fetch.h File Reference

Detailed Description

Unified HTTP fetch API for FastLED (cross-platform)

This API provides both simple callback-based and JavaScript-like promise-based interfaces for HTTP requests. Works on WASM/browser platforms with real fetch, provides stubs on embedded.

WASM Optimization: On WASM platforms, delay() automatically pumps all async tasks (fetch, timers, etc.) in 1ms intervals, making delay time useful for processing async operations.

Callback Usage

#include "fl/fetch.h"
 
void setup() {
    // Simple callback-based fetch (backward compatible)
    fl::fetch("http://fastled.io", [](const fl::response& resp) {
        if (resp.ok()) {
            FL_WARN("Success: " << resp.text());
        }
    });
}

Usage

#include "fl/fetch.h"
 
void setup() {
    // JavaScript-like fetch with promises
    fl::fetch_get("http://fastled.io")
        .then([](const fl::response& resp) {
            if (resp.ok()) {
                FL_WARN("Success: " << resp.text());
            } else {
                FL_WARN("HTTP Error: " << resp.status() << " " << resp.status_text());
            }
        })
        .catch_([](const fl::Error& err) {
            FL_WARN("Fetch Error: " << err.message);
        });
}
 
void loop() {
    // Fetch promises are automatically updated through FastLED's engine events!
    // On WASM platforms, delay() also pumps all async tasks automatically.
    // No manual updates needed - just use normal FastLED loop
    FastLED.show();
    delay(16); // delay() automatically pumps all async tasks on WASM
}

Definition in file fetch.h.

#include "fl/namespace.h"
#include "fl/promise.h"
#include "fl/string.h"
#include "fl/vector.h"
#include "fl/map.h"
#include "fl/hash_map.h"
#include "fl/optional.h"
#include "fl/function.h"
#include "fl/ptr.h"
#include "fl/async.h"
#include "fl/mutex.h"
#include "fl/warn.h"
#include "fl/json.h"

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Classes
class	fl::fetch_options
	Fetch options builder (fluent interface) More...
class	fl::FetchManager
	Internal fetch manager for promise tracking. More...
struct	fl::RequestOptions
	Request options (matches JavaScript fetch RequestInit) More...
class	fl::response
	HTTP response class (unified interface) More...

Namespaces
namespace	fl
	IMPORTANT!

Typedefs
using	fl::FetchCallback = fl::function<void(const response&)>
	Callback type for simple fetch responses (backward compatible)

Functions
fl::promise< response >	fl::execute_fetch_request (const fl::string &url, const fetch_options &request)
	Internal helper to execute a fetch request and return a promise.
void	fl::fetch (const char *url, const FetchCallback &callback)
	Make an HTTP GET request with URL string literal (cross-platform)
void	fl::fetch (const fl::string &url, const FetchCallback &callback)
	Make an HTTP GET request (cross-platform, backward compatible)
fl::size	fl::fetch_active_requests ()
	Get number of active requests.
fl::promise< response >	fl::fetch_delete (const fl::string &url, const fetch_options &request=fetch_options(""))
	HTTP DELETE request.
fl::promise< response >	fl::fetch_get (const fl::string &url, const fetch_options &request=fetch_options(""))
	HTTP GET request.
fl::promise< response >	fl::fetch_head (const fl::string &url, const fetch_options &request=fetch_options(""))
	HTTP HEAD request.
fl::promise< response >	fl::fetch_http_options (const fl::string &url, const fetch_options &request=fetch_options(""))
	HTTP OPTIONS request.
fl::promise< response >	fl::fetch_patch (const fl::string &url, const fetch_options &request=fetch_options(""))
	HTTP PATCH request.
fl::promise< response >	fl::fetch_post (const fl::string &url, const fetch_options &request=fetch_options(""))
	HTTP POST request.
fl::promise< response >	fl::fetch_put (const fl::string &url, const fetch_options &request=fetch_options(""))
	HTTP PUT request.
fl::promise< response >	fl::fetch_request (const fl::string &url, const RequestOptions &options=RequestOptions())
	Generic request with options (like fetch(url, options))
void	fl::fetch_update ()
	Legacy manual update for fetch promises (use fl::async_run() for new code)