How to Build a Weather App in VSCode for Beginners(2): Post-response Automated Testing

Make sure you have the EchoAPI for VS Code extension installed in VSCode. Once installed, you'll be able to test and automate requests within the EchoAPI interface. It is Free to use!!!

Create a GET request:

Set the method to GET.

Use the following URL for testing the weather API:

http://localhost:3000/weather?city=London

Click 'Send' to make sure your request works and returns the correct weather data. You should see a JSON response in Response like this:

Go to the Post-response tab in EchoAPI for your request.

Add a Post-response script using JavaScript to automatically check the weather data.

Here’s an example of a simple post-scripts script that verifies:

• The response status is 200 (OK).


• The response contains a Temperature field and ensure the 'temperature' is a number


• The response contains a Weather field and ensure the 'weather' field is a string


• The response contains a City field and ensure the 'city' field is a string
  

// Check if the response status is 200 (OK)



pm.test("Status code is 200", function () {

  pm.response.to.have.status(200);

});



// Check if the response has 'temperature', 'weather', and 'city' fields



pm.test("Response contains temperature, weather, and city", function () {

  var jsonData = pm.response.json();

  pm.expect(jsonData).to.have.property('temperature');

  pm.expect(jsonData).to.have.property('weather');

  pm.expect(jsonData).to.have.property('city');

});



// Ensure the 'temperature' is a number



pm.test("Temperature is a number", function () {

  var jsonData = pm.response.json();

  pm.expect(jsonData.temperature).to.be.a('number');

});



// Ensure the 'weather' field is a string



pm.test("Weather is a string", function () {

  var jsonData = pm.response.json();

  pm.expect(jsonData.weather).to.be.a('string');

});



// Ensure the 'city' field is a string



pm.test("City is a string", function () {

  var jsonData = pm.response.json();

  pm.expect(jsonData.city).to.be.a('string');

});

Run the Test

After adding the test script, hit 'Send' again' to run your request and automatically execute the test script.

Then click 'Test result' on the right side.

Automate Post-response with More Tasks (Optional)

If you want to do multiple Post-response Automated Testings, you can add additional tasks in the Post-response section. This allows you to run all your tests at once in a single go.

We can add different requests for multiple cities, error scenarios and attach specific test scripts to each one in our case.

// Check if the response status is 500 (Internal Server Error) for invalid cities



pm.test("Status code is 500 for invalid city", function () {

  pm.response.to.have.status(500);

});



// Check for the error message in the response



pm.test("Error message is returned for invalid city", function () {

  var jsonData = pm.response.json();

  pm.expect(jsonData).to.have.property('error');

  pm.expect(jsonData.error).to.eql("Failed to fetch weather data");

});

When you run this test, EchoAPI will automatically verify that your API responds with the correct error message and status code for invalid input.

Change the request URL to New York:

http://localhost:3000/weather?city=New%20York

Here’s the script you’ll add in the Post-response section:

// Ensure the 'City' is New York"

pm.test("City is 🍎", function () {

  var jsonData = pm.response.json();

  pm.expect(jsonData.city).to.eql("New York");

});

Once you’ve added this script, click 'Send' again. EchoAPI will automatically run all the tests and show you which tests passed and which ones failed.

Here is the result:

Turn on and off the post-response execution by toggling the switch.