54 dockercontainer 55 name containername 56 state

54
docker_container:
55
name: '{{ container_name }}'
56
state: absent
The post-tasks clean up unnecessary cruft inside the container (trimming down the
size of the committed image), commit the Docker container to an image (tagged
a4d/hubot-slack:latest
), and remove the running container.

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415
When building from a
Dockerfile
, you can set things like the
USER
(the user used to
run the
CMD
or
ENTRYPOINT
in the container) and
CMD
(the defaults for an executing
container) directly. In our case, since we’re not building from a
Dockerfile
, we set
these options using
docker commit
’s
-c
or
--change
option.
Now that we have the main scaffolding in place for building a Docker container,
committing an image from that container, and tearing down the container, it’s time
to add the ‘meat’ to our playbook—the role that installs Hubot and its Slack adapter.
Building the
hubot-slack
role
As with any role, the easiest way to scaffold the necessary files is using the
ansible-galaxy
command. Create a
hubot-slack
role in a
roles
subdirectory with:
ansible-galaxy role init hubot-slack
You can delete some unneeded role directories, namely
files
,
handlers
,
templates
,
tests
, and
vars
. If you want, fill in the metadata fields inside
meta/main.yml
(this is
only needed if you’re publishing the role on Ansible Galaxy or if you need to have
other roles defined as dependencies, though).
Since Hubot isn’t too hard to install, we can do everything we need inside
tasks/main.yml
.
The first thing we need to do is ensure all the required dependencies for generating
our bot are present:
1
---
2
- name: Install dependencies.
3
package:
4
name: sudo
5
state: present
6
7
- name: Install required Node.js packages.
8
npm:
9
name: "{{ item }}"
10
state: present
11
global: yes
12
with_items:

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416
13
- yo
14
- generator-hubot
Because we want to be able to run certain commands as a
hubot
user later, we’ll need
sudo
present so Ansible can
become
the
hubot
user. Then we’ll install some require
dependencies—
yo
and
generator-hubot
, which are used to build the bot. Node.js is
already present inside the container, since we chose to build the container based off
the
node:8
base image.
16
- name: Ensure hubot user exists.
17
user:
18
name: hubot
19
create_home: yes
20
home: "{{ hubot_home }}"
It’s best to run Hubot inside an isolated directory, using a dedicated user account, so
we set up a
hubot
user account with its own home directory. To make the Hubot role
easier to adapt, a variable is used for the
hubot
user’s home directory. We’ll define
that later in
defaults/main.yml
.
22
- name: Generate hubot.
23
command: >
24
yo hubot
25
--owner="{{ hubot_owner }}"
26
--name="{{ hubot_name }}"
27
--description="{{ hubot_description }}"
28
--adapter=slack
29
--defaults
30
chdir={{ hubot_home }}
31
become: yes
32
become_user: hubot
The
yo hubot
command scaffolds all the code necessary to run Hubot, and all the
options passed in tell the generator to run non-interactively. We will define the
default role
hubot_
vars in this command later in
defaults/main.yml
.

Chapter 15 - Docker and Ansible
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34
- name: Remove certain scripts from external-scripts.json.