Add better support for AS transactions (Fix #97)

- Process transactions async with completion parking
- Detect transactions deduplication

src/main/java/io/kamax/mxisd/config/AsyncConfig.java

@@ -0,0 +1,36 @@
+/*
+ * mxisd - Matrix Identity Server Daemon
+ * Copyright (C) 2018 Kamax Sarl
+ *
+ * https://www.kamax.io/
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program 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 Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package io.kamax.mxisd.config;
+
+import org.springframework.context.annotation.Configuration;
+import org.springframework.web.servlet.config.annotation.AsyncSupportConfigurer;
+import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
+
+@Configuration
+public class AsyncConfig extends WebMvcConfigurerAdapter {
+
+    @Override
+    public void configureAsyncSupport(AsyncSupportConfigurer configurer) {
+        configurer.setDefaultTimeout(60 * 60 * 1000); // 1h in milliseconds
+        super.configureAsyncSupport(configurer);
+    }
+
+}