chore: Refactoring event processors and service architecture (#2495)

server/tracing.js

@@ -0,0 +1,13 @@
+// @flow
+
+export function initTracing() {
+  // If the DataDog agent is installed and the DD_API_KEY environment variable is
+  // in the environment then we can safely attempt to start the DD tracer
+  if (process.env.DD_API_KEY) {
+    require("dd-trace").init({
+      // SOURCE_COMMIT is used by Docker Hub
+      // SOURCE_VERSION is used by Heroku
+      version: process.env.SOURCE_COMMIT || process.env.SOURCE_VERSION,
+    });
+  }
+}