diff options
| author | schererleander <leander@schererleander.de> | 2026-01-20 08:34:54 +0100 |
|---|---|---|
| committer | schererleander <leander@schererleander.de> | 2026-01-20 08:34:54 +0100 |
| commit | 85ea4e995a75abe061f6fc375ea0481084dddd43 (patch) | |
| tree | 7eb5d57653ecd8f041aeac4e68d7d554c1168681 /libraries/ESP_Async_WebServer/examples/SlowChunkResponse/SlowChunkResponse.ino | |
Diffstat (limited to 'libraries/ESP_Async_WebServer/examples/SlowChunkResponse/SlowChunkResponse.ino')
| -rw-r--r-- | libraries/ESP_Async_WebServer/examples/SlowChunkResponse/SlowChunkResponse.ino | 152 |
1 files changed, 152 insertions, 0 deletions
diff --git a/libraries/ESP_Async_WebServer/examples/SlowChunkResponse/SlowChunkResponse.ino b/libraries/ESP_Async_WebServer/examples/SlowChunkResponse/SlowChunkResponse.ino new file mode 100644 index 0000000..bbf70b6 --- /dev/null +++ b/libraries/ESP_Async_WebServer/examples/SlowChunkResponse/SlowChunkResponse.ino @@ -0,0 +1,152 @@ +// SPDX-License-Identifier: LGPL-3.0-or-later +// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov + +// +// Simulate a slow response in a chunk response (like file download from SD Card) +// poll events will be throttled. +// + +#include <Arduino.h> +#ifdef ESP32 +#include <AsyncTCP.h> +#include <WiFi.h> +#elif defined(ESP8266) +#include <ESP8266WiFi.h> +#include <ESPAsyncTCP.h> +#elif defined(TARGET_RP2040) || defined(TARGET_RP2350) || defined(PICO_RP2040) || defined(PICO_RP2350) +#include <RPAsyncTCP.h> +#include <WiFi.h> +#endif + +#include <ESPAsyncWebServer.h> + +static AsyncWebServer server(80); + +static const char *htmlContent PROGMEM = R"( +<!DOCTYPE html> +<html> +<head> + <title>Sample HTML</title> +</head> +<body> + <h1>Hello, World!</h1> + <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Proin euismod, purus a euismod + rhoncus, urna ipsum cursus massa, eu dictum tellus justo ac justo. Quisque ullamcorper + arcu nec tortor ullamcorper, vel fermentum justo fermentum. Vivamus sed velit ut elit + accumsan congue ut ut enim. Ut eu justo eu lacus varius gravida ut a tellus. Nulla facilisi. + Integer auctor consectetur ultricies. Fusce feugiat, mi sit amet bibendum viverra, orci leo + dapibus elit, id varius sem dui id lacus.</p> + <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Proin euismod, purus a euismod + rhoncus, urna ipsum cursus massa, eu dictum tellus justo ac justo. Quisque ullamcorper + arcu nec tortor ullamcorper, vel fermentum justo fermentum. Vivamus sed velit ut elit + accumsan congue ut ut enim. Ut eu justo eu lacus varius gravida ut a tellus. Nulla facilisi. + Integer auctor consectetur ultricies. Fusce feugiat, mi sit amet bibendum viverra, orci leo + dapibus elit, id varius sem dui id lacus.</p> + <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Proin euismod, purus a euismod + rhoncus, urna ipsum cursus massa, eu dictum tellus justo ac justo. Quisque ullamcorper + arcu nec tortor ullamcorper, vel fermentum justo fermentum. Vivamus sed velit ut elit + accumsan congue ut ut enim. Ut eu justo eu lacus varius gravida ut a tellus. Nulla facilisi. + Integer auctor consectetur ultricies. Fusce feugiat, mi sit amet bibendum viverra, orci leo + dapibus elit, id varius sem dui id lacus.</p> + <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Proin euismod, purus a euismod + rhoncus, urna ipsum cursus massa, eu dictum tellus justo ac justo. Quisque ullamcorper + arcu nec tortor ullamcorper, vel fermentum justo fermentum. Vivamus sed velit ut elit + accumsan congue ut ut enim. Ut eu justo eu lacus varius gravida ut a tellus. Nulla facilisi. + Integer auctor consectetur ultricies. Fusce feugiat, mi sit amet bibendum viverra, orci leo + dapibus elit, id varius sem dui id lacus.