minimal-api-file-upload

Implement secure file upload endpoints in ASP.NET Core minimal APIs.

42|10|Updated Mar 27, 2026

Search Tags:#security #streaming #file upload #ASP.NET Core #ASP.NET #minimal APIs

Ready to run

npx skills add https://github.com/managedcode/PrompterOne --skill minimal-api-file-upload-managedcode

💬 Prompt for ChatGPT / Claude Chat▼

Please help me install this Agent Skill.
Skill: minimal-api-file-upload
Source: https://github.com/managedcode/PrompterOne/tree/main/.codex/skills/minimal-api-file-upload
Command: npx skills add https://github.com/managedcode/PrompterOne --skill minimal-api-file-upload-managedcode

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill requires Microsoft.AspNetCore, and includes scripts (resource) and references (resource) components.

What problem does it solve?

This Skill streamlines the process of implementing file upload endpoints in ASP.NET Core minimal APIs (.NET 8+), reducing integration complexity.

Core Features & Use Cases

Endpoint Setup: Provides guidance for creating endpoints to handle single and multiple file uploads with size and type validation.
Size Limits Configuration: Explains how to set request and multipart body size limits at Kestrel and endpoint level.
Security Measures: Emphasizes file content validation through magic bytes and safe filename generation to prevent vulnerabilities.
Streaming Support: Demonstrates how to stream large files directly to storage using MultipartReader, avoiding buffering issues.
Use Case: Imagine building an API that accepts large user uploads or media files while maintaining performance and security.

Quick Start

Use the minimal-api-file-upload skill to implement a secure file upload endpoint in your ASP.NET Core project.

Frequently Asked Questions about minimal-api-file-upload

High-intent search queries and answers about installing and using this skill.

FAQPage Schema

How do I handle large file uploads in ASP.NET Core minimal APIs?▼

Handle large file uploads in ASP.NET Core minimal APIs by using MultipartReader to stream files directly to storage. This approach avoids memory buffering issues while maintaining high performance during the transfer.

What is the best way to validate file content in ASP.NET Core minimal APIs?▼

The best way to validate file content in ASP.NET Core minimal APIs is by checking magic bytes and generating safe filenames. These security measures prevent vulnerabilities associated with malicious uploads.

How do I configure size limits for file uploads in ASP.NET Core minimal APIs?▼

Configure file upload size limits in ASP.NET Core at both the Kestrel server level and the individual endpoint level. This ensures multipart body requests adhere to strict boundary requirements.

Does ASP.NET Core minimal APIs support streaming multiple file uploads?▼

Yes, ASP.NET Core minimal APIs support streaming multiple file uploads. You can create endpoints to handle multiple files simultaneously with size and type validation while streaming directly.

Why do file uploads fail for large requests in ASP.NET Core minimal APIs?▼

File uploads fail for large requests in ASP.NET Core when Kestrel multipart body size limits are exceeded. You must configure request size limits at the server and endpoint levels to resolve this.