Log errors if too less memory for webapi is available

include/WebApi.h

@@ -31,6 +31,8 @@ public:
     static bool checkCredentials(AsyncWebServerRequest* request);
     static bool checkCredentialsReadonly(AsyncWebServerRequest* request);
 
+    static void sendTooManyRequests(AsyncWebServerRequest* request);
+
 private:
     AsyncWebServer _server;
     AsyncEventSource _events;

src/WebApi.cpp

@@ -90,4 +90,11 @@ bool WebApiClass::checkCredentialsReadonly(AsyncWebServerRequest* request)
     }
 }
 
+void WebApiClass::sendTooManyRequests(AsyncWebServerRequest* request)
+{
+    auto response = request->beginResponse(429, "text/plain", "Too Many Requests");
+    response->addHeader("Retry-After", "60");
+    request->send(response);
+}
+
 WebApiClass WebApi;

src/WebApi_prometheus.cpp

@@ -5,7 +5,9 @@
  */
 #include "WebApi_prometheus.h"
 #include "Configuration.h"
+#include "MessageOutput.h"
 #include "NetworkSettings.h"
+#include "WebApi.h"
 #include <Hoymiles.h>
 
 void WebApiPrometheusClass::init(AsyncWebServer* server)
@@ -23,6 +25,7 @@ void WebApiPrometheusClass::loop()
 
 void WebApiPrometheusClass::onPrometheusMetricsGet(AsyncWebServerRequest* request)
 {
+    try {
         auto stream = request->beginResponseStream("text/plain; charset=utf-8", 40960);
 
         stream->print(F("# HELP opendtu_build Build info\n"));
@@ -88,6 +91,12 @@ void WebApiPrometheusClass::onPrometheusMetricsGet(AsyncWebServerRequest* reques
         }
         stream->addHeader(F("Cache-Control"), F("no-cache"));
         request->send(stream);
+
+    } catch (std::bad_alloc& bad_alloc) {
+        MessageOutput.printf("Call to /api/prometheus/metrics temporarely out of resources. Reason: \"%s\".\r\n", bad_alloc.what());
+
+        WebApi.sendTooManyRequests(request);
+    }
 }
 
 void WebApiPrometheusClass::addField(AsyncResponseStream* stream, String& serial, uint8_t idx, std::shared_ptr<InverterAbstract> inv, ChannelType_t type, ChannelNum_t channel, FieldId_t fieldId, const char* channelName)

src/WebApi_ws_live.cpp

@@ -60,6 +60,7 @@ void WebApiWsLiveClass::loop()
     // Update on every inverter change or at least after 10 seconds
     if (millis() - _lastWsPublish > (10 * 1000) || (maxTimeStamp != _newestInverterTimestamp)) {
 
+        try {
             DynamicJsonDocument root(40960);
             JsonVariant var = root;
             generateJsonResponse(var);
@@ -77,6 +78,10 @@ void WebApiWsLiveClass::loop()
                 _ws.textAll(buffer);
             }
 
+        } catch (std::bad_alloc& bad_alloc) {
+            MessageOutput.printf("Call to /api/livedata/status temporarely out of resources. Reason: \"%s\".\r\n", bad_alloc.what());
+        }
+
         _lastWsPublish = millis();
     }
 }
@@ -220,6 +225,7 @@ void WebApiWsLiveClass::onLivedataStatus(AsyncWebServerRequest* request)
         return;
     }
 
+    try {
         AsyncJsonResponse* response = new AsyncJsonResponse(false, 40960U);
         JsonVariant root = response->getRoot();
 
@@ -227,4 +233,10 @@ void WebApiWsLiveClass::onLivedataStatus(AsyncWebServerRequest* request)
 
         response->setLength();
         request->send(response);
+
+    } catch (std::bad_alloc& bad_alloc) {
+        MessageOutput.printf("Call to /api/livedata/status temporarely out of resources. Reason: \"%s\".\r\n", bad_alloc.what());
+
+        WebApi.sendTooManyRequests(request);
+    }
 }