I know that there's probably a better way to do this however I'm completely stumped. I'm writing a Discord bot in which a user is able to add points to other users, however I can't figure out how to replace a user's "points". My code is as follows:
BasicDBObject cursor = new BasicDBObject();
cursor.put(user.getAsMember().getId(), getMongoPoints(user.getAsMember()));
if(cursor.containsKey(user.getAsMember().getId())) {
Document old = new Document(user.getAsMember().getId(), getMongoPoints(user.getAsMember()));
Document doc = new Document(user.getAsMember().getId(), getMongoPoints(user.getAsMember()) + Integer.parseInt(amount.getAsString()));
collection.findOneAndUpdate(old, doc);
}
My getMongoPoints function:
public static int getMongoPoints(Member m) {
ConnectionString connectionString = new ConnectionString("database");
MongoClientSettings settings = MongoClientSettings.builder()
.applyConnectionString(connectionString)
.build();
MongoClient mongoClient = MongoClients.create(settings);
MongoDatabase database = mongoClient.getDatabase("SRU");
MongoCollection<Document> collection = database.getCollection("points");
DistinctIterable<Integer> docs = collection.distinct(m.getId(), Integer.class);
MongoCursor<Integer> result = docs.iterator();
return result.next();
}
I've tried findOneAndReplace, however that simply makes a new entry without deleting the old one. The error I receive is: Invalid BSON field name 262014495440896000
Everything else works, include writing to the database itself which is why I'm stumped. Any help would be greatly appreciated and I apologize if this is written poorly.
BSON field names must be string. From the spec:
Zero or more modified UTF-8 encoded characters followed by '\x00'. The (byte*) MUST NOT contain '\x00', hence it is not full UTF-8.
To use 262014495440896000 as a field name, convert it to string first.
Thank you
I just want to thank you for clicking on this question! I've tried my best to make this as thorough as possible.
but still, feel free to let me know if you need to clarify anything further!
if you think the question is too long. you can just read the third & fourth part and post your own solution down here!
Setup
Mongodb Java driver: org.mongodb:mongo-java-driver:3.11.0-rc0
What I want to do
find a specific document with a specific "name" field.
then update the other field or the whole document.
Example Document
// the document that I am trying to find in db
{
"_id":"5de6af7cfa42833bd9849477",
"name":"Richard Koba",
"skills":[]
}
// the document that I have
{
"name":"Richard Koba",
"skills":[jump, dance, sing]
}
// final result in db
{
"_id":"5de6af7cfa42833bd9849477",
"name":"Richard Koba",
"skills":[jump, dance, sing]
}
What I am doing now
// finding a document with same "name" field as input doc and update it with doc
public MongoCollection updateDocument(Document doc, String colName) {
MongoCollection collection;
// make sure collection exist
try {
collection = connectCollection(colName); // returns MongoCollection Obj
} catch (CollectionNotFoundException e) {
MessageHandler.errorMessage(e.getMessage());
return null;
}
// trying to find the document.
if (collection.find(eq("name", doc.get("name"))).first() == null) {
// if document not found, insert a new one
collection.insertOne(doc);
} else {
// if the document found, replace/update it with the one I have
collection.replaceOne(eq("name", doc.get("name")), doc);
}
return collection;
}
What I found about my false solution
collection.find(eq("name", doc.get("name"))).first() never returns null.
Java only tells me it returns an Object. MongoDB Documentation tells me it is a TResult, which point back to MongoIterable<TResult>. I am stuck here.
the code outcome is that none of the documents is inserted/updated in the end.
Reference
https://mongodb.github.io/mongo-java-driver/3.11/javadoc/com/mongodb/client/MongoIterable.html#first()
I tried some code and this works fine. This is not much different from your code.
Created a document from mongo shell:
MongoDB Enterprise > db.users.findOne()
{
"_id" : "5de6af7cfa42833bd9849477",
"name" : "Richard Koba",
"skills" : [ ]
}
My Java Code:
// Test input documents
private Document doc1 = new Document()
.append("name", "Richard Koba")
.append("skills", Arrays.asList("jump", "dance", "sing"));
private Document doc2 = new Document()
.append("name", "Richard K")
.append("skills", Arrays.asList("sings"));
When doc1 is passed to the following method the result is: "### Doc FOUND". And, with doc2 the result is "### Doc NOT found".
private void checkDocument(Document doc) {
MongoClient mongoClient = MongoClients.create("mongodb://localhost/");
MongoDatabase database = mongoClient.getDatabase("javadb");
MongoCollection<Document> collection = database.getCollection("users");
if (collection.find(eq("name", doc.get("name"))).first() == null) {
System.out.println("### Doc NOT found");
}
else {
System.out.println("### Doc FOUND");
}
}
I also tried this, with the same results.
