ESPAsyncWebServer/src/AsyncEventSource.cpp

369 lines
9.8 KiB
C++

/*
Asynchronous WebServer library for Espressif MCUs
Copyright (c) 2016 Hristo Gochkov. All rights reserved.
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "Arduino.h"
#include "AsyncEventSource.h"
static String generateEventMessage(const char *message, const char *event, uint32_t id, uint32_t reconnect){
String ev = "";
if(reconnect){
ev += "retry: ";
ev += String(reconnect);
ev += "\r\n";
}
if(id){
ev += "id: ";
ev += String(id);
ev += "\r\n";
}
if(event != NULL){
ev += "event: ";
ev += String(event);
ev += "\r\n";
}
if(message != NULL){
size_t messageLen = strlen(message);
char * lineStart = (char *)message;
char * lineEnd;
do {
char * nextN = strchr(lineStart, '\n');
char * nextR = strchr(lineStart, '\r');
if(nextN == NULL && nextR == NULL){
size_t llen = ((char *)message + messageLen) - lineStart;
char * ldata = (char *)malloc(llen+1);
if(ldata != NULL){
memcpy(ldata, lineStart, llen);
ldata[llen] = 0;
ev += "data: ";
ev += ldata;
ev += "\r\n\r\n";
free(ldata);
}
lineStart = (char *)message + messageLen;
} else {
char * nextLine = NULL;
if(nextN != NULL && nextR != NULL){
if(nextR < nextN){
lineEnd = nextR;
if(nextN == (nextR + 1))
nextLine = nextN + 1;
else
nextLine = nextR + 1;
} else {
lineEnd = nextN;
if(nextR == (nextN + 1))
nextLine = nextR + 1;
else
nextLine = nextN + 1;
}
} else if(nextN != NULL){
lineEnd = nextN;
nextLine = nextN + 1;
} else {
lineEnd = nextR;
nextLine = nextR + 1;
}
size_t llen = lineEnd - lineStart;
char * ldata = (char *)malloc(llen+1);
if(ldata != NULL){
memcpy(ldata, lineStart, llen);
ldata[llen] = 0;
ev += "data: ";
ev += ldata;
ev += "\r\n";
free(ldata);
}
lineStart = nextLine;
if(lineStart == ((char *)message + messageLen))
ev += "\r\n";
}
} while(lineStart < ((char *)message + messageLen));
}
return ev;
}
// Message
AsyncEventSourceMessage::AsyncEventSourceMessage(const char * data, size_t len)
: _data(nullptr), _len(len), _sent(0), _acked(0)
{
_data = (uint8_t*)malloc(_len+1);
if(_data == nullptr){
_len = 0;
} else {
memcpy(_data, data, len);
_data[_len] = 0;
}
}
AsyncEventSourceMessage::~AsyncEventSourceMessage() {
if(_data != NULL)
free(_data);
}
size_t AsyncEventSourceMessage::ack(size_t len, uint32_t time) {
(void)time;
// If the whole message is now acked...
if(_acked + len > _len){
// Return the number of extra bytes acked (they will be carried on to the next message)
const size_t extra = _acked + len - _len;
_acked = _len;
return extra;
}
// Return that no extra bytes left.
_acked += len;
return 0;
}
size_t AsyncEventSourceMessage::send(AsyncClient *client) {
const size_t len = _len - _sent;
if(client->space() < len){
return 0;
}
size_t sent = client->add((const char *)_data, len);
if(client->canSend())
client->send();
_sent += sent;
return sent;
}
// Client
AsyncEventSourceClient::AsyncEventSourceClient(AsyncWebServerRequest *request, AsyncEventSource *server)
: _messageQueue(LinkedList<AsyncEventSourceMessage *>([](AsyncEventSourceMessage *m){ delete m; }))
{
_client = request->client();
_server = server;
_lastId = 0;
if(request->hasHeader("Last-Event-ID"))
_lastId = atoi(request->getHeader("Last-Event-ID")->value().c_str());
_client->setRxTimeout(0);
_client->onError(NULL, NULL);
_client->onAck([](void *r, AsyncClient* c, size_t len, uint32_t time){ (void)c; ((AsyncEventSourceClient*)(r))->_onAck(len, time); }, this);
_client->onPoll([](void *r, AsyncClient* c){ (void)c; ((AsyncEventSourceClient*)(r))->_onPoll(); }, this);
_client->onData(NULL, NULL);
_client->onTimeout([this](void *r, AsyncClient* c __attribute__((unused)), uint32_t time){ ((AsyncEventSourceClient*)(r))->_onTimeout(time); }, this);
_client->onDisconnect([this](void *r, AsyncClient* c){ ((AsyncEventSourceClient*)(r))->_onDisconnect(); delete c; }, this);
_server->_addClient(this);
delete request;
}
AsyncEventSourceClient::~AsyncEventSourceClient(){
_messageQueue.free();
close();
}
void AsyncEventSourceClient::_queueMessage(AsyncEventSourceMessage *dataMessage){
if(dataMessage == NULL)
return;
if(!connected()){
delete dataMessage;
return;
}
if(_messageQueue.length() >= SSE_MAX_QUEUED_MESSAGES){
