Sheel :
I have found several example at StackOverFlow related to addFields in Aggregation. But no one implemented in Java.
db.getCollection('myDocument').aggregate([
{$match : {"metaId.ref.uuid" : "d6112808-1ce1-4545-bd52-cf55bc4ed25e"}},
{$lookup: {from: "simple", localField: "someId.ref.uuid", foreignField: "uuid",
as: "simple"}},
{"$unwind": "$simple"},
{"$addFields": { "metaId.ref.name" : "$simple.name" }}
])
I am not able to Implement In Java Correctly:-- Not getting proper procedure
LookupOperation lookupOperation =LookupOperation.newLookup().from("simple").localField("execId.ref.uuid").foreignField("uuid").as("simple");
Aggregation myDocAggr = newAggregation(match(Criteria.where("metaId.ref.uuid").is(someUUID)), group("uuid").max("version").as("version"),
lookupOperation,
Aggregates.unwind(""),
Aggregates.addFields(fields));
Document document =new Document();
AggregationResults<String> myDocAggrResults = mongoTemplate.aggregate(myDocAggr , myDocument, myDocument.class);
List<String> mydocumentList = myDocAggrResults .getMappedResults();
Not able to use unwind and addFields, this is sample java code, but it is not ok. Please help me. Thanks in advance
user2683814 :
You are mixing the java driver Aggregates
method with Spring Aggregation
methods.
Also $addFields
is still not supported
in spring mongo.
You have to use below aggregation.
import static org.springframework.data.mongodb.core.aggregation.Aggregation.*;
Aggregation myDocAggr = newAggregation(
match(Criteria.where("metaId.ref.uuid").is(someUUID)),
group("uuid").max("version").as("version"),
lookup("simple","execId.ref.uuid","uuid","simple"),
unwind("simple"),
new AggregationOperation(){
@Override
public Document toDocument(AggregationOperationContext aoc) {
return new Document("$addFields",new Document("metaId.ref.name","$simple.name"));
}
}
)
List<Document> mydocumentList=mongoTemplate.aggregate(myDocAggr,"myDocument",Document.class).getMappedResults();