Introduction to YAML

CI/CD for Machine Learning

Ravi Bhadauria

Machine Learning Engineer

What is YAML?

YAML: YAML Ain't Markup Language
Used in configuration files, data exchange, and structured data representation
A data formatting language similar to JSON and XML
Allows a standard format to transfer data between languages or applications
Simple and clean format
Valid file extensions: .yaml or .yml
Used to write configuration for variety of CI/CD tools:
- GitHub Actions
- Data Version Control (DVC)

YAML Syntax

YAML has a hierarchical structure
- Indentation is meaningful
Tabs are not allowed
YAML validators (https://www.yamllint.com/)
Comments start with #

name: Ravi
occupation: Instructor
# This is a valid comment
programming_languages: # and this one too
  python: Advanced
  go: Intermediate
  scala: Beginner

YAML Scalars

Numbers: Integers or floating-point numbers
Booleans: true or false
Null: keyword null or ~
Strings: Represented as plain text or enclosed in '' or ""

# Integer
42
# Floating point
3.14

# Boolean
true

# Null values
null

# String value
a: "A string in YAML"
b: 'A string in YAML'
c: A string in YAML

YAML Collections

Sequences

Also called lists, arrays, or vectors

Written in two styles:

Block style
```
- first
- second
- third
```
Flow style
```
[first, second, third]
```

Mappings

Also called dictionary, key-value pairs, hashes, or objects
Unique keys, any valid data as values
Keys and values are separated by :

key1: value1

blocklist:
  - first
  - second

flowlist: [1.2, 2, "fifty", true]

Summary

YAML is a data formatting language
Useful in writing CI/CD configurations
Indentation is very important
- Tabs are not allowed
Mappings, sequences, and scalars are building blocks of YAML

A hierarchical graph of YAML data structure.

Editor Exercises Layout

Annotated picture of editor exercise layout displaying folder, file, and terminal area.

Let's practice!

CI/CD for Machine Learning