Yaml Introduction

This notes is for the course Kuberenetes for absolute beginners

Yaml introduction

According to yaml.org, “YAML is a human-friendly, data serialization standard for all programming languages."
Yaml is used to create kubernetes configurations

Structure of YAML file

Key Value Pair

The basic type of entry in a YAML file is of a key value pair. After the Key and colon there is a space and then the value.

Fruit: Apple
Vegetable: Radish
Liquid: Water

Array/List

Lists would have a name and a number of items listed under it. The elements of the list would start with a -. There can be a n of lists, however the indentation of various elements of the array matters a lot.

Fruits:
  - Orange
  - Banana
  - Mango
Vegetables:
  - Potato
  - Tomato
  - Carrot

Dictionary/Map

A more complex type of YAML file would be a Dictionary/Map.

Banana:
  Calories: 200
  Fat: 0.5g
  Carbs: 30g
Grapes:
  Calories: 100
  Fat: 0.4g
  Carbs: 20g

It is important to indent Yaml properly. Improper indentation would break a sibling / parent relationship between the properties.

Advanced YAML structures

List containing a list of dictionaries.

- Fruits:
    - Banana:
        Calories: 105
        Fat: 0.4g
        Carbs:  27g
    - Grape:
        Calories: 62
        Fat: 0.3g
        Carbs:  16g
- Vegetables:
    - Potato:
        Calories: 105
        Fat: 0.4g
        Carbs:  27g

Dictionary in Dictionary

Banana:
  type:
    name: musa
  Calories: 200
  Fat: 0.5g
  Carbs: 30g

A list is ordered
A dictionary is unordered

Yaml Introduction