#218 - Add GridFS example for Spring Data MongoDB.

Original pull request: #229.

mongodb/gridfs/README.md

@@ -0,0 +1,39 @@
+# Spring Data MongoDB - GridFS example
+
+This project contains an example of [GridFS](https://docs.mongodb.com/v3.4/core/gridfs/) specific features of Spring Data (MongoDB).
+
+## Support for storing a file
+
+Using [GridFsOperations](http://docs.spring.io/spring-data/mongodb/docs/current/api/org/springframework/data/mongodb/gridfs/GridFsOperations.html) to store a file.
+
+```java
+InputStream is = ...
+gridFsOperations.store(is, "myFile1.txt");
+```
+
+## Support for query a file by name
+
+Using [GridFsOperations](http://docs.spring.io/spring-data/mongodb/docs/current/api/org/springframework/data/mongodb/gridfs/GridFsOperations.html) to query a GridFSDBFile by its filename.
+
+```java
+GridFSDBFile gridFsFile = gridFsOperations.findOne(query(whereFilename().is("myFile1.txt")));
+```
+
+## Support for storing a file with metadata
+
+Using [GridFsOperations](http://docs.spring.io/spring-data/mongodb/docs/current/api/org/springframework/data/mongodb/gridfs/GridFsOperations.html) to store a file with additional metadata..
+
+```java
+InputStream is = ...
+Customer customerMetaData = new Customer("Hardy", "Lang");
+gridFsOperations.store(is, "myCustomerFile.txt", customerMetaData);
+
+```
+
+## Support for query a file by metadata
+
+Using [GridFsOperations](http://docs.spring.io/spring-data/mongodb/docs/current/api/org/springframework/data/mongodb/gridfs/GridFsOperations.html) to query a GridFSDBFile by metadata.
+
+```java
+GridFSDBFile gridFsFile = gridFsOperations.findOne(query(whereMetaData("firstName").is("Hardy")));
+```