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kanishkrawatt for Requestly

Posted on • Originally published at requestly.com

How Lodash Can Simplify Your API Testing

#api #apitesting #testing #lodash

API testing can get messy fast. You deal with deeply nested JSON, inconsistent response structures, repetitive validations, and way too much boilerplate. Lodash cuts through all of that. And since Requestly exposes Lodash globally as _ inside your Script Tab, you can start using its utilities instantly, no importing or setup required.This article breaks down how Lodash actually makes API testing easier, with examples you can plug straight into your Requestly scripts.

Why Lodash Is a Game-Changer for API Testing

Most API testing involves tasks like:

  • Extracting values from deeply nested response objects
  • Filtering arrays
  • Checking for missing fields
  • Comparing expected vs actual data
  • Transforming inconsistent data
  • Creating small helpers on the fly

Doing all that with plain JavaScript works… but it’s verbose, error-prone, and annoying. Lodash gives you battle-tested helpers that simplify all of these into one-liners.

Using Lodash Inside Requestly Scripts

You don’t need to install or import anything. Lodash is already available globally as _ inside Requestly’s scripting environment.

console.log(_.toUpper('requestly')); // REQUESTLY

This means you can clean, inspect, validate, and transform data right where you're testing.

Practical Use Cases for API Testing

1. Check if a Field Exists 

if (!_.has(responseBody, 'data.user.email')){ 
    console.log('❌ Missing email field'); 
}
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2. Validate That Two Responses Match 

const expected = { status: 'active', plan: 'premium' }; 
const actual = responseBody.profile; 
if (_.isEqual(expected, actual)) { 
    console.log('✔️ Profile matches expected structure'); 
}
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3. Filter Arrays Cleanly 

const activeUsers = _.filter(responseBody.users, u => u.active);
console.log('Active:', activeUsers);
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4. Map Data for Assertions or Next Requests 

const names = _.map(responseBody.users, u => u.name);
console.log('User names:', names);
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5. Safely Get Deep Values 

const role = _.get(responseBody, 'data.profile.role', 'unknown');
console.log('Role:', role);
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6. Remove Unwanted Fields Before Passing Data Forward 

const sanitized = _.omit(responseBody.user, ['password', 'token']);
console.log(sanitized);
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Why Lodash Fits Perfectly With Requestly’s Script Runner

Lodash shines in scenarios like:

  • Writing assertions in response scripts
  • Cleaning API responses before chaining requests
  • Normalizing data for comparison
  • Generating structured logs
  • Avoiding brittle manual validations

If you run multi-step workflows or collection runs in Requestly, Lodash quickly becomes your go-to toolkit.

More Tools Available in Requestly

Requestly provides many other global utilities, third party plugins, and helpful libraries that you can use instantly inside scripts.
Learn more here: Import Packages into Your Scripts

Final Thoughts

Lodash doesn’t just simplify API testing, it removes friction entirely. Shorter scripts, clearer logic, fewer bugs. And since Requestly includes Lodash globally as _, you can use it instantly without any setup.

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