Struct HttpClient 

pub struct HttpClient<'a, const TCP_RX: usize = MEDIUM_BUFFER_SIZE, const TCP_TX: usize = MEDIUM_BUFFER_SIZE, const TLS_READ: usize = MEDIUM_BUFFER_SIZE, const TLS_WRITE: usize = MEDIUM_BUFFER_SIZE, const RQ: usize = REQUEST_SIZE> { /* private fields */ }

HTTP Client for making HTTP requests with true zero-copy response handling

This is the main client struct for making HTTP requests. It provides methods for performing GET, POST, PUT, DELETE and other HTTP requests using a zero-copy approach where all response data is borrowed directly from user-provided buffers.

The client is designed to work with Embassy’s networking stack and requires users to provide their own response buffers, ensuring maximum memory efficiency and control while maintaining no_std compatibility.

Type Parameters

• TCP_RX - TCP receive buffer size (default: 4096 bytes)
• TCP_TX - TCP transmit buffer size (default: 4096 bytes)
• TLS_READ - TLS read record buffer size (default: 4096 bytes, when TLS feature is enabled)
• TLS_WRITE - TLS write record buffer size (default: 4096 bytes, when TLS feature is enabled)
• RQ - HTTP request buffer size for building requests (default: 1024 bytes)

Implementations

impl<'a, const TCP_RX: usize, const TCP_TX: usize, const TLS_READ: usize, const TLS_WRITE: usize, const RQ: usize> HttpClient<'a, TCP_RX, TCP_TX, TLS_READ, TLS_WRITE, RQ>

pub fn new(stack: &'a Stack<'a>) -> Self

Create a new HTTP client with custom buffer sizes and default options

pub fn with_options(stack: &'a Stack<'a>, options: HttpClientOptions) -> Self

Create a new HTTP client with custom buffer sizes and custom options

pub async fn request<'b>( &self, method: HttpMethod, endpoint: &str, headers: &[HttpHeader<'_>], body: Option<&[u8]>, response_buffer: &'b mut [u8], ) -> Result<(HttpResponse<'b>, usize), Error>

Make an HTTP request with zero-copy response handling

This is the core method for making HTTP requests using zero-copy approach. The caller provides a buffer where the response will be stored, and the returned HttpResponse will contain references to data within that buffer.

Arguments

• method - The HTTP method to use (GET, POST, etc.)
• endpoint - The URL to request (e.g., http://example.com/api)
• headers - A slice of HTTP headers to include in the request
• body - Optional request body data (required for POST/PUT requests)
• response_buffer - A mutable buffer to store the response data

Returns

• Ok((HttpResponse, usize)) - Response with zero-copy body and bytes read
• Err(Error) - Error occurred during the request process

Errors

This function will return an error if:

• The URL is malformed or cannot be parsed
• DNS resolution fails for the hostname
• Network connection cannot be established
• The request times out
• The response cannot be parsed
• The response buffer is too small for the response data

Examples

use nanofish::{DefaultHttpClient, HttpHeader, HttpMethod, ResponseBody};
use embassy_net::Stack;

async fn example(stack: &Stack<'_>) -> Result<(), nanofish::Error> {
    let client = DefaultHttpClient::new(stack);
    let mut buffer = [0u8; 8192]; // You control the buffer size!
    let (response, bytes_read) = client.request(
        HttpMethod::GET,
        "https://example.com",
        &[],
        None,
        &mut buffer
    ).await?;
     
    // Response body now contains direct references to data in buffer
    match response.body {
        ResponseBody::Text(text) => println!("Text: {}", text),
        ResponseBody::Binary(bytes) => println!("Binary: {} bytes", bytes.len()),
        ResponseBody::Empty => println!("Empty response"),
    }
    Ok(())
}

pub async fn patch<'b>( &self, endpoint: &str, headers: &[HttpHeader<'_>], body: &[u8], response_buffer: &'b mut [u8], ) -> Result<(HttpResponse<'b>, usize), Error>

Convenience method for making a PATCH request

Arguments

• endpoint - The URL to request (e.g., http://example.com/api)
• headers - A slice of HTTP headers to include in the request
• body - The request body data

Returns

• Ok(HttpResponse) - Successful response
• Err(Error) - Error occurred during the request process

