cURL → Rust (reqwest & tokio)
Transform cURL commands into idiomatic, asynchronous Rust HTTP requests using reqwest, serde_json, custom headers, and tokio runtime.

cURL to Rust (reqwest & tokio) Code Generator

Transform cURL commands into idiomatic, asynchronous Rust HTTP requests using reqwest, serde_json, custom headers, and tokio runtime.

100% Client-Side Privacy
Zero Server Transmission
Presets:
Format serde_json Payloads
Parse Response Body (Text / JSON)
Robust Error Handling (Result & ?)
Use rustls-tls (Pure Rust TLS)
cURL Command Input
//! cURL to Rust HTTP Client generated by ToolsAA (reqwest & tokio)
//! Zero-server-upload client-side generation, memory safe and asynchronous.

use reqwest::Client;
use serde::{Deserialize, Serialize};

// ============================================================================
// TYPE-SAFE DATA MODELS (Serde derive)
// ============================================================================

#[derive(Default, Debug, Clone, PartialEq, Serialize, Deserialize)]
pub struct MessagItem {
    pub role: String,
    pub content: String,
}

#[derive(Default, Debug, Clone, PartialEq, Serialize, Deserialize)]
pub struct RequestPayload {
    pub model: String,
    pub temperature: f64,
    pub max_tokens: i64,
    pub stream: bool,
    pub messages: Vec<MessagItem>,
}

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    // Thread-safe reqwest client with internal connection pooling
    let client = Client::new();

    // Construct typed Rust request payload
    let payload = RequestPayload {
        model: "gpt-4o".to_string(),
        temperature: 0.7,
        max_tokens: 1024,
        stream: false,
        messages: vec![
            MessagItem {
                role: "system".to_string(),
                content: "You are an expert Rust systems programmer.".to_string(),
            },
            MessagItem {
                role: "user".to_string(),
                content: "Explain zero-cost abstractions in reqwest and tokio.".to_string(),
            }
        ],
    };

    // Build and dispatch HTTP request
    let response = client.post("https://api.openai.com/v1/chat/completions")
        .bearer_auth("sk-proj-1234567890abcdef")
        .json(&payload)
        .send()
        .await?;

    // Inspect HTTP status code
    let status = response.status();
    println!("Status Code: {}", status);

    // Parse response body as structured JSON
    let json_body: serde_json::Value = response.json().await?;
    println!("Response JSON:\n{:#}", json_body);

    Ok(())
}
HTTP Method
POSThttps://api.openai.com/v1/chat/completions
Target Host
1 Headers
json payload • 0 query params
Headers & Payload
reqwest 0.12 • Tokio 1.x
Zero-Cost Hyper Runtime

100% Client-Side Transpilation

All cURL parsing, argument tokenization, and Rust code generation happen entirely within your browser memory. No credentials or endpoints ever touch an external server.

Async Tokio & reqwest Idioms

Generates modern, asynchronous Rust code using reqwest and the Tokio runtime, featuring ergonomic builder methods, structured headers, and clean error propagation with the ? operator.

Cargo.toml & Full Flag Parity

Automatically synthesizes required Cargo.toml crate dependencies and features, supporting query parameters, Bearer tokens, Basic Auth (-u), multipart forms, timeouts, and custom TLS.

Technical Reference & Architecture Guide

cURL to Rust (reqwest & tokio) Code Generator — Reference Guide

Transform cURL commands into idiomatic, asynchronous Rust HTTP requests using reqwest, serde_json, custom headers, and tokio runtime.

Key Parameters & Controls

clientEnginestring

Target Rust HTTP client architecture: Asynchronous reqwest with Tokio runtime or synchronous reqwest::blocking.

Default: reqwest (async)
jsonParserstring

JSON serialization and deserialization library used for structured request payloads and typed responses (serde_json::Value vs strongly-typed structs).

Default: serde_json
runtimeFlavorstring

Async runtime entry point macro and multi-threaded executor configuration (#[tokio::main] vs custom tokio::runtime::Builder).

Default: #[tokio::main]
cargoTomlOutputboolean

Generates a companion Cargo.toml dependencies manifest snippet containing required crate feature flags like json, multipart, and stream.

Default: true
connectionPoolingboolean

Structures generated code to demonstrate reqwest::Client reuse across tasks to prevent socket exhaustion and enable TCP connection pooling.

Default: true

Pro Tips & Best Practices

reqwest disables optional features

reqwest disables optional features by default to maintain minimal compile times. When sending JSON bodies with .json(&payload) or uploading files with multipart forms, ensure your Cargo.toml specifies reqwest = { version = "0.12", features = ["json", "multipart"] }.

reqwest

reqwest::Client internally wraps an Arc over connection pools and TLS state. Construct a single Client instance during application startup and clone it across async Tokio tasks (client.clone()) instead of instantiating new clients per request, avoiding socket churn and TLS renegotiation.

Avoid calling .unwrap

Avoid calling .unwrap() or .expect() on network calls in production. Define functions returning Result<T, Box<dyn std::error::Error + Send + Sync>> or custom anyhow::Result, allowing the ? operator to propagate connection timeouts and DNS resolution failures cleanly.

For large file uploads

For large file uploads or continuous event streams (SSE), avoid loading entire payloads into memory buffers. Use reqwest::Body::wrap_stream with tokio::io::AsyncRead to stream data incrementally with minimal RAM overhead.

Common Gotchas & Troubleshooting

error[E0599]: no method named `json` found for struct `RequestBuilder` in the current scope

This compile-time error occurs when the 'json' feature flag is missing from your Cargo.toml. Update your dependencies to reqwest = { version = "0.12", features = ["json"] } and serde_json = "1.0".

error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option`

Ensure your main function signature is declared as async fn main() -> Result<(), Box<dyn std::error::Error>> or use anyhow::Result<()>. Alternatively, handle errors explicitly using match or if let Ok(...) constructs.

reqwest::Error: error sending request for url: connection closed before message completed

This typically occurs when HTTP/2 keep-alive connections are prematurely terminated by intermediary proxies or servers. Configure reqwest::Client::builder().http2_keep_alive_timeout(Duration::from_secs(30)).pool_idle_timeout(Duration::from_secs(60)).build() to handle idle connection cleanup gracefully.

Frequently Asked Questions

How does cURL basic authentication (-u user:password) translate to reqwest in Rust?▼

reqwest provides a dedicated .basic_auth("username", Some("password")) builder method that automatically computes the Base64 representation and sets the Authorization: Basic header without manual string formatting.

What is the difference between reqwest async and reqwest::blocking?▼

reqwest async is built on Hyper and the Tokio non-blocking runtime, designed for high-concurrency microservices and async applications. reqwest::blocking provides a synchronous API suitable for simple CLI utilities or background scripts without async runtime dependencies.

How does cURL multipart form-data (-F key=value -F file=@path) map to Rust reqwest?▼

It constructs a reqwest::multipart::Form. Text fields are appended using .text("key", "value"), while files are attached asynchronously using reqwest::multipart::Part::bytes(tokio::fs::read("path").await?).file_name("filename").

How are query parameters (-G --data-urlencode) handled cleanly in Rust?▼

Instead of manual string concatenation, use the .query(&[("key", "value")]) method on RequestBuilder. It accepts arrays, vectors, or hash maps of key-value pairs and handles RFC 3986 percent-encoding automatically.

Does this cURL to Rust conversion tool store my tokens, secrets, or payloads?▼

No. 100% of command parsing, token extraction, AST derivation, and Rust source code synthesis occur strictly in your browser using client-side JavaScript. No network requests are transmitted to our servers.

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