Function http_request_cb

src/httpserver.cpp:137–198

HTTP request callback */

/** HTTP request callback */
static void http_request_cb(struct evhttp_request *req, void *arg) {
    // NOLINTNEXTLINE(cppcoreguidelines-pro-type-reinterpret-cast)
    Config &config = *reinterpret_cast<Config *>(arg);

    std::shared_ptr<HTTPRequest> hreq { std::make_shared<HTTPRequest>(req) };

    LogPrint(BCLog::HTTP, "Received a %s request for %s from %s\n",
             RequestMethodString(hreq->GetRequestMethod()), hreq->GetURI(),
             hreq->GetPeer().ToString());

    // Early address-based allow check
    if (!ClientAllowed(hreq->GetPeer())) {
        hreq->WriteReply(HTTP_FORBIDDEN);
        return;
    }

    // Early reject unknown HTTP methods
    if (hreq->GetRequestMethod() == HTTPRequest::UNKNOWN) {
        hreq->WriteReply(HTTP_BADMETHOD);
        return;
    }

    // Find registered handler for prefix
    std::string strURI = hreq->GetURI();
    std::string path;
    std::vector<HTTPPathHandler>::const_iterator i = pathHandlers.begin();
    std::vector<HTTPPathHandler>::const_iterator iend = pathHandlers.end();
    for (; i != iend; ++i) {
        bool match = false;
        if (i->exactMatch) {
            match = (strURI == i->prefix);
        } else {
            match = (strURI.substr(0, i->prefix.size()) == i->prefix);
        }
        if (match) {
            path = strURI.substr(i->prefix.size());
            break;
        }
    }

    // Dispatch to worker thread.
    if (i != iend) {
        size_t workQueueDepth = std::max(static_cast<size_t>(gArgs.GetArg("-rpcworkqueue", DEFAULT_HTTP_WORKQUEUE)), size_t{1});

        assert(pWorkQueue);
        if(pWorkQueue->getTaskDepth() < workQueueDepth) {
            auto handleTask = [&config, hreq = std::move(hreq), path, handler = i->handler]()
            {
                handler(config, hreq.get(), path);
            };
            make_task(*pWorkQueue, std::move(handleTask));
        }
        else {
            LogPrintf("WARNING: request rejected because http work queue depth "
                      "exceeded, it can be increased with the -rpcworkqueue= "
                      "setting\n");
            hreq->WriteReply(HTTP_INTERNAL, "Work queue depth exceeded");
        }