@alpnpmrepo/multiline-key-value-parser

A generic parser for multi-line key-value formats including Java properties files, environment files, and similar config formats. Preserves formatting, comments, and blank lines.

Installation

npm install @alpnpmrepo/multiline-key-value-parser

Usage

import { MultiLineKeyValueParser } from '@alpnpmrepo/multiline-key-value-parser';

// Parse properties
const content = `
# Database configuration
db.host=localhost
db.port=5432
db.name=myapp
`;

const parsed = MultiLineKeyValueParser.parseProperties(content);
// Result: { 'db.host': 'localhost', 'db.port': '5432', 'db.name': 'myapp' }

// Update values while preserving formatting
const updated = { 'db.host': 'prod-server', 'db.port': '5432', 'db.name': 'myapp' };
const serialized = MultiLineKeyValueParser.serializeProperties(updated, content);
// Original comments, blank lines, and indentation are preserved

Features

• Multiple formats: Supports both key=value and key: value syntax
• Multi-line values: Handles backslash continuations (\)
• Comment preservation: Maintains # comments during serialization
• Blank line handling: Preserves formatting structure
• Type-safe: Built with TypeScript strict mode
• Zero dependencies: Pure TypeScript implementation

API

parseProperties(content: string): Record<string, string>

Parses key-value content into an object.

serializeProperties(obj: Record<string, string>, originalContent: string): string

Serializes object back to formatted string, preserving original structure.

extractPropertyValue(content: string, key: string): string | undefined

Extracts a single property value from content.

extractPropertyKeys(content: string): string[]

Returns all property keys found in content.

License

MIT

Author

[email protected]