Yaak Day.js Plugin

A Yaak plugin that provides Day.js date/time manipulation functions as template functions for API testing and development.

Features

This plugin extends Yaak with powerful date/time manipulation capabilities using Day.js, a lightweight alternative to Moment.js.

Template Functions

dayjs

Converts dates to ISO format or UTC JSON format.

Parameters:

• dateTime (optional): Base date/time string. Leave empty for current date/time
• toUTCTime (optional): Convert to UTC format

Examples:

• {{dayjs()}} - Current date/time in local format
• {{dayjs("2024-01-15")}} - Specific date in local format
• {{dayjs("2024-01-15", true)}} - Specific date in UTC format

dayjs.format

Formats dates using custom format strings.

Parameters:

• dateTime: Base date/time string
• format: Format pattern (optional, defaults to “YYYY-MM-DD HH:mm:ss”)

Examples:

• {{dayjs.format("2024-01-15T12:00:00", "MMM DD, YYYY")}} - “Jan 15, 2024”
• {{dayjs.format("2024-01-15T12:00:00", "dddd, MMMM Do YYYY")}} - “Monday, January 15th 2024”

dayjs.from

Shows relative time from one date to another.

Parameters:

• dateTime: Target date/time
• fromDate: Reference date/time

Examples:

• {{dayjs.from("2024-01-15", "2024-01-10")}} - “5 days ago”
• {{dayjs.from("2024-02-01", "2024-01-01")}} - “in a month”

dayjs.toISOString

Converts dates to ISO 8601 string format.

Parameters:

• dateTime: Date/time string to convert

Examples:

• {{dayjs.toISOString("2024-01-15T12:00:00")}} - “2024-01-15T12:00:00.000Z”

Installation

1. Download the plugin from the releases page
2. Open Yaak and go to Settings → Plugins
3. Install the plugin by selecting the downloaded file

Usage

In Request URLs, Headers, and Bodies

Use the template functions anywhere in your HTTP requests:

POST {{baseUrl}}/api/events
Content-Type: application/json
Authorization: Bearer {{authToken}}

{
  "created_at": "{{dayjs()}}",
  "formatted_date": "{{dayjs.format("2024-01-15", "MMM DD, YYYY")}}",
  "relative_time": "{{dayjs.from("2024-01-15", "2024-01-10")}}"
}

Date Validation

The plugin automatically validates input dates. If an invalid date is provided, it will:

• Display an “Invalid Date” error message in Yaak
• Still attempt to process the request (for backward compatibility)

Supported Day.js Features

This plugin includes the following Day.js plugins:

• UTC: Time zone manipulation
• Relative Time: Human-readable time differences
• Advanced Format: Extended formatting options
• Duration: Time duration calculations
• Localized Format: Locale-aware formatting

Common Format Patterns

Pattern	Example Output	Description
YYYY-MM-DD	2024-01-15	ISO date
HH:mm:ss	14:30:45	24-hour time
MMM DD, YYYY	Jan 15, 2024	Short date
dddd, MMMM Do YYYY	Monday, January 15th 2024	Full date
YYYY-MM-DDTHH:mm:ss.SSSZ	2024-01-15T14:30:45.123Z	ISO datetime

Development

Prerequisites

• Node.js >= 18
• pnpm

Setup

git clone https://github.com/aleksanderwalczuk/yaak-dayjs-plugin.git
cd yaak-dayjs-plugin
pnpm install

Build

pnpm build

Test

pnpm test

Lint

pnpm lint
pnpm lint:fix

Contributing

1. Fork the repository
2. Create a feature branch
3. Make your changes
4. Add tests for new functionality
5. Run the test suite: pnpm test
6. Submit a pull request

License

UNLICENSED

Author

Aleksander Walczuk - ohleg@windowslive.com

Links

• GitHub Repository
• Issues
• Yaak
• Day.js Documentation