Yaak DateAdd Plugin

A Yaak template function plugin that allows you to add or subtract time from the current date/time and format the output.

⚠️ IMPORTANT - ALL FIELDS ARE REQUIRED

Due to Yaak plugin API limitations, ALL 7 fields must be filled in:

1. Years - Enter 0 if you don’t want to add/subtract years
2. Months - Enter 0 if you don’t want to add/subtract months
3. Days - Enter 0 if you don’t want to add/subtract days
4. Hours - Enter 0 if you don’t want to add/subtract hours
5. Minutes - Enter 0 if you don’t want to add/subtract minutes
6. Seconds - Enter 0 if you don’t want to add/subtract seconds
7. Format - Enter a format string like YYYY-MM-DD HH:mm:ss

You cannot leave fields blank - Yaak will show “Missing required argument” errors. You must type something in each field (use 0 for time adjustments you don’t need).

Additional Notes

🕒 Always uses current date/time - The plugin always starts from the current date/time. A base date/time parameter is not currently supported due to Yaak plugin API limitations.

Features

• Add or subtract years, months, days, hours, minutes, and seconds from the current date/time
• Support for negative values to subtract time periods
• Flexible date formatting with common format tokens
• Simple and intuitive interface
• Note: Base date/time parameter not currently available due to Yaak API limitations

Installation

Option 1: Manual Installation (Development)

1. Install the Yaak CLI:

npm install -g @yaakapp/cli

2. Clone or create the plugin directory:

mkdir yaak-plugin-dateadd
cd yaak-plugin-dateadd

3. Copy the plugin files (package.json, tsconfig.json, and src/index.ts) to this directory

4. Install dependencies:

npm install

5. Build the plugin:

npm run build

6. Install the plugin in Yaak:
   • Open Yaak
   • Go to Settings > Plugins
   • Click “Install from folder”
   • Select the plugin directory

Option 2: Development Mode

For active development, use the dev command to watch for changes:

npm run dev

Usage

Once installed, you can use the dateAdd template function in your Yaak requests.

⚠️ CRITICAL: How to Use the Plugin

1. Insert ${[ dateAdd() ]} in your request
2. Click the blue template tag to open the form
3. YOU MUST ENTER A VALUE IN EVERY FIELD - cannot leave any blank
4. For time units you don’t need, type 0
5. For the format field, type a format string like YYYY-MM-DD HH:mm:ss

Basic Examples

Current date/time with standard format:

${[ dateAdd('0', '0', '0', '0', '0', '0', 'YYYY-MM-DD HH:mm:ss') ]}

Result: 2025-03-20 14:30:45

7 days from now:

${[ dateAdd('0', '0', '7', '0', '0', '0', 'YYYY-MM-DD') ]}

Result: 2025-03-27

3 hours and 30 minutes from now:

${[ dateAdd('0', '0', '0', '3', '30', '0', 'YYYY-MM-DD HH:mm:ss') ]}

Result: 2025-03-20 18:00:45

1 year, 2 months, 15 days from now:

${[ dateAdd('1', '2', '15', '0', '0', '0', 'YYYY-MM-DD') ]}

Result: 2026-06-04

Go back 7 days (negative values work):

${[ dateAdd('0', '0', '-7', '0', '0', '0', 'YYYY-MM-DD') ]}

Result: 2025-03-13

Complex calculation:

${[ dateAdd('1', '2', '15', '3', '30', '45', 'YYYY-MM-DD HH:mm:ss') ]}

Adds 1 year, 2 months, 15 days, 3 hours, 30 minutes, and 45 seconds from now.

Format Tokens

The plugin supports the following format tokens:

Token	Description	Example
YYYY	4-digit year	2025
YY	2-digit year	25
MMMM	Full month name	January
MMM	Short month name	Jan
MM	2-digit month	01
M	Month number	1
DD	2-digit day	05
D	Day number	5
dddd	Full day name	Monday
ddd	Short day name	Mon
dd	Min day name	Mo
d	Day of week (0-6)	1
HH	24-hour (2-digit)	13
H	24-hour	13
hh	12-hour (2-digit)	01
h	12-hour	1
mm	2-digit minutes	05
m	Minutes	5
ss	2-digit seconds	09
s	Seconds	9
SSS	Milliseconds	123
A	AM/PM uppercase	PM
a	am/pm lowercase	pm
Z	Timezone offset	+01:00
ZZ	Timezone offset (no colon)	+0100
X	Unix timestamp (seconds)	1735000000
x	Unix timestamp (milliseconds)	1735000000000

Common Format Examples

Format	Example Output
YYYY-MM-DD	2025-01-15
DD/MM/YYYY	15/01/2025
MM/DD/YYYY	01/15/2025
MMMM D, YYYY	January 15, 2025
dddd, MMMM D, YYYY	Wednesday, January 15, 2025
YYYY-MM-DD HH:mm:ss	2025-01-15 14:30:45
DD MMM YYYY HH:mm	15 Jan 2025 14:30
YYYY-MM-DDTHH:mm:ssZ	2025-01-15T14:30:45+01:00
X	1735000000 (Unix timestamp)

Use Cases

API Testing

• Generate dynamic expiration dates and times for tokens
• Create date/time ranges for queries
• Test date validation with future/past dates and times
• Generate timestamps for time-based operations

Example: Authorization Header with Expiry

{
  "Authorization": "Bearer token",
  "Expires": "${[ dateAdd('', 0, 0, 7, 0, 0, 0, 'YYYY-MM-DDTHH:mm:ssZ') ]}"
}

Example: Query Past Date Range

GET /api/reports?start_date=${[ dateAdd('', 0, 0, -30) ]}&end_date=${[ dateAdd() ]}

Example: Future Appointment Booking with Time

{
  "appointment_date": "${[ dateAdd('', 0, 0, 14, 9, 0, 0, 'YYYY-MM-DDTHH:mm:ss') ]}",
  "follow_up_date": "${[ dateAdd('', 0, 0, 44, 9, 0, 0, 'YYYY-MM-DDTHH:mm:ss') ]}"
}

Example: Token Expiry (1 hour from now)

{
  "token": "abc123",
  "expires_at": "${[ dateAdd('', 0, 0, 0, 1, 0, 0, 'X') ]}"
}

Example: Scheduled Task (30 minutes from a specific time)

{
  "scheduled_time": "${[ dateAdd('2025-10-22T14:00:00', 0, 0, 0, 0, 30, 0, 'YYYY-MM-DDTHH:mm:ssZ') ]}"
}

Development

Project Structure

yaak-plugin-dateadd/
├── src/
│   └── index.ts          # Plugin source code
├── package.json          # Package configuration
├── tsconfig.json         # TypeScript configuration
└── README.md            # This file

Building

npm run build

Development Mode

npm run dev

Comparison with Insomnia DateAdd

This plugin is inspired by the DateAdd plugin for Insomnia by SebBrookfield. It provides enhanced functionality for Yaak users:

• Same core functionality (days, months, years, format)
• Enhanced: Support for hours, minutes, and seconds
• Enhanced: Optional base date/time parameter
• Support for negative values
• Compatible format tokens (no external dependencies like moment.js)
• Smart default formatting based on which time units are used

License

MIT

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

Support

For issues or questions:

• Open an issue on GitHub
• Check the Yaak Plugin Documentation

Credits

• Inspired by SebBrookfield/DateAdd for Insomnia
• Built for Yaak API Client