Extract dispatch from router

js/server/modules/@arangodb/foxx/router/router.js

@@ -140,20 +140,6 @@ module.exports = class Router extends SwaggerContext {
     const root = new Map();
     this._tree = root;
 
-    // middleware always implicitly ends in a wildcard
-    // child routers always explicitly end in wildcards
-    // routes may explicitly end in a wildcard
-    // static names have precedence over params
-    // params have precedence over wildcards
-    // middleware is executed in order of precedence
-    // implicit 404 in middleware does not fail the routing
-    // router.all ONLY affects routes of THAT router (and its children)
-    // * router.all does NOT affect routes of sibling routers *
-
-    // should child routers have precedence over routes?
-    // ideally they should respect each others precedence
-    // and be treated equally
-
     for (let middleware of this._middleware) {
       let node = root;
       for (let token of middleware._pathTokens) {
@@ -186,13 +172,6 @@ module.exports = class Router extends SwaggerContext {
     }
   }
 
-  * _traverse(suffix) {
-    let result = [{router: this, path: [], suffix: suffix}];
-    for (let route of traverse(this._tree, result, suffix, [])) {
-      yield route;
-    }
-  }
-
   _dispatch(rawReq, rawRes, context) {
     let route = resolve(this, rawReq);
 
@@ -200,12 +179,25 @@ module.exports = class Router extends SwaggerContext {
       return false;
     }
 
-    let pathParams = {};
-    let queryParams = _.clone(rawReq.queryParams);
-
     const req = new SyntheticRequest(rawReq, context);
     const res = new SyntheticResponse(rawRes);
 
+    dispatch(route, req, res);
+    return true;
+  }
+
+  * _traverse(suffix) {
+    let result = [{router: this, path: [], suffix: suffix}];
+    for (let route of traverse(this._tree, result, suffix, [])) {
+      yield route;
+    }
+  }
+};
+
+function dispatch(route, req, res) {
+  let pathParams = {};
+  let queryParams = _.clone(req.queryParams);
+
   function next(err) {
     if (err) {
       throw err;
@@ -249,9 +241,7 @@ module.exports = class Router extends SwaggerContext {
   }
 
   next();
-    return true;
-  }
-};
+}
 
 function applyPathParams(route) {
   for (const item of route) {