YAML (YAML Ain't Markup Language)

Key-Value pair in YAML:

"apple" : "I am a red fruit"
1 : "This is kunal roll number"

{mango: "yellow fruit", age : 23}

List in YAML :

- apple
- banana
- cherry
- mango

cities:
 - new delhi
 - mumbai
 - gujrat

cities: [new delhi, mumbai]

"apple" : "I am a red fruit"
1 : "This is kunal roll number"
---
- apple
- banana
- cherry
- mango
---
cities:
 - new delhi
 - mumbai
 - gujrat
 ...

(---) You can see in the above program we can use --- to tell yaml that this are three different documents.

(...) You can use this to stop your yaml file

Data Type in YAML:

String Data Type:


domain: DevOps
fruit : "mango"
job : 'Software engineer'

Interger, Float,Boolean Data Type:

numbers: 5473
marks: 98.74
booleanvalue: No # n , N , false , FALSE
booleanvalue: yes # y , Y , true , TRUE

Sparse Sequence DataType:

sparse seq:
- hey
- how
-
- are you
- rutuja

Nested Sequences:

-
 - mango
 - cherry
 - banana
-
 - marks
 - roll no
 - dates

Ansible playbook example:

---
- name: Install and Start Nginx
  hosts: webservers
  become: true
  tasks:
    - name: Install Nginx package
      apt:
        name: nginx
        state: present

    - name: Start Nginx service
      service:
        name: nginx
        state: started
        enabled: yes

ansible-playbook -i inventory.ini playbook.yml

n this playbook:

The play is named "Install and Start Nginx" and targets the hosts in the webservers group.
The become: true statement allows the playbook to run with escalated privileges.
Two tasks are defined:
- The first task uses the apt module to install the Nginx package, specifying the package name (nginx) and the desired state (present).
- The second task uses the service module to start the Nginx service, ensuring it is running and enabled to start at boot (enabled: yes).