Errors

Returns the same errors as HttpClient::request.

pub async fn head<'b>( &self, endpoint: &str, headers: &[HttpHeader<'_>], response_buffer: &'b mut [u8], ) -> Result<(HttpResponse<'b>, usize), Error>

Convenience method for making a HEAD request

Arguments

• endpoint - The URL to request (e.g., http://example.com/api)
• headers - A slice of HTTP headers to include in the request

Returns

• Ok(HttpResponse) - Successful response
• Err(Error) - Error occurred during the request process

Errors

Returns the same errors as HttpClient::request.

pub async fn options<'b>( &self, endpoint: &str, headers: &[HttpHeader<'_>], response_buffer: &'b mut [u8], ) -> Result<(HttpResponse<'b>, usize), Error>

Convenience method for making an OPTIONS request

Arguments

• endpoint - The URL to request (e.g., http://example.com/api)
• headers - A slice of HTTP headers to include in the request

Returns

• Ok(HttpResponse) - Successful response
• Err(Error) - Error occurred during the request process

Errors

Returns the same errors as HttpClient::request.

pub async fn trace<'b>( &self, endpoint: &str, headers: &[HttpHeader<'_>], response_buffer: &'b mut [u8], ) -> Result<(HttpResponse<'b>, usize), Error>

Convenience method for making a TRACE request

Arguments

• endpoint - The URL to request (e.g., http://example.com/api)
• headers - A slice of HTTP headers to include in the request

Returns

• Ok(HttpResponse) - Successful response
• Err(Error) - Error occurred during the request process

Errors

Returns the same errors as HttpClient::request.

pub async fn connect<'b>( &self, endpoint: &str, headers: &[HttpHeader<'_>], response_buffer: &'b mut [u8], ) -> Result<(HttpResponse<'b>, usize), Error>

Convenience method for making a CONNECT request

Arguments

• endpoint - The URL to request (e.g., http://example.com/api)
• headers - A slice of HTTP headers to include in the request

Returns

• Ok(HttpResponse) - Successful response
• Err(Error) - Error occurred during the request process

Errors

Returns the same errors as HttpClient::request.

pub async fn get<'b>( &self, endpoint: &str, headers: &[HttpHeader<'_>], response_buffer: &'b mut [u8], ) -> Result<(HttpResponse<'b>, usize), Error>

Convenience method for making a GET request

Arguments

• endpoint - The URL to request (e.g., http://example.com/api)
• headers - A slice of HTTP headers to include in the request

Returns

• Ok(HttpResponse) - Successful response
• Err(Error) - Error occurred during the request process

Errors

Returns the same errors as HttpClient::request.

pub async fn post<'b>( &self, endpoint: &str, headers: &[HttpHeader<'_>], body: &[u8], response_buffer: &'b mut [u8], ) -> Result<(HttpResponse<'b>, usize), Error>

Convenience method for making a POST request

Arguments

• endpoint - The URL to request (e.g., http://example.com/api)
• headers - A slice of HTTP headers to include in the request
• body - The request body data

Returns

• Ok(HttpResponse) - Successful response
• Err(Error) - Error occurred during the request process

Errors

Returns the same errors as HttpClient::request.

pub async fn put<'b>( &self, endpoint: &str, headers: &[HttpHeader<'_>], body: &[u8], response_buffer: &'b mut [u8], ) -> Result<(HttpResponse<'b>, usize), Error>

Convenience method for making a PUT request

Arguments

• endpoint - The URL to request (e.g., http://example.com/api)
• headers - A slice of HTTP headers to include in the request
• body - The request body data

Returns

• Ok(HttpResponse) - Successful response
• Err(Error) - Error occurred during the request process

Errors

Returns the same errors as HttpClient::request.

pub async fn delete<'b>( &self, endpoint: &str, headers: &[HttpHeader<'_>], response_buffer: &'b mut [u8], ) -> Result<(HttpResponse<'b>, usize), Error>

Convenience method for making a DELETE request

Arguments

• endpoint - The URL to request (e.g., http://example.com/api)
• headers - A slice of HTTP headers to include in the request

Returns

• Ok(HttpResponse) - Successful response
• Err(Error) - Error occurred during the request process

Errors

Returns the same errors as HttpClient::request.