Handle OOM and OOD more gracefully to not spam Sentry with error reports (#434)

- Improvement: Catch Out Of Memory and Out Of Disk exceptions and report back to reqeuster without reporting an error to Sentry
- Improvement: If creating bucket fails when storing and item in the structured cache, log a warning and propagate error to requester without reporting an error to Sentry
- Improvement: Make an explicit flush of the active block written to in blockstore flush
- Improvement: Make sure cache and cas MakeIndexSnapshot does not throw exception on failure which would cause and abnormal termniation at exit

1 files changed, 15 insertions, 2 deletions

diff --git a/src/zenhttp/httpsys.cpp b/src/zenhttp/httpsys.cpp
index 8c1f68ee8..60358d0b0 100644
--- a/src/zenhttp/httpsys.cpp
+++ b/src/zenhttp/httpsys.cpp
@@ -1812,11 +1812,24 @@ InitialRequestHandler::HandleCompletion(ULONG IoResult, ULONG_PTR NumberOfBytesT
 		// Unable to route
 		return new HttpMessageResponseRequest(Transaction(), 404, "No suitable route found"sv);
 	}
+	catch (std::system_error& SystemError)
+	{
+		if (IsOOM(SystemError.code()) || IsOOD(SystemError.code()))
+		{
+			return new HttpMessageResponseRequest(Transaction(), (uint16_t)HttpResponseCode::InsufficientStorage, SystemError.what());
+		}
+
+		ZEN_ERROR("Caught system error exception while handling request: {}", SystemError.what());
+		return new HttpMessageResponseRequest(Transaction(), (uint16_t)HttpResponseCode::InternalServerError, SystemError.what());
+	}
+	catch (std::bad_alloc& BadAlloc)
+	{
+		return new HttpMessageResponseRequest(Transaction(), (uint16_t)HttpResponseCode::InsufficientStorage, BadAlloc.what());
+	}
 	catch (std::exception& ex)
 	{
 		ZEN_ERROR("Caught exception while handling request: '{}'", ex.what());
-
-		return new HttpMessageResponseRequest(Transaction(), 500, ex.what());
+		return new HttpMessageResponseRequest(Transaction(), (uint16_t)HttpResponseCode::InternalServerError, ex.what());
 	}
 }