terminal, but if you have
> +other authentication set up, (LDAP, Kerberos, etc), it may not prompt you.
>  Logging into a registry is what allows you to upload containers to a remote
> -system for others to pull down.
> +system for others to pull down.
> 
>  If you are working alone, you probably can ignore this and keep the containers
> -locally. If you are in an enterprise setting, ask your DevOps or Systems
> -Administration team where the preferred location for hosting containers is.
> +locally. If you are in an enterprise setting, ask your DevOps or Systems
> +Administration team where the preferred location for hosting containers is.
> 
> -Since these images take so long to build, it is recommended to use a container
> +Since these images take so long to build, it is recommended to use a container
>  registry and have any CI systems pull from that registry.
> 
> -Redhat guide to setting up a podman container registry:
> +Redhat guide to setting up a podman container registry:
>  [https://www.redhat.com/sysadmin/simple-container-registry](https://www.redhat.com/sysadmin/simple-container-registry)
> 
>  ```bash
>  $DPDK_CI_CONTAINER_BUILDER_PROGRAM login $DPDK_CI_CONTAINERS_REGISTRY_HOSTNAME
>  # < Complete login process >
>  make push
> -```
> \ No newline at end of file
> +```
> +
> +#### Manifests
> +
> +OCI manifests allow the grouping of images for different platforms under the same tag in a repository on a registry.
> +The use of OCI manifests over tagged images reduces the amount of system platform related branching in CI scripting.
> +
> +The Makefile provides the option to push only the images, only the manifests, or push the images and make manifests.
> +The default "push" target will perform the last case.
> +If you choose to create the manifests, then these will be created with the "final" tags like "latest" and the date timestamp.
> +
> +Manifest creation is known to not be compatible with Docker.
> +This feature is known to work when using Podman to post content to a Docker v2 registry.
> +
> +The manifests may be created on the registry independently of the image builds using the `push_manifests` target in place of the `push` target.
> +In contrast, the `push_images` target will only push the images and not create the manifests.
> +
> +If the `DPDK_CI_CONTAINERS_IS_BUILDER` variable is set to 'Y', then the `push_manifests` target will be disabled.
> \ No newline at end of file