I'm wondering how can I list Grails domain and exclude some fields at same time. I'm guessing solution must be simple but I just can not see it.
I prepared some example with domain User:
class User implements Serializable {
String username
String email
Date lastUpdated
String password
Integer status
static constraints = { }
static mapping = { }
}
At this point I want to list all users which have status below 2.
render User.findAllByStatusLessThen(2) as JSON
I want to render JSON response to clientside without some fields. For example I just want to render users with fields username and lastUpdated so rendered JSON would look like this:
[{"username": "user1", "lastUpdated":"2016-09-21 06:49:46"}, {"username": "user2", "lastUpdated":"2016-09-22 11:24:42"}]
What's the easiest way to achieve that?
Yeah.It's simple.Try below solutions
Solution 1
List userList = User.where{ status < 2 }.property("username").property("lastUpdated").list()
render userList as JSON
output
[{"user1", "2016-09-21 06:49:46"}, {"user2", "2016-09-22 11:24:42"}]
Solution 2 - using this you will get output in the Key-Value pair
List userList = User.findAllByStatusLessThen(2)?.collect{
[username : it.username, lastUpdated: it.lastUpdated]}
render userList as JSON
output
[{"username": "user1", "lastUpdated":"2016-09-21 06:49:46"}, {"username": "user2", "lastUpdated":"2016-09-22 11:24:42"}]
You are looking for Grails projections.
def result = Person.createCriteria().list {
lt("status", 2)
projections {
property('username')
property('lastUpdated')
}
} as JSON
Well if you want the result to be in key-value pair you can take advantage of HQL query
def query = """select new map(u.username as username, u.lastUpdated as lastUpdated) from User u where status < 2"""
def result = User.executeQuery(query)
println (result as JSON)
This will give you the output as below
[{"username": "user1", "lastUpdated":"2016-09-21 06:49:46"}, {"username": "user2", "lastUpdated":"2016-09-22 11:24:42"}]
Related
I wrote an app that has a logic for email verification and it's trigered when an user sign up. I use two Mongoose models: one to record the data from the users and other model for the authentication tokens. In the token schema I grab the user's ID.
In my User controller, when the app needs to authenticate the token that was prevously sent to the user, the token is identified and after that I must to find the user's ID that was recorded in the token schema in it's Mongo collection. For that, I have a User.findOne() function.
What I'm wanna do is to grab the _userId:ObjectId("some-userid-number") that is stored in the token collection, but I must to doi te inside the fuction, something like that
User.findOne({ _userID: mongoose.Schema.Types.ObjectId._userID, ref: 'Token' })
So, how can I grab the _userId stored as a ObjectId in the Token model?
Thanks a lot!
If the Mongoose models are defined with refs, findOne/findAll can join data from multiple collections using populate. Note that using populate will result in multiple queries being sent to mongodb.
Token
.findOne({ token })
.select("_userId")
.populate({
path: '_userId',
select: 'firstName', // Specify the necessary user properties
options: { lean: true }
})
.lean()
.exec();
The request can instead be formulated as an aggregation query if performance is important. This request will result in a single query being sent to mongodb.
Token
.aggregate([
{$match: {
token
}},
{$lookup: {
from: 'users', // the name of the user collection
localField: '_userId',
foreignField: '_id',
as: 'user'
}},
{$project: {
// Specify the necessary user properties in the projection
firstName: '$user.firstName'
}}
])
.exec()
Remember to create an index on Token(_userId)
The answer is simple than I imagine :-)
async confirmationPost (req, res) {
const token_ = req.body.token;
await Token.findOne({ token:token_ }, function (err, tokenData) {
if (!tokenData) {
return res.status(),
}
else
{
tokenUser = tokenData._userId
User.findOne({ _id: tokenUser }, function (err, user) {
// logic-logic
}
I was able to captura all the token colletion data, so was a simpla case of defining tha variable :-)
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;
}
I'm using firebase4j (a firebase library for Java, I know it is much better to go with node, I just wanted to try to do it with Java). In my database I need to persist the url of images with a bunch of the picture's information. The thing is that the picture url itself is very deep into the JSON
"users" : {
"aCategory" : {
"aUser" : {
"photos" : {
"photoUid1" : [ {
"value1" : false,
"value2" : "qwerty",
"score" : 40,
"url" : "http://someurl.com"
}
That is why I am trying to create an index for the pictures ordered by score, containing the url pointing to the location of the photo object in the firebase database. Here is where the issue begins. Firebase4j does not let you push, to a list for example, so the index ends up with this format:
{
"-UID1": {
"firebaseImgUrl": "users/aCategory/aUser/photos/photoUid1",
"score": 31
},
"-UID2": {
"firebaseImgUrl": "users/aCategory/aUser/photos/photoUid2",
"score": 30
}
}
I already added the rule ".indexOn" in order for firebase to answer with the right photos when asked for http://firebaseurl.com/users/...?orderBy="score"&limitToFirst=10, which is what I'm doing. I would like to know how should I iterate a JSON object of object as shown in the example above. I'm receiving the data from an Angular 4 client. I've tried a number of methods which haven't worked for me:
result: Photo[] = [];
for(let key in json){
console.log(key); //prints the UIDs
console.log(key.url); //url is not a property of string
//thus
result.push(new Photo(key.url, key.score)); //not working
}
The key is only a string, indicating the keys in your json. You should use it to access your object, like this:
result: Photo[] = [];
for(let key in json){
result.push(new Photo(json[key].firebaseImgUrl, json[key].score));
}
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.
I have a template foo.mustache saved in {{ES_HOME}}/config/scripts.
POST to http://localhost:9200/forward/_search/template with the following message body returns a valid response:
{
"template": {
"file": "foo"
},
"params": {
"q": "a",
"hasfilters": false
}
}
I want to translate this to using the java API now that I've validated all the different components work. The documentation here describes how to do it in java:
SearchResponse sr = client.prepareSearch("forward")
.setTemplateName("foo")
.setTemplateType(ScriptService.ScriptType.FILE)
.setTemplateParams(template_params)
.get();
However, I would instead like to just send a plain string query (i.e. the contents of the message body from above) rather than build up the response using the java. Is there a way to do this? I know with normal queries, I can construct it like so:
SearchRequestBuilder response = client.prepareSearch("forward")
.setQuery("""JSON_QUERY_HERE""")
I believe the setQuery() method wraps the contents into a query object, which is not what I want for my template query. If this is not possible, I will just have to go with the documented way and convert my json params to Map<String, Object>
I ended up just translating my template_params to a Map<String, Object> as the documentation requires. I utilized groovy's JsonSlurper to convert the text to an object with a pretty simple method.
import groovy.json.JsonSlurper
public static Map<String,Object> convertJsonToTemplateParam(String s) {
Object result = new JsonSlurper().parseText(s);
//Manipulate your result if you need to do any additional work here.
//I.e. Programmatically determine value of hasfilters if filters != null
return (Map<String,Object>) result;
}
And you could pass in the following as a string to this method:
{
"q": "a",
"hasfilters": true
"filters":[
{
"filter_name" : "foo.untouched",
"filters" : [ "FOO", "BAR"]
},
{
"filter_name" : "hello.untouched",
"list" : [ "WORLD"]
}
]
}