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/tool/ CURL CONVERTER · OPENAPI DOCS · MIME TYPES · KEYCODE INSPECTOR · 100% PRIVATE

cURL to Fetch/Axios/Python/Go · OpenAPI to Markdown Tables · 150+ MIME Types · RFC 9110 HTTP Reference · Live KeyCode Sandbox

Target Language:
Terminal cURL Command
Parsed BreakdownPOST
Target URL: https://api.example.com/v1/payments
Headers: 2 headers
Payload: 61 bytes
Generated Code (fetch)
// JavaScript (fetch API)
async function makeRequest() {
  const url = 'https://api.example.com/v1/payments';
  const options = {
    method: 'POST',
    headers: {
      'Content-Type': "application/json",
      'Authorization': "Bearer token_live_83921",
    },
    body: JSON.stringify({"amount": 4900, "currency": "usd", "customer": "cust_12345"}),
  };

  try {
    const response = await fetch(url, options);
    const data = await response.json();
    console.log('Status:', response.status);
    console.log('Data:', data);
  } catch (error) {
    console.error('Request failed:', error);
  }
}

makeRequest();

cURL Command Translation in Modern Full-Stack Development

The curl command-line utility has been the universal lingua franca of network debugging, API documentation, and server communication since its inception in 1996. Developers, third-party API providers (like Stripe, GitHub, AWS, and Twilio), and browser DevTools ("Copy as cURL") all output HTTP requests as raw terminal cURL strings.

However, manually translating a multi-line cURL command containing query parameters, Authorization Bearer tokens, JSON payloads, and custom headers into native application code is error-prone. LocalDevTools's client-side tokenizer parses flags (-X, -H, -d, -u, -b, --compressed) and compiles them instantly into clean, modern language equivalents:

  • JavaScript fetch() API: Modern ECMAScript async/await syntax compatible with browser scripts, Next.js server actions, and Cloudflare Workers.
  • JavaScript Axios: Clean configuration object syntax for enterprise React, Vue, and Node.js microservices.
  • Python 3 requests: Idiomatic Python dictionary syntax with automatic JSON payload serialization.
  • Go (net/http): Production-ready Go standard library code with http.NewRequest and response body reader cleanup.
  • PHP cURL: Standard curl_setopt_array() implementation for WordPress plugins and Laravel controllers.

Transforming OpenAPI 3.x and Swagger 2.x into GitHub-Ready Markdown

The OpenAPI Specification (OAS) is the global standard for defining RESTful APIs in YAML or JSON. While full-scale doc generators like Swagger UI or Redoc are excellent for hosted portals, engineers frequently need quick, portable documentation tables directly inside GitHub README.md files, internal Notion wikis, or engineering design documents.

LocalDevTools parses raw OpenAPI 3.0, 3.1, and Swagger 2.0 definitions directly inside your browser using client-side YAML parsing. It extracts endpoint paths, HTTP verbs, parameter types, required fields, and response schemas, outputting formatted Markdown tables with zero build steps or server uploads required.

IANA MIME Types & HTTP Content-Type Header Architecture

MIME (Multipurpose Internet Mail Extensions) types, formally standardized by the Internet Assigned Numbers Authority (IANA), instruct web browsers and HTTP clients on how to interpret byte streams received over the network. Setting an incorrect Content-Type header causes browser rendering bugs, such as SVG images downloading as plain text or WebAssembly binaries failing to instantiate.

LocalDevTools's searchable MIME reference covers over 150 standardized file formats, categorizing them by media class (Application, Text, Image, Audio, Video, Font) and distinguishing between text UTF-8 streams and binary byte payloads.

RFC 9110 HTTP Status Code Classification & Semantics

HTTP response status codes summarize the outcome of an HTTP transaction as defined in RFC 9110 (which obsoleted RFC 7231 and RFC 2616). They are grouped into five distinct semantic classes:

1xx (Informational)

Request received, continuing process (e.g. 100 Continue, 101 Switching Protocols for WebSockets, 103 Early Hints).

2xx (Successful)

Action successfully received, understood, and accepted (200 OK, 201 Created for POST, 204 No Content for DELETE).

3xx (Redirection)

Further action must be taken to complete request (301 Permanent SEO Redirect, 304 Not Modified cache validation, 307 Temporary).

4xx (Client Error)

Request contains bad syntax or cannot be fulfilled (400 Bad Request, 401 Unauthorized, 403 Forbidden, 404 Not Found, 429 Rate Limited).

Modern DOM Keyboard Event Standards: Why event.code Replaces keyCode

For decades, web developers relied on numerical event.keyCode and event.which attributes (e.g. 13 for Enter, 27 for Escape, 37 for ArrowLeft). However, the W3C officially deprecated both attributes because their numerical values vary wildly across international keyboard layouts (QWERTY vs AZERTY vs Dvorak), operating systems, and browser engines.

Modern web standards dictate using:

  • event.key: Represents the printed character or semantic action produced by the key (e.g. 'a', 'A', 'Enter', 'Backspace'). This value is layout-aware.
  • event.code: Identifies the physical key on the keyboard hardware (e.g. 'KeyA', 'Digit1', 'Space'). This value never changes regardless of keyboard language layout or shift state, making it ideal for games and shortcuts.

Frequently Asked Questions (FAQ)

Are my private API tokens, passwords, or cURL commands sent to any server? ↓

Never. LocalDevTools is built on strict zero-server client execution. All cURL tokenization, code synthesis, OpenAPI YAML parsing, and keyboard event detection happen 100% inside your local web browser's JavaScript runtime. No requests, secrets, or payloads are ever logged, transmitted, or stored on external servers.

How do I copy a cURL command from Chrome or Firefox DevTools? ↓

Open your browser's Developer Tools (F12 or Ctrl+Shift+I), click on the Network tab, and trigger any HTTP request. Right-click on the desired request in the table, hover over Copy, and select Copy as cURL (or Copy as cURL (bash)). Paste that command into LocalDevTools to convert it to Fetch, Axios, Python, or Go.

What is the difference between HTTP 301 and HTTP 308 redirects? ↓

Both status codes indicate permanent URL redirects. However, under historical implementations of HTTP 301, browsers frequently converted a POST request into a GET request when following the redirect. HTTP 308 was introduced in RFC 7538 to strictly mandate that the HTTP client must NOT change the request method (a POST to a 308 redirect must follow up with a POST to the new location).

Why is keyCode deprecated in JavaScript, and what should I use instead? ↓

event.keyCode was deprecated because numerical codes varied across browsers, operating systems, and foreign language keyboards. Modern web applications should use event.key for character input (e.g. checking if the user typed 'Enter' or 'Escape') or event.code for physical hardware key detection (e.g. checking 'KeyW' or 'ArrowUp' for game movement regardless of layout).

Can I convert Swagger 2.0 specifications as well as OpenAPI 3.0? ↓

Yes. LocalDevTools supports both legacy Swagger 2.0 (with host, basePath, and schemes) and modern OpenAPI 3.0.x / 3.1.x specifications in either YAML or JSON format, compiling them into formatted Markdown tables.