loolwsd: flush trace file on events

This reduces chances of data loss and gives
more up-to-date data to the user.

Also include tile messages in the trace recording,
since they are useful for debugging. Should be
disabled to reduce excessive trace generation.

Change-Id: I223144660698843f4e94564e049883db898c0064
Reviewed-on: https://gerrit.libreoffice.org/29060
Reviewed-by: Ashod Nakashian <ashnakash@gmail.com>
Tested-by: Ashod Nakashian <ashnakash@gmail.com>

loolwsd/TraceFile.hpp

@@ -71,6 +71,7 @@ public:
     void writeEvent(const std::string& pId, const std::string& sessionId, const std::string& data)
     {
         write(pId, sessionId, data, static_cast<char>(TraceFileRecord::Direction::Event));
+        flush();
     }
 
     void writeIncoming(const std::string& pId, const std::string& sessionId, const std::string& data)
@@ -89,6 +90,12 @@ public:
         }
     }
 
+    void flush()
+    {
+        _deflater.flush();
+        _stream.flush();
+    }
+
 private:
     void write(const std::string& pId, const std::string& sessionId, const std::string& data, const char delim)
     {

loolwsd/loolwsd.xml.in

@@ -36,7 +36,7 @@
     <trace desc="Dump commands and notifications for replay" enable="true">
         <path desc="Output file path" compress="true">/tmp/looltrace.gz</path>
         <filter>
-            <message desc="Regex pattern of messages to exclude">tile.*</message>
+            <message desc="Regex pattern of messages to exclude"></message>
         </filter>
         <outgoing>
             <record desc="Whether or not to record outgoing messages" default="false">false</record>