Start Coding

Subjects

JAVASCRIPTHTMLCSSPYTHONSQLJAVACPPCSHARPPHPTYPESCRIPTCRUBYGOSWIFTKOTLINRUSTRBASHSCALAOBJECTIVE-CDARTPERLLUAMATLABXMLJSONMARKDOWNASSEMBLYLATEXYAMLSOLIDITYBLOCKCHAIN

Topics

Introduction to YAML

What is YAMLYAML vs. JSON and XMLYAML Use CasesYAML File Extension

YAML Syntax Basics

YAML IndentationYAML CommentsYAML Key-Value PairsYAML StringsYAML NumbersYAML BooleansYAML Null Values

YAML Data Structures

YAML ListsYAML Nested ListsYAML DictionariesYAML Nested DictionariesYAML Complex Structures

YAML Advanced Features

YAML AnchorsYAML AliasesYAML Merge KeysYAML Block ScalarsYAML Folded ScalarsYAML Literal ScalarsYAML Multi-line Strings

YAML Data Types

YAML TimestampsYAML Binary DataYAML SetsYAML PairsYAML Omap

YAML Document Structure

YAML Multiple DocumentsYAML Document SeparatorsYAML DirectivesYAML Tags

YAML Best Practices

YAML Naming ConventionsYAML Formatting GuidelinesYAML Error HandlingYAML Version Compatibility

Working with YAML

YAML ParsingYAML GenerationYAML ValidationYAML in PythonYAML in RubyYAML in JavaScript

YAML in Configuration

YAML for App ConfigYAML in DockerYAML in KubernetesYAML in Ansible

YAML Security

YAML InjectionYAML Safe LoadingYAML Encryption

YAML Tools and Editors

YAML Online ValidatorsYAML IDE PluginsYAML Command-line Tools

YAML Block Scalars: Handling Multi-line Strings

YAML block scalars are essential features for managing multi-line strings in YAML configurations. They provide a clean and readable way to represent large text blocks, preserving or folding newlines as needed.

Types of Block Scalars

YAML offers two types of block scalars:

  • Literal Block Scalar (|): Preserves all newlines within the block.
  • Folded Block Scalar (>): Folds newlines to spaces, except for empty lines and more-indented lines.

Literal Block Scalar

Literal block scalars are denoted by the pipe character (|). They maintain all line breaks in the text.


description: |
  This is a multi-line
  description that preserves
  line breaks.
  Each line will appear as-is.

Folded Block Scalar

Folded block scalars use the greater-than symbol (>). They convert single line breaks to spaces, creating a single long line.


about: >
  This is a long description
  that will be folded into a
  single line. Empty lines

  create paragraph breaks.

Indentation and Chomping Indicators

Block scalars can be further customized with indentation and chomping indicators:

  • Indentation: Specify the indentation level with a number after the block scalar indicator.
  • Chomping: Control trailing newlines with '-' (strip), '+' (keep), or nothing (clip).

example: |2-
  This block is indented by 2 spaces
  and will strip all trailing newlines.

Use Cases

Block scalars are particularly useful for:

  • Configuration files with multi-line values
  • Embedding scripts or code snippets
  • Preserving formatting in text blocks

They're often used in application configurations, Docker files, and Kubernetes manifests.

Best Practices

  • Choose the appropriate scalar type based on your newline requirements.
  • Be consistent with indentation within your YAML files.
  • Use chomping indicators to control trailing newlines effectively.
  • Consider readability when deciding between block scalars and other multi-line string formats.

Related Concepts

To further enhance your YAML skills, explore these related topics:

Understanding block scalars is crucial for effectively managing complex string data in YAML. They provide a powerful tool for maintaining readability and precision in your configurations.