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Spring data aggregation query elasticsearch

I am trying to make the below elasticsearch query to work with spring data. The intent is to return unique results for the field "serviceName". Just like a SELECT DISTINCT serviceName FROM table would do comparing to a SQL database.
{
"aggregations": {
"serviceNames": {
"terms": {
"field": "serviceName"
}
}
},
"size":0
}
I configured the field as a keyword and it made the query work perfectly in the index_name/_search api as per the response snippet below:
"aggregations": {
"serviceNames": {
"doc_count_error_upper_bound": 0,
"sum_other_doc_count": 0,
"buckets": [
{
"key": "service1",
"doc_count": 20
},
{
"key": "service2",
"doc_count": 8
},
{
"key": "service3",
"doc_count": 8
}
]
}
}
My problem is the same query doesn't work in Spring data when I try to run with a StringQuery I get the error below. I am guessing it uses a different api to run queries.
Cannot execute jest action , response code : 400 , error : {"root_cause":[{"type":"parsing_exception","reason":"no [query] registered for [aggregations]","line":2,"col":19}],"type":"parsing_exception","reason":"no [query] registered for [aggregations]","line":2,"col":19} , message : null
I have tried using the SearchQuery type to achieve the same results, no duplicates and no object loading, but I had no luck. The below sinnipet shows how I tried doing it.
final TermsAggregationBuilder aggregation = AggregationBuilders
.terms("serviceName")
.field("serviceName")
.size(1);
SearchQuery searchQuery = new NativeSearchQueryBuilder()
.withIndices("index_name")
.withQuery(matchAllQuery())
.addAggregation(aggregation)
.withSearchType(SearchType.DFS_QUERY_THEN_FETCH)
.withSourceFilter(new FetchSourceFilter(new String[] {"serviceName"}, new String[] {""}))
.withPageable(PageRequest.of(0, 10000))
.build();
Would someone know how to achieve no object loading and object property distinct aggregation on spring data?
I tried many things without success to print queries on spring data, but I could not, maybe because I am using the com.github.vanroy.springdata.jest.JestElasticsearchTemplate implementation.
I got the query parts with the below:
logger.info("query:" + searchQuery.getQuery());
logger.info("agregations:" + searchQuery.getAggregations());
logger.info("filter:" + searchQuery.getFilter());
logger.info("search type:" + searchQuery.getSearchType());
It prints:
query:{"match_all":{"boost":1.0}}
agregations:[{"serviceName":{"terms":{"field":"serviceName","size":1,"min_doc_count":1,"shard_min_doc_count":0,"show_term_doc_count_error":false,"order":[{"_count":"desc"},{"_key":"asc"}]}}}]
filter:null
search type:DFS_QUERY_THEN_FETCH

I figured out, maybe can help someone. The aggregation don't come with the query results, but in a result for it self and is not mapped to any object. The Objects results that comes apparently are samples of the query elasticsearch did to run your aggregation (not sure, maybe).
I ended up by creating a method which can do a simulation of what would be on the SQL SELECT DISTINCT your_column FROM your_table, but I think this will work only on keyword fields, they have a limitation of 256 characters if I am not wrong. I explained some lines in comments.
Thanks #Val since I was only able to figure it out when debugged into Jest code and check the generated request and raw response.
public List<String> getDistinctField(String fieldName) {
List<String> result = new ArrayList<>();
try {
final String distinctAggregationName = "distinct_field"; //name the aggregation
final TermsAggregationBuilder aggregation = AggregationBuilders
.terms(distinctAggregationName)
.field(fieldName)
.size(10000);//limits the number of aggregation list, mine can be huge, adjust yours
SearchQuery searchQuery = new NativeSearchQueryBuilder()
.withIndices("your_index")//maybe can be omitted
.addAggregation(aggregation)
.withSourceFilter(new FetchSourceFilter(new String[] { fieldName }, new String[] { "" }))//filter it to retrieve only the field we ar interested, probably we can take this out.
.withPageable(PageRequest.of(0, 1))//can't be zero, and I don't want to load 10 results every time it runs, will always return one object since I found no "size":0 in query builder
.build();
//had to use the JestResultsExtractor because com.github.vanroy.springdata.jest.JestElasticsearchTemplate don't have an implementation for ResultsExtractor, if you use Spring defaults, you can probably use it.
final JestResultsExtractor<SearchResult> extractor = new JestResultsExtractor<SearchResult>() {
#Override
public SearchResult extract(SearchResult searchResult) {
return searchResult;
}
};
final SearchResult searchResult = ((JestElasticsearchTemplate) elasticsearchOperations).query(searchQuery,
extractor);
final MetricAggregation aggregations = searchResult.getAggregations();
final TermsAggregation termsAggregation = aggregations.getTermsAggregation(distinctAggregationName);//this is where your aggregation results are, in "buckets".
result = termsAggregation.getBuckets().parallelStream().map(TermsAggregation.Entry::getKey)
.collect(Collectors.toList());
} catch (Exception e) {
// threat your error here.
e.printStackTrace();
}
return result;
}