Document d = collection.find(eq("name", doc.get("name"))).first();
if (d == null) { // ... }
I also tried this; works fine too.
if (collection.find(queryFilter).iterator().tryNext() == null) { // ... }
I think there might be some other issue with your code or the database / collection. Some debugging and testing with new data might reveal the real issue.
Did you check if the document already exists in the collection, from mongo shell or Compass tools?
Are you using the right database and collection names?
After each test run are you verifying the data in the database if it is updated / inserted?
collection.find(eq("name", doc.get("name"))).first() never returns
null.
With the code I posted above, the find query did return null when the users collection was empty.
collection.find() return an array of documents. What you actually want here is collection.findOneAndUpdate()
After you get a TDoucment object from findOneAndUpdate, you can use a ObjectMapper e.g.jackson to map it back to a java object
I need to get single the GridFS file using Java driver 3.7+.
I have two collections with file in a database: photo.files and photo.chunks.
The photo.chunks collection contains the binary file like:
The photo.files collection contains the metadata of the document.
To find document using simple database I wrote:
Document doc = collection_messages.find(eq("flag", true)).first();
String messageText = (String) Objects.requireNonNull(doc).get("message");
I tried to find file and wrote in same way as with an example above, according to my collections on screens:
MongoDatabase database_photos = mongoClient.getDatabase("database_photos");
GridFSBucket photos_fs = GridFSBuckets.create(database_photos,
"photos");
...
...
GridFSFindIterable gridFSFile = photos_fs.find(eq("_id", new ObjectId()));
String file = Objects.requireNonNull(gridFSFile.first()).getMD5();
And like:
GridFSFindIterable gridFSFile = photos_fs.find(eq("_id", new ObjectId()));
String file = Objects.requireNonNull(gridFSFile.first()).getFilename();
But I get an error:
java.lang.NullPointerException
at java.util.Objects.requireNonNull(Objects.java:203)
at project.Bot.onUpdateReceived(Bot.java:832)
at java.util.ArrayList.forEach(ArrayList.java:1249)
Also I checked docs of 3.7 driver, but this example shows how to find several files, but I need single:
gridFSBucket.find().forEach(
new Block<GridFSFile>() {
public void apply(final GridFSFile gridFSFile) {
System.out.println(gridFSFile.getFilename());
}
});
Can someone show me an example how to realize it properly?
I mean getting data, e.g. in chunks collection by Object_id and md5 field also by Object_id in metadata collection.
Thanks in advance.
To find and use specific files:
photos_fs.find(eq("_id", objectId)).forEach(
(Block<GridFSFile>) gridFSFile -> {
// to do something
});
or as alternative, I can find specific field of the file.
It can be done firstly by creating objectId of the first file, then pass it to GridFSFindIterable object to get particular field and value from database and get finally file to convert into String.
MongoDatabase database_photos =
mongoClient.getDatabase("database_photos");
GridFSBucket photos_fs = GridFSBuckets.create(database_photos,
"photos");
...
...
ObjectId objectId = Objects.requireNonNull(photos_fs.find().first()).getObjectId();
GridFSFindIterable gridFSFindIterable = photos_fs.find(eq("_id", objectId));
GridFSFile gridFSFile = Objects.requireNonNull(gridFSFindIterable.first());
String file = Objects.requireNonNull(gridFSFile).getMD5();
But it checks files from photo.files not from photo.chunkscollection.
And I'm not sure that this way is code-safe, because of debug info, but it works despite the warning:
Inconvertible types; cannot cast 'com.mongodb.client.gridfs.model.GridFSFile' to 'com.mongodb.client.gridfs.GridFSFindIterableImpl'
currently I'm trying to learn dealing with MongoDB in Java. I created the collection "plots" and inserted a document:
final Document plotObj = new Document();
plotObj.put(DataKey.PLOT_UUID.getKey(), plot.getUniqueId());
plotObj.put(DataKey.REGION_ID.getKey(), plot.getRegionId());
plotObj.put(DataKey.REGION_WORLD.getKey(), plot.getRegionWorld());
plotObj.put(DataKey.REGION_OWNER.getKey(), plot.getPlotOwner().isPresent() ? plot.getPlotOwner() : null);
plotObj.put(DataKey.PLOT_TRUSTED.getKey(), new BasicDBList().addAll(plot.getTrusted()));
this.collection.insertOne(plotObj);
"DataKey.PLOT_UUID.getKey()" represents a String. "plot.getUniqueId()" represents a java.util.UUID. After inserting this Document, I want to query it:
public boolean hasPlot(UUID plotId){
final BasicDBObject query = new BasicDBObject(DataKey.PLOT_UUID.getKey(), new BasicDBObject("$eq", plotId));
return this.collection.find(query).iterator().hasNext();
}
However this methods always returns false event though the Document was successfully inserted.
