Add case insensitive indexes support

README.md

@@ -70,6 +70,7 @@ of type `GeoPoint`. This allows for indexed ```near``` queries.  Default is `fal
   - It will try to establish the connection automatically once users hit the endpoint. If the mongodb server is offline, the app will start, however, the endpoints will not work.
 - **disableDefaultSort**: Set to `true` to disable the default sorting
   behavior on `id` column, this will help performance using indexed columns available in mongodb.
+- **collation**: Specify language-specific rules for string comparison, such as rules for lettercase and accent marks. See [`MongdoDB documentation`](https://docs.mongodb.com/manual/reference/collation/) for details. It can also be used to create [`case insensitive indexes`](https://docs.mongodb.com/manual/core/index-case-insensitive/).
 
 ### Setting the url property in datasource.json
 

lib/mongodb.js

@@ -1315,6 +1315,11 @@ MongoDB.prototype.all = function all(model, filter, options, callback) {
       return callback(err);
     }
 
+    var collation = options && options.collation;
+    if (collation) {
+      cursor.collation(collation);
+    }
+
     // don't apply sorting if dealing with a geo query
     if (!hasNearFilter(filter.where)) {
       var order = self.buildSort(model, filter.order, options);

test/mongodb.test.js

@@ -255,6 +255,13 @@ describe('mongodb connector', function() {
     Category = db.define('Category', {
       title: {type: String, length: 255, index: true},
       posts: {type: [db.ObjectID], index: true},
+    }, {
+      indexes: {
+        'title_case_insensitive': {
+          keys: {title: 1},
+          options: {collation: {locale: 'en', strength: 1}},
+        },
+      },
     });
 
     PostWithStringIdAndRenamedColumns = db.define(
@@ -314,7 +321,9 @@ describe('mongodb connector', function() {
             PostWithNumberUnderscoreId.destroyAll(function() {
               PostWithStringId.destroyAll(function() {
                 PostWithDisableDefaultSort.destroyAll(function() {
-                  done();
+                  Category.destroyAll(function() {
+                    done();
+                  });
                 });
               });
             });
@@ -508,6 +517,23 @@ describe('mongodb connector', function() {
     });
   });
 
+  it('should create case insensitive indexes', function(done) {
+    db.automigrate('Category', function() {
+      db.connector.db.collection('Category').indexes(function(err, result) {
+        if (err) return done(err);
+        var indexes = [
+          {name: '_id_', key: {_id: 1}},
+          {name: 'title_1', key: {title: 1}},
+          {name: 'title_case_insensitive', key: {title: 1}, collation: {locale: 'en', strength: 1}},
+          {name: 'posts_1', key: {posts: 1}},
+        ];
+
+        result.should.containDeep(indexes);
+        done();
+      });
+    });
+  });
+
   it('should have created models with correct _id types', function(done) {
     PostWithObjectId.definition.properties._id.type.should.be.equal(
       db.ObjectID
@@ -2679,6 +2705,22 @@ describe('mongodb connector', function() {
     });
   });
 
+  it('should allow to find using case insensitive index', function(done) {
+    Category.create({title: 'My Category'}, function(err, category1) {
+      if (err) return done(err);
+      Category.create({title: 'MY CATEGORY'}, function(err, category2) {
+        if (err) return done(err);
+
+        Category.find({where: {title: 'my cATEGory'}}, {collation: {locale: 'en', strength: 1}},
+          function(err, categories) {
+            if (err) return done(err);
+            categories.should.have.length(2);
+            done();
+          });
+      });
+    });
+  });
+
   it('should allow to find using like', function(done) {
     Post.create({title: 'My Post', content: 'Hello'}, function(err, post) {
       Post.find({where: {title: {like: 'M.+st'}}}, function(err, posts) {