</p> + <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Proin euismod, purus a euismod + rhoncus, urna ipsum cursus massa, eu dictum tellus justo ac justo. Quisque ullamcorper + arcu nec tortor ullamcorper, vel fermentum justo fermentum. Vivamus sed velit ut elit + accumsan congue ut ut enim. Ut eu justo eu lacus varius gravida ut a tellus. Nulla facilisi. + Integer auctor consectetur ultricies. Fusce feugiat, mi sit amet bibendum viverra, orci leo + dapibus elit, id varius sem dui id lacus.</p> + <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Proin euismod, purus a euismod + rhoncus, urna ipsum cursus massa, eu dictum tellus justo ac justo. Quisque ullamcorper + arcu nec tortor ullamcorper, vel fermentum justo fermentum. Vivamus sed velit ut elit + accumsan congue ut ut enim. Ut eu justo eu lacus varius gravida ut a tellus. Nulla facilisi. + Integer auctor consectetur ultricies. Fusce feugiat, mi sit amet bibendum viverra, orci leo + dapibus elit, id varius sem dui id lacus.</p> + <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Proin euismod, purus a euismod + rhoncus, urna ipsum cursus massa, eu dictum tellus justo ac justo. Quisque ullamcorper + arcu nec tortor ullamcorper, vel fermentum justo fermentum. Vivamus sed velit ut elit + accumsan congue ut ut enim. Ut eu justo eu lacus varius gravida ut a tellus. Nulla facilisi. + Integer auctor consectetur ultricies. Fusce feugiat, mi sit amet bibendum viverra, orci leo + dapibus elit, id varius sem dui id lacus.</p> + <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Proin euismod, purus a euismod + rhoncus, urna ipsum cursus massa, eu dictum tellus justo ac justo. Quisque ullamcorper + arcu nec tortor ullamcorper, vel fermentum justo fermentum. Vivamus sed velit ut elit + accumsan congue ut ut enim. Ut eu justo eu lacus varius gravida ut a tellus. Nulla facilisi. + Integer auctor consectetur ultricies. Fusce feugiat, mi sit amet bibendum viverra, orci leo + dapibus elit, id varius sem dui id lacus.</p> +</body> +</html> +)"; + +static const size_t htmlContentLength = strlen_P(htmlContent); +static constexpr char characters[] = "0123456789ABCDEF"; +static size_t charactersIndex = 0; + +void setup() { + Serial.begin(115200); + +#ifndef CONFIG_IDF_TARGET_ESP32H2 + WiFi.mode(WIFI_AP); + WiFi.softAP("esp-captive"); +#endif + + // curl -v http://192.168.4.1/ + server.on("/", HTTP_GET, [](AsyncWebServerRequest *request) { + // need to cast to uint8_t* + // if you do not, the const char* will be copied in a temporary String buffer + request->send(200, "text/html", (uint8_t *)htmlContent, htmlContentLength); + }); + + // IMPORTANT - DO NOT WRITE SUCH CODE IN PRODUCTON ! + // + // This example simulates the slowdown that can happen when: + // - downloading a huge file from sdcard + // - doing some file listing on SDCard because it is horribly slow to get a file listing with file stats on SDCard. + // So in both cases, ESP would deadlock or TWDT would trigger. + // + // This example simulats that by slowing down the chunk callback: + // - d=2000 is the delay in ms in the callback + // - l=10000 is the length of the response + // + // time curl -N -v -G -d 'd=2000' -d 'l=10000' http://192.168.4.1/slow.html --output - + // + server.on("/slow.html", HTTP_GET, [](AsyncWebServerRequest *request) { + uint32_t d = request->getParam("d")->value().toInt(); + uint32_t l = request->getParam("l")->value().toInt(); + Serial.printf("d = %" PRIu32 ", l = %" PRIu32 "\n", d, l); + AsyncWebServerResponse *response = request->beginChunkedResponse("text/html", [d, l](uint8_t *buffer, size_t maxLen, size_t index) -> size_t { + Serial.printf("%u\n", index); + // finished ? + if (index >= l) { + return 0; + } + + // slow down the task to simulate some heavy processing, like SD card reading + delay(d); + + memset(buffer, characters[charactersIndex], 256); + charactersIndex = (charactersIndex + 1) % sizeof(characters); + return 256; + }); + + request->send(response); + }); + + server.begin(); +} + +static uint32_t lastHeap = 0; + +void loop() { +#ifdef ESP32 + uint32_t now = millis(); + if (now - lastHeap >= 2000) { + Serial.printf("Free heap: %" PRIu32 "\n", ESP.getFreeHeap()); + lastHeap = now; + } +#endif +} |