JavaScript API Response - conditional statement for handling a 'null' response

Question

JavaScript API Response - conditional statement for handling a 'null' response

Does anyone have any suggestions for the following scenario:

I have a response in .json format containing personal data of a person, who may or may not be assigned to a project.

Here is an example response where the person is not assigned to a project:

"contactPerson": {
      "id": "someUUID",
      "firstName": "string",
      "lastName": "string",
      "email": "string",
      "title": "string"
    },
    "project": null

And here is an example response where the person is assigned to a project:

"contactPerson": {
      "id": "someUUID",
      "firstName": "string",
      "lastName": "string",
      "email": "string",
      "title": "string"
    },
    "project": {
      "id": "projectUUID",
      "name": "This is a project name ",
      "fullName": "This is a full project name with over 55 chars",
}

I've tried using a simple if statement, but it hasn't been successful.

if (typeOf(response.body[i].project.id !== null) {
 //assert elements in project array
} else {
//assert is 'null
}

However, I keep getting the following error:

Cannot read properties of null (reading 'id')

Does anyone have a solution on how to resolve this issue? I need to assert whether a project is assigned or not.

Thank you in advance

javascript api rest cypress

Answer 1

Answer №1

It's important to note that response.body[i].project.id will not have a defined value because response.body[i].project is actually null.

This situation will result in an error being thrown;

TypeError: Cannot read properties of null (reading 'id')

As noted in the comments, simply verifying the existence of response.body[i].project is sufficient.

Using typeof on response.body[i].project will indicate that it is indeed an object.

In order to handle this scenario effectively, you can:

if(response.body[i].project)

This approach works because null is considered a falsy value, so it is equivalent to:

if(response.body[i].project == null)

To explicitly check for null:

if(Object.is(response.body[i].project, null))

Or

if(response.body[i].project === null)

const response = {
  "contactPerson": {
      "id": "someUUID",
      "firstName": "string",
      "lastName": "string",
      "email": "string",
      "title": "string"
    },
    "project": null
};

console.log(response.project); // null

console.log(typeof(response.project)); // object

console.log(response.project == null); // true

console.log(response.project === null); // true

console.log(Object.is(response.project, null)); // true

Answer 2

It's important to note that response.body[i].project.id will not have a defined value because response.body[i].project is actually null.

This situation will result in an error being thrown;

TypeError: Cannot read properties of null (reading 'id')

As noted in the comments, simply verifying the existence of response.body[i].project is sufficient.

Using typeof on response.body[i].project will indicate that it is indeed an object.

In order to handle this scenario effectively, you can:

if(response.body[i].project)

This approach works because null is considered a falsy value, so it is equivalent to:

if(response.body[i].project == null)

To explicitly check for null:

if(Object.is(response.body[i].project, null))

Or

if(response.body[i].project === null)

const response = {
  "contactPerson": {
      "id": "someUUID",
      "firstName": "string",
      "lastName": "string",
      "email": "string",
      "title": "string"
    },
    "project": null
};

console.log(response.project); // null

console.log(typeof(response.project)); // object

console.log(response.project == null); // true

console.log(response.project === null); // true

console.log(Object.is(response.project, null)); // true

JavaScript API Response - conditional statement for handling a 'null' response

Answer №1

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