Maybe this problem can be fixed with ease but nevertheless: thanks in advance! :)
According to the documentation you don't need the $eq
just write
new BasicDBObject(DataKey.PLOT_UUID.getKey(), plotId));
Here is a simple pojo:
public class Description {
private String code;
private String name;
private String norwegian;
private String english;
}
And please see the following code to apply an upsert to MongoDb via spring MongoTemplate:
Query query = new Query(Criteria.where("code").is(description.getCode()));
Update update = new Update().set("name", description.getName()).set("norwegian", description.getNorwegian()).set("english", description.getEnglish());
mongoTemplate.upsert(query, update, "descriptions");
The line to generate the Update object specifies every field of the Item class manually.
But if my Item object changes then my Dao layer breaks.
So is there a way to avoid doing this, so that all fields from my Item class are applied automatically to the update?
E.g.
Update update = new Update().fromObject(item);
Note that my pojo does not extend DBObject.
I found a pretty good solution for this question
//make a new description here
Description d = new Description();
d.setCode("no");
d.setName("norwegian");
d.setNorwegian("norwegian");
d.setEnglish("english");
//build query
Query query = new Query(Criteria.where("code").is(description.getCode()));
//build update
DBObject dbDoc = new BasicDBObject();
mongoTemplate.getConverter().write(d, dbDoc); //it is the one spring use for convertions.
Update update = Update.fromDBObject(dbDoc);
//run it!
mongoTemplate.upsert(query, update, "descriptions");
Plz note that Update.fromDBObject return an update object with all fields in dbDoc. If you just want to update non-null fields, you should code a new method to exclude null fields.
For example, the front-end post a doc like below:
//make a new description here
Description d = new Description();
d.setCode("no");
d.setEnglish("norwegian");
We only need to update the field 'language':
//return Update object
public static Update fromDBObjectExcludeNullFields(DBObject object) {
Update update = new Update();
for (String key : object.keySet()) {
Object value = object.get(key);
if(value!=null){
update.set(key, value);
}
}
return update;
}
//build udpate
Update update = fromDBObjectExcludeNullFields(dbDoc);
The solution for a new spring-data-mongodb version 2.X.X.
The API has evolved, since 2.X.X version there is:
Update.fromDocument(org.bson.Document object, String... exclude)
instead of (1.X.X):
Update.fromDBObject(com.mongodb.DBObject object, String... exclude)
The full solution:
//make a new description here
Description d = new Description();
d.setCode("no");
d.setName("norwegian");
d.setNorwegian("norwegian");
d.setEnglish("english");
Query query = new Query(Criteria.where("code").is(description.getCode()));
Document doc = new Document(); // org.bson.Document
mongoTemplate.getConverter().write(item, doc);
Update update = Update.fromDocument(doc);
mongoTemplate.upsert(query, update, "descriptions");
It works!
you can use save : (if non exist = insert else = upsert)
save(Object objectToSave, String collectionName)
read : javadoc
Just like previous answers said, use mongoTemplate.getConverter().write() and Update.fromDocument() functions. But i found Update.fromDocument() won't add "$set" key and won't work directly, the solution is to add "$set" yourself, like below (PS: I'm using 2.2.1.RELEASE version):
public static Update updateFromObject(Object object, MongoTemplate mongoTemplate) {
Document doc = new Document();
mongoTemplate.getConverter().write(object, doc);
return Update.fromDocument(new Document("$set", doc));
}
If you want to upsert Pojos incl. property String id; you have to exclude the _id field in the fromDBObject method Update.fromDBObject(dbDoc,"_id").
Otherwise you get the Exception:
org.springframework.dao.DuplicateKeyException: { "serverUsed" : "127.0.0.1:27017" , "ok" : 1 , "n" : 0 , "updatedExisting" : false , "err" : "E11000 duplicate key error collection: db.description index: _id_ dup key: { : null }" , "code" : 11000}; nested exception is com.mongodb.MongoException$DuplicateKey: { "serverUsed" : "127.0.0.1:27017" , "ok" : 1 , "n" : 0 , "updatedExisting" : false , "err" : "E11000 duplicate key error collection: db.description index: _id_ dup key: { : null }" , "code" : 11000}
because the _id field of the first is null
{
"_id" : null,
...
