Why DELETE for removing resources in Rest API? - Purpose & Use Cases

The Big Idea

What if you could erase data with a single command instead of hunting through files?

The Scenario

Imagine you have a huge list of contacts stored in a file. To remove one contact, you open the file, find the contact, delete the line manually, and save it again. This is slow and tricky, especially if many people need to remove contacts at the same time.

The Problem

Manually editing files or databases to remove items is error-prone. You might delete the wrong contact or forget to save changes. It also takes a lot of time and effort, especially when many users want to remove different contacts simultaneously.

The Solution

The DELETE method in REST APIs lets you tell the server exactly which resource to remove with a simple request. This makes removing data fast, safe, and easy to automate without opening files or risking mistakes.

Before vs After

✗ Before

open file
find contact
remove line
save file

✓ After

DELETE /contacts/{contact_id}

What It Enables

DELETE lets you quickly and reliably remove specific resources from a server with a simple, standard command.

Real Life Example

When you delete a photo from your online album, the app sends a DELETE request to remove that photo from the server instantly, without you needing to manage files yourself.

Key Takeaways

Manual removal is slow and risky.

DELETE method automates safe resource removal.

It simplifies managing data on servers.

Practice

1. What is the main purpose of the HTTP DELETE method in REST APIs?

easy

A. To remove a resource identified by a URL

B. To create a new resource on the server

C. To update an existing resource

D. To retrieve data from the server

Solution

1. Step 1: Understand HTTP methods

   HTTP methods define actions on resources. DELETE is specifically for removal.

2. Step 2: Identify DELETE's role

   DELETE removes the resource at the given URL, unlike POST (create), PUT/PATCH (update), or GET (retrieve).

3. Final Answer:

   To remove a resource identified by a URL -> Option A

4. Quick Check:

   DELETE = remove resource [OK]

Hint: DELETE always removes resource at the URL, no body needed [OK]

Common Mistakes:

• Confusing DELETE with GET or POST
• Thinking DELETE requires a request body
• Assuming DELETE creates or updates data

2. Which of the following is the correct syntax to send a DELETE request to remove a user with ID 123 using curl?

easy

A. curl -X GET https://api.example.com/users/123

B. curl -X PUT https://api.example.com/users/123

C. curl -X POST https://api.example.com/users/123

D. curl -X DELETE https://api.example.com/users/123

Solution

1. Step 1: Identify HTTP method for deletion

   DELETE method is used to remove resources, so -X DELETE is correct.

2. Step 2: Check URL and method usage

   The URL targets user 123, and curl uses -X to specify method. So, curl -X DELETE URL is correct.

3. Final Answer:

   curl -X DELETE https://api.example.com/users/123 -> Option D

4. Quick Check:

   curl DELETE syntax = curl -X DELETE URL [OK]

Hint: Use curl -X DELETE followed by resource URL [OK]

Common Mistakes:

• Using GET or POST instead of DELETE
• Omitting the -X flag for method
• Using PUT which is for updates

3. Given this Python code using requests library:

import requests
response = requests.delete('https://api.example.com/items/45')
print(response.status_code)

What will be printed if the item was successfully deleted?

medium

A. 201

B. 404

C. 200

D. 500

Solution

1. Step 1: Understand HTTP status codes for DELETE

   Successful DELETE usually returns 200 (OK) or 204 (No Content). 200 means success with response body.

2. Step 2: Check options for success code

   Among options, 200 indicates success. 404 means not found, 500 server error, 201 created (not for DELETE).

3. Final Answer:

   200 -> Option C

4. Quick Check:

   DELETE success = 200 OK [OK]

Hint: Successful DELETE usually returns 200 or 204 status code [OK]

Common Mistakes:

• Confusing 201 (created) with success for DELETE
• Assuming 404 means success
• Ignoring status code meanings

4. Consider this JavaScript fetch code to delete a post:

fetch('https://api.example.com/posts/10', {
  method: 'DELETE',
  body: JSON.stringify({ id: 10 })
})
.then(res => res.status)
.then(console.log)

What is the main issue with this code?

medium

A. The URL is incorrect

B. DELETE requests should not have a body

C. The method should be GET

D. Missing headers for JSON content

Solution

1. Step 1: Understand DELETE request body rules

   DELETE usually does not require a request body; many servers ignore or reject it.

2. Step 2: Identify the problem in code

   The code sends a JSON body with DELETE, which is often unnecessary and may cause errors.

3. Final Answer:

   DELETE requests should not have a body -> Option B

4. Quick Check:

   DELETE usually no body [OK]

Hint: Avoid sending body with DELETE requests [OK]

Common Mistakes:

• Adding unnecessary body to DELETE
• Confusing method with GET or POST
• Forgetting to check server docs for DELETE body support

5. You want to delete multiple resources in one request using REST API. Which approach is best practice?

hard

A. Send multiple DELETE requests, one per resource URL

B. Send a single DELETE request with a JSON array body listing IDs

C. Use POST method with action=delete and list of IDs in body

D. Use GET method with query parameters to delete resources

Solution

1. Step 1: Understand REST principles for DELETE

   DELETE targets a single resource URL. Bulk delete is not standardized and often unsupported.

2. Step 2: Evaluate options for bulk deletion

   Sending multiple DELETE requests (one per resource) is standard and reliable. Other methods misuse HTTP verbs or semantics.

3. Final Answer:

   Send multiple DELETE requests, one per resource URL -> Option A

4. Quick Check:

   One DELETE per resource URL [OK]

Hint: Delete resources one by one with separate DELETE requests [OK]

Common Mistakes:

• Trying to send bulk delete in one DELETE with body
• Using POST or GET to delete resources
• Assuming server supports bulk delete by default