Failed to open TCP connection to localhost:9200 - Rails on Docker - ruby-on-rails

Question

I 'm want to run ElasticSearch on docker and connect rails with it.
this is my docker-compose.yml file
version: '3'
services:
db:
image: mysql:5.7
restart: always
environment:
MYSQL_ROOT_PASSWORD: P#ssw0rd
MYSQL_DATABASE: chatsystem
MYSQL_USER: root
MYSQL_PASSWORD: P#ssw0rd
ports:
- "3307:3306"
es01:
image: docker.elastic.co/elasticsearch/elasticsearch:7.4.2
container_name: es01
environment:
- node.name=es01
- cluster.name=es-docker-cluster
- discovery.seed_hosts=es02,es03
- cluster.initial_master_nodes=es01,es02,es03
- bootstrap.memory_lock=true
- "ES_JAVA_OPTS=-Xms512m -Xmx512m"
ulimits:
memlock:
soft: -1
hard: -1
volumes:
- data01:/usr/share/elasticsearch/data
ports:
- 9200:9200
networks:
- elastic
es02:
image: docker.elastic.co/elasticsearch/elasticsearch:7.4.2
container_name: es02
environment:
- node.name=es02
- cluster.name=es-docker-cluster
- discovery.seed_hosts=es01,es03
- cluster.initial_master_nodes=es01,es02,es03
- bootstrap.memory_lock=true
- "ES_JAVA_OPTS=-Xms512m -Xmx512m"
ulimits:
memlock:
soft: -1
hard: -1
volumes:
- data02:/usr/share/elasticsearch/data
networks:
- elastic
es03:
image: docker.elastic.co/elasticsearch/elasticsearch:7.4.2
container_name: es03
environment:
- node.name=es03
- cluster.name=es-docker-cluster
- discovery.seed_hosts=es01,es02
- cluster.initial_master_nodes=es01,es02,es03
- bootstrap.memory_lock=true
- "ES_JAVA_OPTS=-Xms512m -Xmx512m"
ulimits:
memlock:
soft: -1
hard: -1
volumes:
- data03:/usr/share/elasticsearch/data
networks:
- elastic
app:
build: .
command: bundle exec rails s -p 3000 -b '0.0.0.0'
volumes:
- ".:/ChatSystem"
depends_on:
- db
- es01
- es02
- es03
ports:
- "3000:3000"
links:
- db
- es01
- es02
- es03
environment:
DB_USER: root
DB_NAME: chatsystem
DB_PASSWORD: P#ssw0rd
DB_HOST: db
volumes:
data01:
driver: local
data02:
driver: local
data03:
driver: local
networks:
elastic:
driver: bridge
When I run docker-compose up and access localhost:9200 through the browser. I get this response
{
"name": "es01",
"cluster_name": "es-docker-cluster",
"cluster_uuid": "fNDAvsI6QUyHkzy919PHhw",
"version": {
"number": "7.4.2",
"build_flavor": "default",
"build_type": "docker",
"build_hash": "2f90bbf7b93631e52bafb59b3b049cb44ec25e96",
"build_date": "2019-10-28T20:40:44.881551Z",
"build_snapshot": false,
"lucene_version": "8.2.0",
"minimum_wire_compatibility_version": "6.8.0",
"minimum_index_compatibility_version": "6.0.0-beta1"
},
"tagline": "You Know, for Search"
}
When i try create new "message" i get this error
Errno::EADDRNOTAVAIL (Failed to open TCP connection to localhost:9200 (Cannot assign requested address - connect(2) for "localhost" port 9200))
message.rb file
class Message < ApplicationRecord
include Elasticsearch::Model
include Elasticsearch::Model::Callbacks
settings do
mappings dynamic: false do
indexes :message, type: :text
end
end
end
Message.import force: true
I 'm using this gems
gem 'elasticsearch-model', git: 'git://github.com/elastic/elasticsearch-rails.git', branch: 'master'
gem 'elasticsearch-rails', git: 'git://github.com/elastic/elasticsearch-rails.git', branch: 'master'

Answer 1

On your environment you must add ELASTICSEARCH_URL=http://elasticsearch:9200 and then rebuild your docker compose. You can take this article as reference.