How to properly run database (rethinkdb) with docker-compose? - docker

Question

I need help to run a database with docker and nodejs. I do not understand where I'm going wrong, but I can not make connection between my container with database and my container with node. This is the db link in docker: "https://hub.docker.com/_/rethinkdb/".Then follows:
my Dockerfile
FROM node:latest
ENV HOME=/src/jv-agricultor
RUN mkdir -p $HOME/
WORKDIR $HOME/
ADD package* $HOME/
RUN npm install
EXPOSE 80
ADD . $HOME/
CMD ["node", "node_modules/.bin/nodemon", "-L", "bin/www"]
My docker-compose.yml
version: "3"
volumes:
rethindb-data:
external: true
services:
db:
image: rethinkdb:latest
ports:
- "8080:8080"
- "29015:29015"
- "28015:28015"
api:
image: hello-nodemon
environment:
- NODE_ENV=development
- PORT=80
- DB_HOST=localhost
- DB_PORT=28015
deploy:
# replicas: 5
resources:
limits:
cpus: "0.1"
memory: 50M
restart_policy:
condition: on-failure
ports:
- "3000:80"
volumes:
- .:/src/jv-agricultor
- /src/jv-agricultor/node_modules
depends_on:
- db
networks:
- webnet
networks:
webnet:
i run: docker stack deploy -c docker-compose.yml webservice
My docker service
ID NAME MODE REPLICAS IMAGE PORTS
yez42a7w8khs webservice_api replicated 1/1 hello-nodemon:latest *:3000->80/tcp
n8idu78cp18m webservice_db replicated 1/1 rethinkdb:latest *:8080->8080/tcp,*:28015->28015/tcp,*:29015->29015/tcp
My docker service api (here is node/express)
ID NAME IMAGE NODE DESIRED STATE CURRENT STATE ERROR PORTS
p20qdagcspjc webservice_api.1 hello-nodemon:latest abner Running Running 28 minutes ago
My Docker service db
ID NAME IMAGE NODE DESIRED STATE CURRENT STATE ERROR PORTS
3046xuo4l8ix webservice_db.1 rethinkdb:latest abner Running Running 30 minutes ago
My logs internal db
webservice_db.1.3046xuo4l8ix#abner | Recursively removing directory /data/rethinkdb_data/tmp
webservice_db.1.3046xuo4l8ix#abner | Initializing directory /data/rethinkdb_data
webservice_db.1.3046xuo4l8ix#abner | Running rethinkdb 2.3.6~0jessie (GCC 4.9.2)...
webservice_db.1.3046xuo4l8ix#abner | Running on Linux 4.15.0-24-generic x86_64
webservice_db.1.3046xuo4l8ix#abner | Loading data from directory /data/rethinkdb_data
webservice_db.1.3046xuo4l8ix#abner | Listening for intracluster connections on port 29015
webservice_db.1.3046xuo4l8ix#abner | Listening for client driver connections on port 28015
webservice_db.1.3046xuo4l8ix#abner | Listening for administrative HTTP connections on port 8080
webservice_db.1.3046xuo4l8ix#abner | Listening on cluster addresses: 127.0.0.1, 172.18.0.3, 10.0.5.182, 10.0.5.183, 10.255.11.212, 10.255.11.213
webservice_db.1.3046xuo4l8ix#abner | Listening on driver addresses: 127.0.0.1, 172.18.0.3, 10.0.5.182, 10.0.5.183, 10.255.11.212, 10.255.11.213
webservice_db.1.3046xuo4l8ix#abner | Listening on http addresses: 127.0.0.1, 172.18.0.3, 10.0.5.182, 10.0.5.183, 10.255.11.212, 10.255.11.213
webservice_db.1.3046xuo4l8ix#abner | Server ready, "069fd360acfb_jot" c1cf5173-cf0d-457f-9c8f-4ba1756c28d8
my app.js
...
var connect = require('./lib/connect');
console.log('DB_HOST: ' + process.env.DB_HOST);
console.log('DB_PORT: ' + process.env.DB_PORT);
console.log('PORT: ' + process.env.PORT);
console.log('NODE_ENV: ' + process.env.NODE_ENV);
...
My connect middleware
'use strict'
// import r from 'rethinkdb';
var r = require('rethinkdb');
module.exports._connect = (function _connect(req, res, next) {
r.connect( {host: process.env.DB_HOST, port: process.env.DB_PORT}, (err, conn) => {
console.log(err);
})
})();
My service docker api logs respose
webservice_api.1.p20qdagcspjc#abner | [nodemon] restarting due to changes...
webservice_api.1.p20qdagcspjc#abner | [nodemon] starting `node bin/www`
webservice_api.1.p20qdagcspjc#abner | DB_HOST: localhost
webservice_api.1.p20qdagcspjc#abner | DB_PORT: 28015
webservice_api.1.p20qdagcspjc#abner | PORT: 80
webservice_api.1.p20qdagcspjc#abner | NODE_ENV: development
webservice_api.1.p20qdagcspjc#abner | { ReqlDriverError: Could not connect to localhost:28015.
webservice_api.1.p20qdagcspjc#abner | connect ECONNREFUSED 127.0.0.1:28015
webservice_api.1.p20qdagcspjc#abner | at ReqlDriverError.ReqlError [as constructor] (/src/jv-agricultor/node_modules/rethinkdb/errors.js:23:13)
