Difference Between PUT and PATCH Request

These HTTP methods handle resource manipulation differently, and many developers find it challenging to pick the right one for their needs.

Let's get into what makes PUT and PATCH requests tick in REST APIs. You'll understand the basic differences between these HTTP methods and learn when to use each one. This piece covers everything from full resource updates to partial changes, along with practical tips to implement PUT and PATCH operations the right way.

Understanding HTTP Methods

HTTP methods, also known as HTTP verbs, are the foundations of communication in REST APIs. These methods tell the server what action to perform on its resources, which creates a standardized way for clients and servers to interact.

Core Characteristics and Purpose

Developers use HTTP methods to perform CRUD (Create, Retrieve, Update, Delete) operations while you retain control between client and server. This standardized approach to resource management ensures different systems work together seamlessly.

The protocol defines several standard methods, each with its own purpose: REST APIs. These methods tell the server what action to perform on its resources, which creates a standardized way for clients and servers to interact.

Core Characteristics and Purpose

Developers use HTTP methods to perform CRUD (Create, Retrieve, Update, Delete) operations while you retain control between client and server. This standardized approach to resource management ensures different systems work together seamlessly.

The protocol defines several standard methods, each with its own purpose:

- GET : Retrieves resource information without modification

- POST : Creates new resources on the server

- PUT : Updates existing resources completely

- PATCH : Performs partial resource updates

- DELETE : Removes resources from the server

HTTP methods behavioral properties are vital aspects to understand. The methods fall into two categories: safe or unsafe, and idempotent or non-idempotent. Safe methods like GET work as read-only operations that don't change server resources. Idempotent methods, including GET, PUT, and DELETE, give you the same result no matter how many times you run them.

These standardized methods help REST APIs work by enabling predictable behavior and clear resource management. Chrome, Firefox, Safari and other modern browsers now support all standard HTTP methods. This marks a significant development from earlier days when browsers could only support GET and POST methods widely.

PUT Request: Full Resource Update

PUT requests serve as a core method in REST APIs that lets you completely replace resources. Clients must include the full resource representation in their PUT request to replace the existing resource at the specified URI.

Key Characteristics of PUT Requests:

1. The request body needs complete resource representation

2. New resources get created if the specified URI has none

3. The new representation completely replaces existing resources

4. Multiple similar requests produce the same result due to idempotency

PUT operations strictly follow replacement rules that affect all mutable attributes during updates. Clients should note that any existing attributes missing from the request body will reset to default values or get removed. This unique behavior sets PUT apart from other HTTP methods and makes it the perfect choice to handle complete resource updates.

Servers indicate successful PUT requests through status codes: 200 (OK) or 204 (No Content) for modifications, and 201 (Created) for new resources. This straightforward response system helps applications track request outcomes and manage their state effectively.

PATCH Request: Partial Resource Update

PATCH requests serve as a specialized HTTP method that modifies existing resources partially. Clients can send specific changes instead of replacing entire resources.

Key Characteristics of PATCH:

1. Makes targeted changes to existing resources

2. The system processes modifications through instruction sets

3. Changes happen atomically - success requires all changes or none apply

4. A single request can handle multiple update operations

JSON Merge Patch and JSON Patch stand as common approaches to describe changes in the PATCH method. Servers must process these modifications based on the specified content type. The header ''Content-Type: application/json-patch+json'' typically defines this specification.

The nature of PATCH operations determines their idempotency. A PATCH request becomes idempotent when updating a specific field to a new value. Non-idempotent operations include incrementing counters or adding items to arrays.

The server responds with a 204 (No Content) code after successful PATCH operations . This response confirms the applied changes. The server must confirm the PATCH document's suitability and ensure all changes align with the resource's current state.

Comparing PUT and PATCH

PUT and PATCH both update resources, but they work in very different ways. The main difference shows in how servers handle these requests. PUT replaces entire resources, and PATCH makes specific changes to existing resources.

Key Operational Differences:

1. PUT needs a complete resource representation and uses more bandwidth, while PATCH saves bandwidth by sending only the changed fields

2. PUT will always give the same results because it's idempotent, but PATCH can work either way depending on how you implement it

3. PUT sets any missing fields to null, but PATCH keeps unspecified fields unchanged

PATCH has a big advantage - clients don't need to know everything about a resource before they update it. This makes PATCH the quickest way to handle large-scale objects and helps track update changes better.

These differences make each method useful in different situations. PATCH gives you more control over updates, while PUT maintains complete resource consistency. Your choice between them depends on your application's needs and how you manage resources.

Conclusion

PUT and PATCH requests play different yet complementary roles in REST API design. PUT requests excel at keeping resources consistent through complete replacements and deliver predictable results due to their idempotent nature. PATCH requests enable quick, targeted updates that use less bandwidth and allow more flexibility for partial changes.

Each method brings unique value to specific scenarios - PUT handles full resource updates while PATCH takes care of granular modifications.

Teams should think over their application's needs when selecting between PUT and PATCH implementations.

The choice substantially depends on resource size, update frequency, and data consistency requirements. PUT requests work best when you need complete control over resources. PATCH operations prove more effective for large resources or frequent changes. This knowledge helps teams build better APIs that follow REST principles and manage resources effectively.