From 6f0ad678eb91b9c089d71f67bf6a8cf4a1abf39e Mon Sep 17 00:00:00 2001
From: Julian Simioni <julian@simioni.org>
Date: Fri, 4 Sep 2015 15:54:25 -0400
Subject: [PATCH] Add types middleware

This middleware looks at the list of types that will be sent to
Elasticsearch, if it's an empty array, it sends an error response before
Elasticsearch is even quieried, because Elasticsearch interprets an
empty type array as "search anything" rather than the intended "don't
search anything".
---
 controller/search.js |  9 +++------
 middleware/_types.js | 27 +++++++++++++++++++++++++++
 routes/v1.js         |  6 ++++++
 sanitiser/search.js  |  1 +
 4 files changed, 37 insertions(+), 6 deletions(-)
 create mode 100644 middleware/_types.js

diff --git a/controller/search.js b/controller/search.js
index c353c5be..d70c1b5c 100644
--- a/controller/search.js
+++ b/controller/search.js
@@ -1,5 +1,4 @@
 var service = { search: require('../service/search') };
-var types = require ( '../helper/types' );
 
 function setup( backend, query ){
 
@@ -16,11 +15,9 @@ function setup( backend, query ){
       body: query( req.clean )
     };
 
-    // don't directly set cmd.type from types helper to avoid sometimes
-    // setting cmd.type to undefined (having the key not set is cleaner)
-    var type = types(req.clean.types);
-    if (type !== undefined) {
-      cmd.type = type;
+    if (req.clean.type !== undefined) {
+      cmd.type = req.clean.type;
+      delete req.clean.type; // remove type from clean to avoid clutter
     }
 
     // query backend
diff --git a/middleware/_types.js b/middleware/_types.js
new file mode 100644
index 00000000..8b12719f
--- /dev/null
+++ b/middleware/_types.js
@@ -0,0 +1,27 @@
+var types_helper = require( '../helper/types' );
+
+/**
+ * Validate the types specified to be searched.
+ *
+ * Elasticsearch interprets an empty array of types as "search anything" rather
+ * than "search nothing", so in the case of an empty array, return an error
+ * message instead of searching at all.
+ */
+function middleware(req, res, next) {
+  var types = types_helper(req.clean.types);
+
+  if (types !== undefined && types.length !== undefined) {
+   if (types.length === 0) {
+    var err = 'You have specified both the `source` and `layers` ' +
+    'parameters in a combination that will return no results.';
+    res.status(400); // 400 Bad Request
+    return next(err);
+   } else {
+     req.clean.type = types;
+   }
+  }
+
+  next();
+}
+
+module.exports = middleware;
diff --git a/routes/v1.js b/routes/v1.js
index cb3b53e2..d5a1c183 100644
--- a/routes/v1.js
+++ b/routes/v1.js
@@ -8,6 +8,11 @@ var sanitisers = {
   reverse: require('../sanitiser/reverse')
 };
 
+/** ----------------------- middleware ------------------------ **/
+var middleware = {
+  types: require('../middleware/_types')
+};
+
 /** ----------------------- controllers ----------------------- **/
 
 var controllers     = {
@@ -40,6 +45,7 @@ function addRoutes(app, peliasConfig) {
     ]),
     search: createRouter([
       sanitisers.search.middleware,
+      middleware.types,
       controllers.search(),
       postProc.renamePlacenames(),
       postProc.geocodeJSON(peliasConfig),
diff --git a/sanitiser/search.js b/sanitiser/search.js
index d226dbd9..17409587 100644
--- a/sanitiser/search.js
+++ b/sanitiser/search.js
@@ -4,6 +4,7 @@ var _sanitize = require('../sanitiser/_sanitize'),
       input: require('../sanitiser/_input'),
       size: require('../sanitiser/_size'),
       layers: require('../sanitiser/_layers'),
+      source: require('../sanitiser/_source'),
       details: require('../sanitiser/_details'),
       latlonzoom: require('../sanitiser/_geo')
     };