webservice_api.1.p20qdagcspjc#abner | at new ReqlDriverError (/src/jv-agricultor/node_modules/rethinkdb/errors.js:68:50)
webservice_api.1.p20qdagcspjc#abner | at TcpConnection.<anonymous> (/src/jv-agricultor/node_modules/rethinkdb/net.js:94:27)
webservice_api.1.p20qdagcspjc#abner | at Object.onceWrapper (events.js:273:13)
webservice_api.1.p20qdagcspjc#abner | at TcpConnection.emit (events.js:182:13)
webservice_api.1.p20qdagcspjc#abner | at Socket.<anonymous> (/src/jv-agricultor/node_modules/rethinkdb/net.js:705:22)
webservice_api.1.p20qdagcspjc#abner | at Socket.emit (events.js:187:15)
webservice_api.1.p20qdagcspjc#abner | at emitErrorNT (internal/streams/destroy.js:82:8)
webservice_api.1.p20qdagcspjc#abner | at emitErrorAndCloseNT (internal/streams/destroy.js:50:3)
webservice_api.1.p20qdagcspjc#abner | at process._tickCallback (internal/process/next_tick.js:63:19)
webservice_api.1.p20qdagcspjc#abner | From previous event:
webservice_api.1.p20qdagcspjc#abner | at Function.<anonymous> (/src/jv-agricultor/node_modules/rethinkdb/net.js:945:10)
webservice_api.1.p20qdagcspjc#abner | at Function.connect (/src/jv-agricultor/node_modules/rethinkdb/util.js:43:16)
webservice_api.1.p20qdagcspjc#abner | at _connect (/src/jv-agricultor/lib/connect.js:9:7)
webservice_api.1.p20qdagcspjc#abner | at Object.<anonymous> (/src/jv-agricultor/lib/connect.js:19:3)
webservice_api.1.p20qdagcspjc#abner | at Module._compile (internal/modules/cjs/loader.js:689:30)
webservice_api.1.p20qdagcspjc#abner | at Object.Module._extensions..js (internal/modules/cjs/loader.js:700:10)
webservice_api.1.p20qdagcspjc#abner | at Module.load (internal/modules/cjs/loader.js:599:32)
webservice_api.1.p20qdagcspjc#abner | at tryModuleLoad (internal/modules/cjs/loader.js:538:12)
webservice_api.1.p20qdagcspjc#abner | at Function.Module._load (internal/modules/cjs/loader.js:530:3)
webservice_api.1.p20qdagcspjc#abner | at Module.require (internal/modules/cjs/loader.js:637:17)
webservice_api.1.p20qdagcspjc#abner | at require (internal/modules/cjs/helpers.js:20:18)
webservice_api.1.p20qdagcspjc#abner | at Object.<anonymous> (/src/jv-agricultor/app.js:14:15)
webservice_api.1.p20qdagcspjc#abner | at Module._compile (internal/modules/cjs/loader.js:689:30)
webservice_api.1.p20qdagcspjc#abner | at Object.Module._extensions..js (internal/modules/cjs/loader.js:700:10)
webservice_api.1.p20qdagcspjc#abner | at Module.load (internal/modules/cjs/loader.js:599:32)
webservice_api.1.p20qdagcspjc#abner | at tryModuleLoad (internal/modules/cjs/loader.js:538:12)
webservice_api.1.p20qdagcspjc#abner | at Function.Module._load (internal/modules/cjs/loader.js:530:3)
webservice_api.1.p20qdagcspjc#abner | at Module.require (internal/modules/cjs/loader.js:637:17)
webservice_api.1.p20qdagcspjc#abner | at require (internal/modules/cjs/helpers.js:20:18)
webservice_api.1.p20qdagcspjc#abner | name: 'ReqlDriverError',
webservice_api.1.p20qdagcspjc#abner | msg:
webservice_api.1.p20qdagcspjc#abner | 'Could not connect to localhost:28015.\nconnect ECONNREFUSED 127.0.0.1:28015',
webservice_api.1.p20qdagcspjc#abner | frames: undefined,
webservice_api.1.p20qdagcspjc#abner | message:
webservice_api.1.p20qdagcspjc#abner | 'Could not connect to localhost:28015.\nconnect ECONNREFUSED 127.0.0.1:28015' }

Answer 1

docker-compose does inter-service communication by service name, so the value of DB_HOST should be db.
On a side note, unless you need to expose the database outside of the stack, you do not need the port mapping.
#Alex Karshin It is unnecessary to fully specify the container name. The first example in the docker-compose networking docs shows how simple it really is.

Answer 2

spawnia has a point, but might not have the right answer. If you take a look at docker ps -a the name of your database container is webservice_db. Therefore, you will not be successful if you try to connect to rethinkdb on localhost (cuz obviously it's not on localhost).
You must either hardcode the container name (webservice_db) to your config file, or do set it in docker-compose.yml. But if you do, I suggest you set the container names explicitly:
version: "3"
...
services:
db:
container_name: webservice_db
...
api:
container_name: webservice_api
environment:
- NODE_ENV=development
- PORT=80
- DB_HOST= webservice_db
- DB_PORT=28015
...
There, now it should work normally.