$sort pipeline after $group not working using Spring aggregate class - spring

Question

I have a User collection which looks like below sample :
User :{
"_id" : ObjectId("59f6dc660a975a3e3290ea01"),
"basicInfo" : {
"name" : "xxxx",
"age" : 27,
"gender" : "Male"
}
"otherInfo" {
"projects" : [
{
"_id" : ObjectId("59f6f9230a975a67cc7d7638"),
"name" : "Test Project",
"projectImage" : "images/project/59f6f9230a975a67cc7d7638.jpg",
"desc" : "This is a testing project",
"status" : "Active",
"verifyDet" : {
"method" : "Admin",
"status" : "PENDING",
"isVerified" : false
}
},
{
"_id" : ObjectId("59f6f9230a975a67cc7d5556"),
"name" : "Test Project Two",
"projectImage" : "images/project/59f6f9230a975a67cc7d5556.jpg",
"desc" : "This is a testing project",
"status" : "Closed",
"verifyDet" : {
"method" : "Admin",
"status" : "APPROVED",
"isVerified" : true
}
}
]
}
}
Note: One user can be part of multiple projects. But he needs approval from Admin to participate in the project activities. Verification is managed by verifyDet and projects are managed by projects array.
Actual requirement is to show the list of members in such a way that members having verification pending comes on top in alphabetic order and then approved/verified members in alphabetic order to Admin.
When I run below query on mongo shell I get list of Users with only one project detail(_id=59f6f9230a975a67cc7d7638) for which I want to search and result sorted by Verification pending users and User name. The result comes appropriately.
db.User.aggregate(
{$unwind:"$otherInfo.projects"},
{
$match:{
"otherInfo.projects._id":ObjectId("59f6f9230a975a67cc7d7638"),
"otherInfo.projects.status":"Active"
}
},
{$group: {_id: {"_id":"$_id", "basicInfo":"$basicInfo"}, "projects": {$push: "$otherInfo.projects"}}},
{$project:{"_id":"$_id._id", "basicInfo":"$_id.basicInfo", "otherInfo.projects":"$projects"}},
{$sort:{"otherInfo.projects.verifyDet.isVerified":1, "basicInfo.name":1}}
)
But when I create same aggregate in Spring like mentioned below I get exception:
public List<Map> fetchUsersList(String projectId, Pageable pageable) {
//unwind operation
AggregationOperation unwindOp = Aggregation.unwind("$otherInfo.projects");
Criteria criteria = Criteria.where("otherInfo.projects._id").is(new ObjectId(projectId));
criteria.and("otherInfo.projects.status").is("Active");
AggregationOperation matchOp = Aggregation.match(criteria);
AggregationOperation groupOp = Aggregation.group(
Fields.from(Fields.field("_id", "$_id")).and(Fields.field("basicInfo","$basicInfo"))).push("$otherInfo.projects").as("projects");
AggregationOperation projectOp = Aggregation.project(
Fields.from(Fields.field("_id","$_id._id"),
Fields.field("basicInfo","$_id.basicInfo"),
Fields.field("otherInfo.projects","$projects")));
AggregationOperation sortOp = Aggregation.sort(Direction.DESC, "otherInfo.projects.verifyDet.isVerified").and(Direction.DESC, "basicInfo.name");
Aggregation agg = Aggregation.newAggregation(unwindOp, matchOp, groupOp, projectOp, sortOp);
AggregationResults<User> results = mongoTemplate.aggregate(agg,
"User", User.class);
return results.getMappedResults();
}
Exception :
2017-12-15 19:24:31,852 ERROR GlobalExceptionHandler:75 - Exception Stack Trace :
java.lang.IllegalArgumentException: Invalid reference 'otherInfo.projects.verifyDet.isVerified'!
at org.springframework.data.mongodb.core.aggregation.ExposedFieldsAggregationOperationContext.getReference(ExposedFieldsAggregationOperationContext.java:99)
at org.springframework.data.mongodb.core.aggregation.ExposedFieldsAggregationOperationContext.getReference(ExposedFieldsAggregationOperationContext.java:80)
at org.springframework.data.mongodb.core.aggregation.SortOperation.toDBObject(SortOperation.java:73)
at org.springframework.data.mongodb.core.aggregation.AggregationOperationRenderer.toDBObject(AggregationOperationRenderer.java:56)
at org.springframework.data.mongodb.core.aggregation.Aggregation.toDbObject(Aggregation.java:580)
at org.springframework.data.mongodb.core.aggregation.Aggregation.toString(Aggregation.java:596)
at com.grpbk.gp.repository.impl.UserRepositoryCustomImpl.fetchUsersList(UserRepositoryCustomImpl.java:1128)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
Please let me know what I am doing wrong.

Answer 1

"otherInfo.projects.verifyDet.isVerified" field needs to be present in Project Oepration or group operation so that sort would get a reference for that.