can I embed inventory inside the playbook?

I want to have build some minimal example for ansible playbook, thus I do not want to have multiple files and dirs for each playbook.

I would like to make the single file contain everything.

I knew I can use localhost like following, then I can just run the playbook without inventory.

- name: Example playbook
  hosts: localhost
  connections: local
  tasks:
    - ansible.builtin.debug: "hello!"

I wonder how can I do similar thing but also define a simple inventory inside the playbook:

all:
  hosts:
    localhost:
      ansible_connection: local
    host1:
      http_port: 80
      maxRequestsPerChild: 808
      ansible_host: 127.0.0.2

the hosts keyword in the playbook seems only accept list of strings

Solution

You cannot "embed" an inventory in the playbook, but you could dynamically build an inventory using the add_host module.

E.g:

- hosts: localhost
  gather_facts: false
  tasks:
  - add_host:
      name: newhost1
      groups:
      - webservers
      http_port: 80
      maxRequestsPerChild: 808
      ansible_host: 127.0.0.2

- hosts: webservers
  gather_facts: false
  tasks:
  - ping:

Running this produces:

PLAY [localhost] ***************************************************************

TASK [add_host] ****************************************************************
changed: [localhost]

PLAY [webservers] **************************************************************

TASK [ping] ********************************************************************
ok: [newhost1]

PLAY RECAP *********************************************************************
localhost                  : ok=1    changed=1    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0   
newhost1                   : ok=1    changed=0    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0