}
Fullcode based on #PaniniGelato answer would be
public class Description(){
public String id;
...
}
Description d = new Description();
d.setCode("no");
d.setName("norwegian");
d.setNorwegian("norwegian");
d.setEnglish("english");
//build query
Query query = new Query(Criteria.where("code").is(description.getCode()));
//build update
DBObject dbDoc = new BasicDBObject();
mongoTemplate.getConverter().write(d, dbDoc); //it is the one spring use for convertions.
Update update = Update.fromDBObject(dbDoc, "_id");
//run it!
mongoTemplate.upsert(query, update, "descriptions");
Then the upsert is working in the cases of insert and update. Corrections & thoughts are welcome ;)
This is what I am doing for the time being. Not so much elegant way to do it, but it does save a precious DB call:
import org.springframework.data.mongodb.core.MongoTemplate;
import org.springframework.data.mongodb.core.query.Query;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.mongodb.BasicDBObject;
import com.mongodb.DB;
import com.mongodb.DBCollection;
import com.mongodb.DBObject;
import com.mongodb.util.JSON;
/**
* Perform an upsert operation to update ALL FIELDS in an object using native mongo driver's methods
* since mongoTemplate's upsert method doesn't allow it
* #param upsertQuery
* #param object
* #param collectionName
*/
private void performUpsert(Query upsertQuery, Object object, String collectionName){
ObjectMapper mapper = new ObjectMapper();
try {
String jsonStr = mapper.writeValueAsString(object);
DB db = mongoTemplate.getDb();
DBCollection collection = db.getCollection(collectionName);
DBObject query = upsertQuery.getQueryObject();
DBObject update = new BasicDBObject("$set", JSON.parse(jsonStr));
collection.update(query, update, true, false);
} catch (IOException e) {
LOGGER.error("Unable to persist the metrics in DB. Error while parsing object: {}", e);
}
}
There are two cases here that need to be distinguished:
Update an item that was previously fetched from the DB.
Update or insert (upsert) an item you created by code.
In Case 1) You can simply use mongoTemplate.save(pojo, "collection"), because your POJO will already have a filled ObjectID in its id field.
In case 2) You have to explain to mongo what "already exists" means in case of your domain model: By default the mongoTemplate.save() method updates an existing item, if there is one with that same ObjectId. But with a newly instantiated POJO you do not have that id. Therefore the mongoTemplate.upsert() method has a query parameter that you can create like this:
MyDomainClass pojo = new MyDomainClass(...);
Query query = Query.query(Criteria.where("email").is("user1#domain.com"));
DBObject dbDoc = new BasicDBObject();
mongoTemplate.getConverter().write(pojo, dbDoc); //it is the one spring use for convertions.
dbDoc.removeField("_id"); // just to be sure to not create any duplicates
Update update = Update.fromDBObject(dbDoc);
WriteResult writeResult = mongoTemplate.upsert(query, update, UserModel.class);
I ran into the same problem. In het current Spring Data MongoDB version no such thing is available. You have to update the seperate fields by hand.
However it is possible with another framework: Morphia.
This framework has a wrapper for DAO functionality: https://github.com/mongodb/morphia/wiki/DAOSupport
You can use the DAO API to do things like this:
SomePojo pojo = daoInstance.findOne("some-field", "some-value");
pojo.setAProperty("changing this property");
daoInstance.save(pojo);
I think that:
Description add a property
#Id
private String id;
then get a document by the query condition,set Description's id by document's id.
and save
Just use ReflectionDBObject - if you make Description extend it, you should just get your object's fields transferred to Update reflectively, automagically. The note from above about null fields included in the update still holds true.
public void saveOrUpdate(String json) {
try {
JSONObject jsonObject = new JSONObject(json);
DBObject update1 = new BasicDBObject("$set", JSON.parse(json));
mongoTemplate.getCollection("collectionName").update(new Query(Criteria.where("name").is(jsonObject.getString("name"))).getQueryObject(), update1, true, false);
} catch (Exception e) {
throw new GenericServiceException("Error while save/udpate. Error msg: " + e.getMessage(), e);
}
}
this is very simple way to save json string into collection using mongodb
and spring.
This method can be override to use as JSONObject.
#Override
public void updateInfo(UpdateObject algorithm) {
Document document = new Document();
mongoTemplate.getConverter().write(algorithm, document);
Update update = Update.fromDocument(document);
mongoTemplate.updateFirst(query(where("_id").is(algorithm.get_id())), update, UpdateObject.class);
}
After upsert, I was Tring to fetch same record but it was given me the old one.
But in dB I am having new records.