Description

In web development and API interactions, HTTP request methods serve as the core mechanisms for client-server communication. The HTTP/1.1 protocol defines eight fundamental request methods, each representing distinct operations on resources. This article will systematically explain these eight HTTP methods and their application scenarios, aiming to help developers design more standardized APIs while providing technical references for users of website online monitoring products.

Analysis of HTTP Request Methods

1. GET – Data Retrieval

Purpose: Request specified resources

Characteristics:

• Parameters transmitted via URL (visible in browser history)

• Native cache support mechanism

• Idempotent and safe, ideal for data query scenarios

Example:

GET /products/123 HTTP/1.1
Host: api.example.com

Security Monitoring Focus:

Prevent sensitive data exposure in URLs

Best Practices:

• Adhere to 2048-character length limit

• Use POST for sensitive parameters

2. POST – Data Submission​​

Purpose: Create new resources or trigger processing operations

Characteristics:

• Parameters placed in the request body (supports complex data structures)

• Non-idempotent; repeated submissions may yield different outcomes

• Default encoding type: application/x-www-form-urlencoded

Example:

POST /users HTTP/1.1
Content-Type: application/json
{“name”:”John”,”email”:”john@example.com”}

Typical Scenarios:

• Form submissions

• File uploads

• Triggering batch processing tasks

Monitoring Applications: Frequently used in API call monitoring to detect abnormal submission behaviors like duplicate submissions.

3. PUT – Resource Replacement

Purpose: Full update of existing resources

Characteristics:

• Idempotent operation (identical outcomes with multiple executions)

• Requires complete resource path specification

• Automatically overwrites target resources

Example:

PUT /api/users/123 HTTP/1.1
Content-Type: application/json
{ “name”: “Alice Smith”, “email”: “john@example.com” }

4. DELETE – Resource Deletion

Purpose: Request server to remove specified resources

Key Considerations:

• Actual deletion depends on server implementation

• Idempotent nature ensures safety of repeated requests

• Recommended to use with permission verification

Monitoring Scenarios: Log audit trails of deletion operations

Best Practices: Use with authentication mechanisms

Example:

DELETE /api/users/123 HTTP/1.1
Host: example.com

5. HEAD – Metadata Retrieval​​

Purpose: Fetch resource metadata (80% less data transfer than GET)

Use Cases: Link validity checks

Example:

HEAD /api/users/123 HTTP/1.1

6. PATCH – Partial Resource Update​​

Purpose: Apply partial modifications to existing resources (more bandwidth-efficient than PUT)

Characteristics:

Updates specific fields instead of replacing entire resource

Reduces payload size for partial changes

Example:

PATCH /api/users/123 HTTP/1.1
Content-Type: application/json
{ “email”: “new.john@example.com” }

7. OPTIONS – Method Discovery

Purpose: Probe server-supported HTTP methods

Response Header Example:

Allow: GET, HEAD, OPTIONS

8. TRACE – Message Loopback Testing

Purpose: Diagnose request/response chains via echo responses

HTTP Request Methods Comparison Matrix

Method	Safe	Idempotent	Request Body	Cacheable	Form Support
GET	√	√	×	√	√
POST	×	×	√	×	√
PUT	×	√	√	×	×
DELETE	×	√	×	×	×
PATCH	×	×	√	×	×
HEAD	√	√	×	√	×

Application Scenarios of HTTP Request Methods

• User System

Create User: POST /users

Retrieve User: GET /users/{id}

Update Profile: PUT /users/{id}

Delete Account: DELETE /users/{id}

• File Management

Chunked Upload: PATCH /files/{id}

Metadata Retrieval: HEAD /files/{id}

• API Discovery

Method Support Detection: OPTIONS /api

Development Considerations

Method Selection Principles

RESTful Compliance: Select methods based on resource state transitions

Security Priority: Prioritize POST/PUT for sensitive operations

Performance Optimization: Use GET with caching for high-frequency data access

Version Control: Implement API versioning via URL or headers

Security Standards

GET Requests: Must not modify resource states

CSRF Protection: Enforce for state-changing operations

Performance Optimization

HEAD Method: Rational utilization to reduce bandwidth consumption

Retry Strategy: Implement automatic retry mechanisms for idempotent requests

Monitoring Recommendations

Track abnormal method usage frequency (alert if TRACE utilization > 0.1%)

Detect PUT/PATCH misuse (trigger warnings when error rate exceeds 5%)

Mastering HTTP method characteristics not only enhances API design quality but also enables precise anomaly detection through granular monitoring.