Xtykutl

Is there any Java MongoDB library that supports executing native JSON aggregation queries? It seems that MongoTemplate from spring-data-mongo and even MongoClient all require some kind of Java abstraction. But I would like to simply store my queries in external file in JSON format and just execute them without any extra layer of abstraction so they can be simply reused. Similar to native SQL queries.

You can do that with MongoTemplate.

Here's an example of a Spring Repository :

@Autowired

    private MongoTemplate mongoTemplate;



    @PostConstruct

    public void addMarketsToDB() {

        if (mongoTemplate.findOne(new Query(), MarketEntity.class) == null) {

            URL url = this.getClass().getResource("/marches.json");



            byte encoded;

            try {

                encoded = Files.readAllBytes(Paths.get(url.toURI()));



                BasicDBObject obj = new BasicDBObject();

                obj.append("$eval", new String(encoded));



                mongoTemplate.executeCommand(obj);

            } catch (IOException | URISyntaxException e) {

                LOGGER.error("{} addMarketsToDB -> failed to read file", LOG_HEADER);

            }



        }

    }