ets_printf("ERROR: Too many messages queued\n");
delete dataMessage;
} else {
_messageQueue.add(dataMessage);
}
if(_client->canSend())
_runQueue();
}
void AsyncEventSourceClient::_onAck(size_t len, uint32_t time){
while(len && !_messageQueue.isEmpty()){
len = _messageQueue.front()->ack(len, time);
if(_messageQueue.front()->finished())
_messageQueue.remove(_messageQueue.front());
}
_runQueue();
}
void AsyncEventSourceClient::_onPoll(){
if(!_messageQueue.isEmpty()){
_runQueue();
}
}
void AsyncEventSourceClient::_onTimeout(uint32_t time __attribute__((unused))){
_client->close(true);
}
void AsyncEventSourceClient::_onDisconnect(){
_client = NULL;
_server->_handleDisconnect(this);
}
void AsyncEventSourceClient::close(){
if(_client != NULL)
_client->close();
}
void AsyncEventSourceClient::write(const char * message, size_t len){
_queueMessage(new AsyncEventSourceMessage(message, len));
}
void AsyncEventSourceClient::send(const char *message, const char *event, uint32_t id, uint32_t reconnect){
String ev = generateEventMessage(message, event, id, reconnect);
_queueMessage(new AsyncEventSourceMessage(ev.c_str(), ev.length()));
}
void AsyncEventSourceClient::_runQueue(){
while(!_messageQueue.isEmpty() && _messageQueue.front()->finished()){
_messageQueue.remove(_messageQueue.front());
}
for(auto i = _messageQueue.begin(); i != _messageQueue.end(); ++i)
{
if(!(*i)->sent())
(*i)->send(_client);
}
}
// Handler
AsyncEventSource::AsyncEventSource(const String& url)
: _url(url)
, _clients(LinkedList<AsyncEventSourceClient *>([](AsyncEventSourceClient *c){ delete c; }))
, _connectcb(NULL)
{}
AsyncEventSource::~AsyncEventSource(){
close();
}
void AsyncEventSource::onConnect(ArEventHandlerFunction cb){
_connectcb = cb;
}
void AsyncEventSource::_addClient(AsyncEventSourceClient * client){
/*char * temp = (char *)malloc(2054);
if(temp != NULL){
memset(temp+1,' ',2048);
temp[0] = ':';
temp[2049] = '\r';
temp[2050] = '\n';
temp[2051] = '\r';
temp[2052] = '\n';
temp[2053] = 0;
client->write((const char *)temp, 2053);
free(temp);
}*/
_clients.add(client);
if(_connectcb)
_connectcb(client);
}
void AsyncEventSource::_handleDisconnect(AsyncEventSourceClient * client){
_clients.remove(client);
}
void AsyncEventSource::close(){
for(const auto &c: _clients){
if(c->connected())
c->close();
}
}
// pmb fix
size_t AsyncEventSource::avgPacketsWaiting() const {
if(_clients.isEmpty())
return 0;
size_t aql=0;
uint32_t nConnectedClients=0;
for(const auto &c: _clients){
if(c->connected()) {
aql+=c->packetsWaiting();
++nConnectedClients;
}
}
// return aql / nConnectedClients;
return ((aql) + (nConnectedClients/2))/(nConnectedClients); // round up
}
void AsyncEventSource::send(const char *message, const char *event, uint32_t id, uint32_t reconnect){
String ev = generateEventMessage(message, event, id, reconnect);
for(const auto &c: _clients){
if(c->connected()) {
c->write(ev.c_str(), ev.length());
}
}
}
size_t AsyncEventSource::count() const {
return _clients.count_if([](AsyncEventSourceClient *c){
return c->connected();
});
}
bool AsyncEventSource::canHandle(AsyncWebServerRequest *request){
if(request->method() != HTTP_GET || !request->url().equals(_url)) {
return false;
}
request->addInterestingHeader("Last-Event-ID");
return true;
}
void AsyncEventSource::handleRequest(AsyncWebServerRequest *request){
if((_username != "" && _password != "") && !request->authenticate(_username.c_str(), _password.c_str()))
return request->requestAuthentication();
request->send(new AsyncEventSourceResponse(this));
}
// Response
AsyncEventSourceResponse::AsyncEventSourceResponse(AsyncEventSource *server){
_server = server;
_code = 200;
_contentType = "text/event-stream";
_sendContentLength = false;
addHeader("Cache-Control", "no-cache");
addHeader("Connection","keep-alive");
}
void AsyncEventSourceResponse::_respond(AsyncWebServerRequest *request){
String out = _assembleHead(request->version());
request->client()->write(out.c_str(), _headLength);
_state = RESPONSE_WAIT_ACK;
}
size_t AsyncEventSourceResponse::_ack(AsyncWebServerRequest *request, size_t len, uint32_t time __attribute__((unused))){
if(len){
new AsyncEventSourceClient(request, _server);
}
return 0;
}