How to upsert nested value using Spring-Data for Mongodb

I am trying to update the following JSON doc in mongodb so that a new document will be created if there is not one matching the "altKey", but if there is a document matching the altKey, any matching "records" will have their "domain" set and their "counts" incremented. I have a requirement that the JSON structure not change and that Spring-Data for mongodb is used.
{
"altKey": "value"
"records": {
"randomName1" {
"domain": "domainValue",
"count": 3
},
"randomName2" {
"domain": "domainValue2",
"count": 5
},
...
"randomNameN" {
"domain": "domainValueN",
"count": 4
}
}
}
The relevent portion of the class I have been attempting to do the update with is:
#Autowired
private MongoTemplate mongoTemplate;
#Override
public void increment(Doc doc) {
Query query = new Query().addCriteria(Criteria.where("altKey").is(doc.getAltKey());
Update update = new Update();
update.setOnInsert("altKey", doc.getAltKey());
for (final Map.Entry<String, RecordData> entry :
doc.getRecords().entrySet()) {
String domainKey = format("records.{0}.domain", entry.getKey());
String domainValue = entry.getValue().getDomain();
update.set(domainKey, domainValue);
String countKey = format("records.{0}.count", entry.getKey());
Integer countValue = entry.getValue().getCount();
update.inc(countKey, countValue);
}
mongoTemplate.upsert(query, update, Doc.class);
}
When I attempt to call the increment method the "altKey" field is successfully persisted, but none of the records persist and I am not sure of why that is. I believe the reason is my attempt to use mongo dot operation for the key when doing the set and inc update portions (ie "records.randomNameN.domain" or "records.randomNameN.count") but I haven't been able to find an alternate way to configure the Update object when I don't know until run time what the name of a particular record will be.
Anyone out there know how to set up the Update object to handle setting nested fields?

Aggregation query with lookup in Spring

I'm using the Spring framework to perform an aggregation on my mongodb. However, the lookup keeps failing and I can't understand why. Here's the query:
Aggregation aggregation = newAggregation(
match(Criteria.where("idOfUser").is(loggedInAccount.getId())),
group("imgID"),
new CustomAggregationOperation(
new BasicDBObject("$lookup",
new BasicDBObject("from","img")
.append("localField","_id")
.append("foreignField","_id")
.append("as","uniqueImgs")
)
),
limit(pageable.getPageSize()),
skip(pageable.getPageSize()*pageable.getPageNumber())
);
AggregationResults aggregationResults = mongo.aggregate(aggregation, "comment", String.class); //Using String at the moment just to see the output clearly.
CustomAggregationOperation is as follows:
public class CustomAggregationOperation implements AggregationOperation {
private DBObject operation;
public CustomAggregationOperation (DBObject operation) {
this.operation = operation;
}
#Override
public DBObject toDBObject(AggregationOperationContext context) {
return context.getMappedObject(operation);
}
}
The Spring MongoDB version of lookup isn't recognised which is why I'm using this CustomAggregationOperation. AFAIK it shouldn't affect it.
Ideally what I want to happen is:
Get all the comments of the user.
Make sure that the imgID is distinct for the comments (so there are only the id's of the imgs that have been commented on)
Get the actual img objects related to these ids.
Paginate the returned imgs.
At the moment, step 3 doesn't work, and I think 4 wouldn't work either since limit and skip won't be applied to the objects in "uniqueImgs".
What is returned is:
[{ "_id" : "570e2f5cb1b9125510a443f5" , "uniqueImgs" : [ ]}]
How can I fix this?
EDIT
the imgID stored isn't an ObjectID whereas the _id in the img collection is. Would that have any effect?

The current release (at the time of writing 1.9.5) has support for the $lookup operator and can be implemented as (untested):
LookupOperation lookupOperation = LookupOperation.newLookup()
.from("img")
.localField("_id")
.foreignField("_id")
.as("uniqueImgs");
Aggregation agg = newAggregation(
match(Criteria.where("idOfUser").is(loggedInAccount.getId())),
group("imgID"),
lookupOperation,
limit(pageable.getPageSize()),
skip(pageable.getPageSize()*pageable.getPageNumber())
);
AggregationResults aggregationResults = mongo.aggregate(agg, "comment", String.clas);

How to custom search for text query in mongodb?

