kbf/src/http/server.cpp

#include "kbf/http/server.h"

#include <esp_log.h>
#include <esp_https_server.h>
#include <memory>

#include "kbf/macros.h"

using namespace kbf;

http::Server &http::Server::route(http::Server::Route route) {
    ESP_LOGD(TAG, "adding route: %s", route.uri.c_str());
    routes.push_back(route);
    return *this;
}

http::Server &http::Server::start(int port) {
    ESP_LOGI(TAG, "start(%d)", port);
    if (running) {
        ESP_LOGE(TAG, "server already running");
        ABORT("fix me");
    }

    handle = nullptr;
    httpd_config_t config = HTTPD_DEFAULT_CONFIG();
    config.server_port = port;
    config.stack_size  = 16384;
    CHECK(httpd_start(&handle, &config));

    registerUriHandlers();

    running = true;
    return *this;
}

http::Server &http::Server::startSSL(int port) {
    ESP_LOGI(TAG, "startSSL(%d)", port);
    if (running) {
        ESP_LOGE(TAG, "server already running");
        ABORT("fix me");
    }

    handle = nullptr;
    httpd_ssl_config_t conf = HTTPD_SSL_CONFIG_DEFAULT();

    extern const unsigned char cacert_pem_start[] asm("_binary_cacert_pem_start");
    extern const unsigned char cacert_pem_end[]   asm("_binary_cacert_pem_end");
    conf.cacert_pem = cacert_pem_start;
    conf.cacert_len = cacert_pem_end - cacert_pem_start;

    extern const unsigned char prvtkey_pem_start[] asm("_binary_prvtkey_pem_start");
    extern const unsigned char prvtkey_pem_end[]   asm("_binary_prvtkey_pem_end");
    conf.prvtkey_pem = prvtkey_pem_start;
    conf.prvtkey_len = prvtkey_pem_end - prvtkey_pem_start;

    CHECK(httpd_ssl_start(&handle, &conf));

    registerUriHandlers();

    running = true;
    return *this;
}

void http::Server::registerUriHandlers() {
    ESP_LOGI(TAG, "registering URI handlers");
    for (auto &route : routes) {
        ESP_LOGI(TAG, "  method: %d; uri: %s", static_cast<int>(route.method), route.uri.c_str());
        httpd_uri_t uriHandler = {
                .uri = route.uri.c_str(),
                .method = static_cast<httpd_method_t>(route.method),
                .handler = handleHttpRequest,
                .user_ctx = &route
        };
        CHECK(httpd_register_uri_handler(handle, &uriHandler));
    }
}

void http::Server::stop() {
    CHECK(httpd_stop(handle));
    running = false;
}

// TODO handle all status codes; also maybe use macro or constexpr or something?
static string getDefaultStatusText(int status) {
    if (status == 200) return "OK";
    if (status == 204) return "No Content";
    if (status == 400) return "Bad Request";
    if (status == 500) return "Internal Server Error";
    return "Unknown HTTP Status";
}

esp_err_t http::Server::handleHttpRequest(httpd_req_t *httpdRequest) {
    auto route = static_cast<Route *>(httpdRequest->user_ctx);
    ESP_LOGD(TAG, "handleHttpRequest; method: %d, path: \"%s\"", httpdRequest->method, route->uri.c_str());

    auto request  = Request(httpdRequest);
    auto response = route->handler(request, route->data);

    CHECK(httpd_resp_set_hdr(httpdRequest, "Server", "kbf_http_server/0.1"));
    CHECK(httpd_resp_set_type(httpdRequest, response.contentType.c_str()));
    for (const auto &[name, value] : response.headers) {
        CHECK(httpd_resp_set_hdr(httpdRequest, name.c_str(), value.c_str()));
    }

    if (response.statusText.empty()) {
        response.statusText = getDefaultStatusText(response.status);
    }

    string status = std::to_string(response.status) + " " + response.statusText;
    ESP_LOGD(TAG, "response: %s", status.c_str());
    CHECK(httpd_resp_set_status(httpdRequest, status.c_str()));

    ESP_LOG_BUFFER_HEXDUMP(TAG, response.body.c_str(), response.body.size(), ESP_LOG_VERBOSE);

    auto err = httpd_resp_send(httpdRequest, response.body.c_str(), response.body.length());
    if (err == ESP_ERR_HTTPD_RESP_SEND) {
        ESP_LOGW(TAG, "send failed; maybe client disconnected?");
        return ESP_ERR_HTTPD_RESP_SEND;
    }
    CHECK(err);
    return ESP_OK;
}

http::Server::~Server() {
    if (running) stop();
}