PrgCont - Ansible and Buildah will 🎸 your containers

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# Ansible and Buildah will 🎸 your containers
## Tomas Tomecek

---

# `/who Tomáš Tomeček`

* Principal Software Engineer @ Red Hat

* Team lead

* RHEL and Fedora

* Containers, automation and integration

* I ❤ open source

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.left-column[
# What's Ansible?
* Automation tool.

* Definition language.

* Can provision infrastructure.
]
.right-column[
```
---
- hosts: localhost
  vars:
    project_dir: /src
  tasks:
  - name: Install required packages
    dnf:
      name:
      - git
      - python3-pytest
      - python3-flexmock
  - name: copy entrypoint script
    copy:
      src: contrib/entry.sh
      dest: /entry.sh
  - name: Install the library
    pip:
      name: '{{ project_dir }}'
```
]

---
# What's Buildah?

* Can build container images from dockerfiles.

* Or from scratch.

* Or you can script the build process yourself.

----

```
$ buildah bud .
STEP 1: FROM busybox
STEP 2: RUN ls
total 16K
bin dev etc home proc root sys tmp usr var
STEP 3: COPY ./README.md /
STEP 4: CMD /entrypoint.sh
```

---

# How they work together?

* Ansible connection plugins.

```
$ ansible-playbook -vvvvvv -c buildah ...
TASK [Gathering Facts] ***************************************************
<buildah-container> RUN [b'buildah', b'mount', b'--', b'buildah-container']
MOUNTPOINT b'/var/lib/containers/storage/overlay/89e0b96a0fa4651a87e7931...
<buildah-container> RUN [b'buildah', b'run', b'--', b'buildah-container', \
 b'/bin/sh', b'-c', b'( umask 77 && mkdir -p "` echo / tmp/ansible-tmp-\
 1547462832.3904593-53681476701867 `" && echo ansible-tmp-1547462832...
<buildah-container> PUT /root/.ansible/tmp/ansible-local-\
<buildah-container> RUN [b'buildah', b'run', b'--', b'buildah-container', \
...
<buildah-container> RUN [b'buildah', b'umount', b'--', b'buildah-container']
```

???

* Describe a connection plugin
* List common plugins
* Describe the output above

---

# Let's give it a shot

```
$ buildah pull $BASE_IMAGE

$ buildah from --name $CONT_NAME $BASE_IMAGE

$ printf "$CONT_NAME \
    ansible_connection=buildah \
    ansible_python_interpreter=/usr/bin/python3" >inventory-container

$ ansible-playbook -i inventory-container -c buildah ./recipe.yaml

$ buildah commit --cmd '/entrypoint.sh' $CONT_NAME my-fancy-image

$ buildah rm $(CONT_NAME)
```

???

* We use this!
* Do it for realz

---
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# Someone could automate that script

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# ansible-bender

* [github.com/ansible-community/ansible-bender](https://github.com/ansible-community/ansible-bender)

* Bends containers. And it's shiny.

* Ansible playbooks define the container image content.

* Image metadata as Ansible vars.

* Builds as first-class citizens.

* Can move images to registry, file, dockerd...

* Configurable layering and caching.

???

* It's not perfect, still a ton of work ahead.

* rootless + ovl doesn't work

* RFE: define build metadata in a file

---

# Why should you care?

* Ansible has powerful modules.

* Ansible is built on top of jinja2.

* You can recycle your playbooks and roles.

* Dockerfiles have no formal specification.

* You can only use Dockerfiles to build ~~docker~~ container images.

* [There](https://www.youtube.com/watch?v=n9-JTUsAK9Y) were [no improvements](https://www.youtube.com/watch?v=3VZsjv217ow) for years.

* Finally there is Buildkit now.

* Build the way you want.

???

* I'm not a docker hater.

---

# Plans

* Work on [0.6.0](https://github.com/ansible-community/ansible-bender/milestone/2).

* Move it to Github Ansible organization. ✓

---
# Plans (cont'd)

* It may also get renamed.

![Bender is sad.](sad-bender.jpg)

---

# Thank you!

* [github.com/TomasTomecek/speaks](https://github.com/TomasTomecek/speaks)

* [github.com/ansible-community/ansible-bender](https://github.com/ansible-community/ansible-bender)

* [@TomasTomec](https://twitter.com/TomasTomec)

* [blog.tomecek.net](https://blog.tomecek.net/)