I'm new in mongodb. I have following data as a JSON format in mongodb. I need to search the bookLabel or the shortLabel for the book and it should show me all the information about the book. For example: if I query for 'Cosmos' it'll show all the description about the book, like: bookLabel, writer, yearPublish, url. How can I do that in java? Need query, please help.
"Class":"Science",
"Description":[
{
"bookLabel":"Cosmos (Mass Market Paperback)",
"shortLabel":"Cosmos",
"writer":"Carl Sagan",
"yearPublish":[
"2002"
],
"url":"https://www.goodreads.com/book/show/55030.Cosmos"
},
{
"bookLabel":"The Immortal Life of Henrietta Lacks",
"shortLabel":"Immortal Life",
"writer":"Rebecca Skloot",
"yearPublish":[
"2010, 2011"
],
"url":"https://www.goodreads.com/book/show/6493208-the-immortal-life-of-henrietta-lacks"
}
],
"Class":"History",
"Description":[
{
"bookLabel":"The Rise and Fall of the Third Reich",
"shortLabel":"Rise and Fall",
"writer":"William L. Shirer",
"yearPublish":[
"1960"
],
"url":"https://www"
}
]
}

With MongoDB Java Driver v3.2.2 you can do something like this:
FindIterable<Document> iterable = collection.find(Document.parse("{\"Description.shortLabel\": {$regex: \"Cosmos\"}"));
This returns all documents containing Cosmos in the Description.shortLabel nested field. For an exact match, try this {"Description.shortLabel": "Cosmos"}. Replace shortLabel with bookLabelto search the bookLabel field. Then you can do iterable.forEach(new Block<Document>()) on the returned documents. To search both bookLabel and shortLabel, you can do a $or{}. My syntax could be wrong so check the MongoDB manual. But this is the general idea.

For this, you can use MongoDB's Text Search Capabilities. You'll have to create a text index on your collection for that.
First of all create a text index on your collection on fields bookLabel and shortLabel.
db.books.createIndex({ "Description.bookLabel" : "text", "Description.shortLabel" : "text" })
Note that this is done in the Mongo shell
Then
DBObject command = BasicDBObjectBuilder
.start("text", "books")
.append("search", "Cosmos")
.get();
CommandResult result = db.command(command);
BasicDBList results = (BasicDBList) result.get("results");
for(Object o : results) {
DBObject dbo = (DBObject) ((DBObject) o).get("obj");
String id = (String) dbo.get("_ID");
System.out.println(id);
}
Haven't really tested this. But just give it a try. Should work.

Spring data mongodb removes a positional operator from "$unset" update query part

I have a collection of users:
> db.users.find().pretty()
{
"_id" : ObjectId("544ab933e4b099c3cfb62e12"),
"token" : "8c9f8cf4-1689-48ab-bf53-ee071a377f60",
"categories" : [
DBRef("cue_categories", ObjectId("544ab933e4b099c3cfb62e10")),
DBRef("cue_categories", ObjectId("544ab933e4b099c3cfb62e11"))
]
}
I want to find all users who have (let's say) ObjectId("544ab933e4b099c3cfb62e10") category and remove it (because this category was deleted and I don't want users to refer to it anymore).
The valid query to do it in JSON format would be:
db.users.update({
categories:{
$in:[
DBRef("cue_categories", ObjectId("544ab933e4b099c3cfb62e10"))
]
}
},
{
$unset:{
"categories.$":true
}
})
Here's a Spring mongodb query:
Query query = new Query();
query.addCriteria(Criteria.where("categories.$id").in(categoryIds));
Update update = new Update();
update.unset("categories.$");
operations.updateMulti(query, update, User.class);
In order to make an appropriate DB reference I have to provide a list of category IDs, each category ID (in categoryIds) is an instance of org.bson.types.ObjectId.
The problem is that the result query turns out to be without a positional operator:
DEBUG o.s.data.mongodb.core.MongoTemplate - Calling update using
query: { "categories.$id" : { "$in" : [ { "$oid" :
"544ab933e4b099c3cfb62e10"}]}} and update: { "$unset" : { "categories"
: 1}} in collection: users
So the update part must be { "$unset" : { "categories.$" : 1}}
P.S.
I managed to get around by falling back to the plain Java driver use
DBObject query = new BasicDBObject("categories.$id", new BasicDBObject("$in", categoryIds));
DBObject update = new BasicDBObject("$unset", new BasicDBObject("categories.$", true));
operations.getCollection("users").updateMulti(query, update);
But my question still remains open!
P.S.S.
My case is very similar to Update Array Field Using Positional Operator ($) Does Not Work bug and looks like it was fixed for versions 1.4.1 and 1.5. That being said I use spring-data-mongodb version 1.5.1. And I'm confused. Does anybody have a clue?

You can not use positional $ operator with unset as per MongoDB documentation. It will set the value as Null. https://docs.mongodb.com/manual/reference/operator/update/positional/