Merge pull request #6 from emilmork/supporting-mongoose

Supporting mongoose

Author: lorensr

README.md

@@ -20,6 +20,7 @@ This package uses [DataLoader](https://github.com/graphql/dataloader) for batchi
   - [Basic](#basic)
   - [Batching](#batching)
   - [Caching](#caching)
+  - [Mongoose](#mongoose)
 - [API](#api)
   - [findOneById](#findonebyid)
   - [findManyByIds](#findmanybyids)
@@ -87,6 +88,26 @@ class Users extends MongoDataSource {
 }
 ```
 
+### Mongoose
+
+You can use mongoose the same way as with the native mongodb client
+
+```js
+import mongoose from 'mongoose'
+import Users from './data-sources/Users.js'
+
+const userSchema = new mongoose.Schema({ name: 'string'});
+const UsersModel = mongoose.model('users', userSchema);
+
+const server = new ApolloServer({
+  typeDefs,
+  resolvers,
+  dataSources: () => ({
+    db: new Users({ users: UsersModel })
+  })
+})
+```
+
 ### Batching
 
 This is the main feature, and is always enabled. Here's a full example:

src/cache.js

@@ -1,17 +1,26 @@
 import DataLoader from 'dataloader'
 
+const remapDocs = (docs, ids) => {
+  const idMap = {}
+  docs.forEach(doc => {
+    idMap[doc._id] = doc
+  })
+  return ids.map(id => idMap[id])
+}
+
 export const createCachingMethods = ({ collection, cache }) => {
+  const isMongoose = typeof collection === 'function'
+
   const loader = new DataLoader(ids =>
-    collection
-      .find({ _id: { $in: ids } })
-      .toArray()
-      .then(docs => {
-        const idMap = {}
-        docs.forEach(doc => {
-          idMap[doc._id] = doc
-        })
-        return ids.map(id => idMap[id])
-      })
+    isMongoose
+      ? collection
+          .find({ _id: { $in: ids } })
+          .lean()
+          .then(docs => remapDocs(docs, ids))
+      : collection
+          .find({ _id: { $in: ids } })
+          .toArray()
+          .then(docs => remapDocs(docs, ids))
   )
 
   const cachePrefix = `mongo-${collection.collectionName}-`