What is the best practice using ElasticSearch from Java?
For instance one can easily find documentation and examples for delete-by-query functionality using REST API.
This is not the case for Java Transport Client.
Where can I find usage examples for Java Transport Client ?
Does Java Transport Client cover whole ElasticSearch functionality like HTTP client via REST API?
The best practice of using Elasticsearch from Java: Follow This
Nexts:
You can follow the library : JEST
Yes, in maximum time, Java Transport Client cover whole ElasticSearch functionality like HTTP client via REST API
To complete #sunkuet02 answer:
As mentioned in documentation, the TransportClient is the preferred way if you're using java (performance, serialization, ...).
But the jar is quite heavy (with dependencies) and it requires that you use the same versions between client and server to work.
If you want a very lightweight client, there is a new Java REST client in Elastic 5.x.
I don't know the differences with Jest, but it's compatible with last Elastic 5.x versions (but not with previous versions) and it's developed by the Elastic team.
So it might be a good option to consider, according to your needs.
Related
Using google i found two possible solution for now:
-using spring boot with kotlin
-using this kotlin client https://github.com/jillesvangurp/kt-search
I've already finished the android client application in kotlin but now i have to find a way to make this client comunicate with elasticsearch.
What would it be the best solution for my problem that i could look up online
Thanks in advance
First, if you don't use Spring in the current application, integrating it (if possible) would be a lot of work and most likely not worth it.
Another alternative would be to use the officially supported Java client for Elasticsearch (https://www.elastic.co/guide/en/elasticsearch/client/java-api-client/current/index.html).
BUT, you should keep in mind that, if you put the Elasticsearch client in your client application, that the credentials, you may use, will also be in the client application.
They could be accessible for everyone using the Android client and the user could perform any request on the Elasticsearch. Also you couldn't change them without updating the client.
So, it is likely better to use a Three-Tier-Architecture (https://www.ibm.com/topics/three-tier-architecture) and creating an API service to handle the Elasticsearch requests.
my question is about different Elasticsearch client APIs .. I wanted to migrate form Elasticsearch 6.2 to Elasticsearch 7
Currently i am using JEST Client library with elasticsearch v6.2, but its absolute now therefore with the upgrade i wanted to used client library provided by Elasticsearch, but number of libraries provided by Elasticsearch make me lost which one to use with v7.15
these are following ES client libraries
Java client :
deprecated in 7.9
https://www.elastic.co/guide/en/elasticsearch/client/java-api/7.9/java-docs-index.html
REST clients: there are two REST clients
Low level REST client.
request marshalling and response un-marshalling is handled by the client
itself.
internally uses "Apache Http Async Client"
provide some basic domentation of rintailizing, request/response with java code
High Level client
deprecated in 7.15
it a layer on top of Low level client
performs request marshalling and response un-marshalling is handled by the client itself.
provides documentation with Java code
https://www.elastic.co/guide/en/elasticsearch/client/java-rest/7.15/java-rest-high-document-index.html
so its look like Elasticsearch 7.15 can only use "Low level REST client" because other two clients " Java client " and "RES High Level clien" are deprecated.
and using REST LOW level client require to write lots of basic codes like marschalling /un-marshalling etc
is my understating correct ?
is there any other Elasticsearch client available /better to use to migrate to 7.15 ?
You are right, this is the only way for this version.
But starting with 7.16 version there is a new client ⇾ ElasticsearchClient handling marshalling and unmarshalling by itself (You pass class type as a parameter with calls) with already pretty neet documentation existing:
https://www.elastic.co/guide/en/elasticsearch/client/java-api-client/master/connecting.html
I am curious to know which client should I use for elasticSearch using java API. There are multiples clients like Jest, Transport, ElasticSearch clients. Also I have to perform CRUD operations on ES.
You should use the java high level rest client as its an official Elasticsearch java client(that supports all documents CRUD operations).
JEST is not official client and not available for latest ES version(not even 7.0 while 7.8 is released so not keeping pace with ES versions).
Transport client is used by high level client and is getting deprecated mention in this official doc.
Please read this thread for more info on all these clients and how they work internally.
I am in a dilemma over to use spring's rest template or elasticsearch's own high/low rest client while searching in es . Does es client provide any advantage like HTTP connection pooling , performance while compared to spring rest template . Which of the two take less time in getting response from the server . Can some one please explain this ?
The biggest advantage of using Spring Data Elasticsearch is that you don't have to bother about the things like converting your requests/request bodies/responses from your POJO domain classes to and from the JSON needed by Elasticsearch. You just use the methods defined in the ElasticsearchOperations class which is implemented by the *Template classes.
Or going one abstraction layer up, use the Repository interfaces the all the Spring Data modules provide to store and search/retrieve your data.
Firstly, This is a very broad question. Not sure if it suits the SO guidelines.
But my two cents:
High Level Client uses Low Level client which does provide connection pooling
High Level client manages the marshalling and unmarshalling of the Elastisearch query body and response, so it might be easier to work using the APIs.
On the other hand, if you are familiar with the Elasticsearch querying by providing the JSON body then you might find it a bit difficult to translate between the JSON body and the Java classes used for creating the query (i.e when you are using Kibana console or other REST API tools)
I generally overcome this by logging the query generated by the Java API so that I can use it with Kibana console or other REST API tools.
Regarding which one is efficient- the library will not matter that much to affect the response times.
If you want to use Spring Reactive features and make use of WebClient, ES Libraries do provide support for Async search.
Update:
Please check the answer by Wim Van den Brande below. He has mentioned a very valid point of using Transport Client which has been deprecated over REST API.
So it would be interesting to see how RestTemplate or Spring Data ElasticSearch will update their API to replace TransportClient.
One important remark and caveat with regards to the usage of Spring Data Elasticsearch. Currently, Spring Data Elasticsearch doesn't support the communication by the High Level REST Client API. They are using the transport client. Please note, the TransportClient is deprecated as of Elasticsearch 7.0.0 and is expected to be removed in Elasticsearch 8.0!!!
FYI, this statement has been confirmed already by another post: Elasticsearch Rest Client with Spring Data Elasticsearch
Does anyone know of any benchmarks of using the native Elasticsearch driver over the rest client? I'm specifically working with the Java client but any other language would be fine.
If you are using Java then you can use native java client, which would be faster than HTTP Client. But if you are using any other language, then use REST Client would be faster, since client libraries in most programming languages use the HTTP Client themselves.