esp32-sk6812/src/WebServer.cpp

/* HTTP Server setup and handler functions */

#include <SPIFFS.h>

#include "HTTPServer.h"

#include "Fader.h"

HTTPServer::HTTPServer(void)
    : m_fader(NULL)
{
    m_server = new httpsserver::HTTPServer();
}

void HTTPServer::serveFile(String filename, httpsserver::HTTPResponse *res)
{
    uint8_t buf[1024];
    File f = SPIFFS.open(filename.c_str(), "r");

    size_t nread = 1;
    while(nread > 0) {
        nread = f.readBytes(reinterpret_cast<char*>(buf), 1024);
        if(nread <= 0) {
            break;
        }

        res->write(buf, nread);
    }

    f.close();
}

void HTTPServer::handleRoot(httpsserver::HTTPRequest *req, httpsserver::HTTPResponse *res)
{
    serveFile("/index.html", res);
    res->setHeader("Content-Type", "text/html");
}

static void error400(httpsserver::HTTPResponse *res, const std::string &reason)
{
    res->println("Error 400: Bad Request");
    res->println(reason.c_str());

    res->setStatusCode(400);
}

void HTTPServer::handleColor(httpsserver::HTTPRequest *req, httpsserver::HTTPResponse *res)
{
    res->setHeader("Content-Type", "text/plain");

    httpsserver::ResourceParameters * params = req->getParams();

    if(!params->isRequestParameterSet("color")) {
        error400(res, "Parameter 'color' not set.");
        return;
    }

    std::string colorstr = params->getRequestParameter("color");

    if(colorstr.length() != 8) {
        error400(res, "Wrong length of color string (expected 8 hex digits).");
        return;
    }

    uint32_t color = 0;

    for(size_t i = 0; i < 8; i++) {
        color <<= 4;

        char c = colorstr[i];
        if(c >= 'A' && c <= 'F') {
            color |= c - 'A' + 10;
        } else if(c >= 'a' && c <= 'f') {
            color |= c - 'a' + 10;
        } else if(c >= '0' && c <= '9') {
            color |= c - '0';
        } else {
            error400(res, "Invalid character in color string (allowed: 0-9, a-f, A-F)");
            return;
        }
    }

    uint8_t r = (color & 0xFF000000) >> 24;
    uint8_t g = (color & 0x00FF0000) >> 16;
    uint8_t b = (color & 0x0000FF00) >>  8;
    uint8_t w = (color & 0x000000FF) >>  0;

    res->print("Color changed to r:");
    res->print(r);
    res->print(" g:");
    res->print(g);
    res->print(" b:");
    res->print(b);
    res->print(" w:");
    res->println(w);

    HTTPServer::instance().m_fader->fade_color({r,g,b,w});
}

void HTTPServer::handle404(httpsserver::HTTPRequest *req, httpsserver::HTTPResponse *res)
{
    req->discardRequestBody();

    res->setStatusCode(404);
    res->setHeader("Content-Type", "text/plain");

    res->println("Error 404: Not found");
}

void HTTPServer::serverTask(void *arg)
{
    httpsserver::ResourceNode *nodeRoot = new httpsserver::ResourceNode("/", "GET",
                                                                        HTTPServer::handleRoot);
    httpsserver::ResourceNode *nodeColor = new httpsserver::ResourceNode("/color", "GET",
                                                                        HTTPServer::handleColor);
    httpsserver::ResourceNode *node404 = new httpsserver::ResourceNode("", "GET",
                                                                       HTTPServer::handle404);

    HTTPServer &server = HTTPServer::instance();

    server.m_server->registerNode(nodeRoot);
    server.m_server->registerNode(nodeColor);
    server.m_server->setDefaultNode(node404);

    Serial.println("[server] Starting HTTP Server...");
    server.m_server->start();
    if (server.m_server->isRunning())
    {
        Serial.println("[server] Server ready.");

        while (true)
        {
            server.m_server->loop();
        }
    }

    Serial.println("[server] Server died?! This should never happen.");
}

bool HTTPServer::start(void)
{
    xTaskCreate(
        HTTPServer::serverTask, /* Task function. */
        "HTTP Server Task",     /* name of task. */
        6144,                   /* Stack size of task */
        NULL,                   /* parameter of the task */
        1,                      /* priority of the task */
        NULL);                  /* Task handle to keep track of created task */

    return true;
}