I have an app that relies on 4 backend servers (redis, mongo, graphql-websockets-subscriptions, and graphql-http) and one front end
Not configuring networks, I am able to connect my different servers while I'm in the same container, but I cannot access the mongodb database from the front-end compose-container with the url: mongodb://weallyback_default:27017/weally
This is my front-end compose config
version: "3.8"
services:
next_server:
image: node:14.17.3-alpine
volumes:
- type: bind
source: ./
target: /front
- type: volume
source: nodemodules # name of the volume, see below
target: /front/node_modules
volume:
nocopy: true
working_dir: /front
command: yarn dev
ports:
- "3000:3000"
networks:
- weallyback_default
environment:
- NODE_ENV=development
- PORT=3000
volumes:
nodemodules:
networks:
weallyback_default:
external: true
Knowing that my backend config exposes the default network weallyback_default
D:\Zied\work\WeAllyBack>docker network ls
NETWORK ID NAME DRIVER SCOPE
71d1c5f23159 bridge bridge local
cd980f642e7b host host local
4a50359ad823 none null local
ecec643b2a2e weallyback_default bridge local
That led me to attempt to configure networks, but that broke even connections between instances in the same container:
From what I understood, I have to declare networks as external if I want to use them in a different docker-compose file. So I started naming my networks, but I can't get it to work anyways:
So I appended these networks declarations to the front-end (weallyorg_next_server_1) server's config
networks:
graphql_server:
external: true
graphql_pubsub_server:
external: true
mongo_server:
external: true
This is the config for my 4 backend servers:
version: "3.8"
services:
redis-server:
container_name: redis-server
image: 'redis:6.2-alpine'
ports:
- "6379:6379"
networks:
- redis_server
mongo-server:
container_name: mongo-server
image: mongo:4.4.5
ports:
- "27001:27001"
volumes:
- mongodb:/data/db
- mongodb_config:/data/configdb
networks:
- mongo_server
restart: always
graphql_server:
container_name: graphql_server
depends_on:
- mongo-server
- redis-server
image: node:14.17.3-alpine
volumes:
- type: bind
source: ./
target: /app
- type: volume
source: nodemodules # name of the volume, see below
target: /app/node_modules
volume:
nocopy: true
working_dir: /app
command: yarn dev
ports:
- "4000:4000"
networks:
- graphql_server
- mongo_server
environment:
- NODE_ENV=development
- PORT=4000
graphql_pubsub_server:
container_name: graphql_pubsub_server
depends_on:
- mongo-server
- redis-server
image: node:14.17.3-alpine
volumes:
- type: bind
source: ./
target: /app
- type: volume
source: nodemodules # name of the volume, see below
target: /app/node_modules
volume:
nocopy: true
working_dir: /app
command: yarn dev-sub
ports:
- "4001:4001"
networks:
- graphql_pubsub_server
- mongo_server
- redis_server
environment:
- NODE_ENV=development
- PORT=4000
volumes:
nodemodules:
mongodb:
mongodb_config:
networks:
graphql_server:
name: graphql_server
driver: bridge
graphql_pubsub_server:
name: graphql_pubsub_server
driver: bridge
mongo_server:
name: mongo_server
driver: bridge
redis_server:
name: redis_server
driver: bridge
When I try to connect the graphql servers to mongo and redis, it doesn't work:
const DEV_URL_LOCAL = 'mongodb://mongo-server:27017/weally';
export const pubsub = new RedisPubSub({connection:{
host: 'redis-server',
port: 6379
}});
Even though the networks seem to be ok when I run docker network inspect, I see the front-end instance weallyorg_next_server_1 associated in the containers list:
D:\Work\WeAllyBack>docker network ls
NETWORK ID NAME DRIVER SCOPE
2dbd93a99f96 bridge bridge local
58c1d94a2f2e graphql_pubsub_server bridge local
62d20fee3c3a graphql_server bridge local
b16be840cbd1 host host local
655197efa0d7 mongo_server bridge local
c2c845f1c14c none null local
0b95acfd581d redis_server bridge local
ee7d85a80a09 weallyback bridge local
D:\Work\WeAllyBack>docker network inspect mongo_server
[
{
"Name": "mongo_server",
"Id": "655197efa0d7c0070ea3a5e2fba565c117bde72efaf4e5952fe6e2c1499199a0",
"Created": "2021-08-02T12:05:15.397633Z",
"Scope": "local",
"Driver": "bridge",
"EnableIPv6": false,
"IPAM": {
"Driver": "default",
"Options": null,
"Config": [
{
"Subnet": "172.20.0.0/16",
"Gateway": "172.20.0.1"
}
]
},
"Internal": false,
"Attachable": true,
"Ingress": false,
"ConfigFrom": {
"Network": ""
},
"ConfigOnly": false,
"Containers": {
"438cdfa8fc24ef3c2a537c3746f2a82e29bdb29e6c925e34587531819f96cfa3": {
"Name": "graphql_pubsub_server",
"EndpointID": "05ce92ae14016d6144c97748e5a1718a62ab4fc14d6518d2b33bd2f2077fb229",
"MacAddress": "02:42:ac:14:00:05",
"IPv4Address": "172.20.0.5/16",
"IPv6Address": ""
},
"b71e428de30e01b13c1cc83ecc083baac88fdb7f01a0385a0984000e24dc2f52": {
"Name": "mongo-server",
"EndpointID": "cac16e9c451f24a708d5b678b69beb54358f49960700e240975c4634bb90b9ac",
"MacAddress": "02:42:ac:14:00:02",
"IPv4Address": "172.20.0.2/16",
"IPv6Address": ""
},
"ee8ef82c6751946d68a7ec295d266306ef992bc30f3314eeb432080db42db877": {
"Name": "graphql_server",
"EndpointID": "5a198664afc78c8f8b23682288f4ea42f0253e448b4968c0af3e2f878d8835a8",
"MacAddress": "02:42:ac:14:00:04",
"IPv4Address": "172.20.0.4/16",
"IPv6Address": ""
},
"f2405fe94eb5c7638b8cad062665a35b224b86b887822ed384c9a840d1eab622": {
"Name": "weallyorg_next_server_1",
"EndpointID": "df8930f6e5bc141cf2992fd81c552ee58944e9c5036a64f0a09ca9206e2808c0",
"MacAddress": "02:42:ac:14:00:03",
"IPv4Address": "172.20.0.3/16",
"IPv6Address": ""
}
},
"Options": {},
"Labels": {
"com.docker.compose.network": "mongo_server",
"com.docker.compose.project": "weallyback",
"com.docker.compose.version": "1.29.2"
}
}
]
I'm new to Docker, so I'm really confused about whet to do next...
Please note that if I remove the network specific settings everything works fine, I just want to have my front end server configuration in a different docker-compose file, so I want to name the networks to access them from the other (front end) container. This config works for redis-server:6379 and mongodb://mongo-server:27017/weally urls:
version: "3.8"
services:
redis-server:
image: 'redis:6.2-alpine'
ports:
- "6379:6379"
mongo-server:
image: mongo:4.4.5
ports:
- "27001:27001"
volumes:
- mongodb:/data/db
- mongodb_config:/data/configdb
restart: always
graphql_server:
depends_on:
- mongo-server
- redis-server
image: node:14.17.3-alpine
volumes:
- type: bind
source: ./
target: /app
- type: volume
source: nodemodules # name of the volume, see below
target: /app/node_modules
volume:
nocopy: true
working_dir: /app
command: yarn dev
ports:
- "4000:4000"
environment:
- NODE_ENV=development
- PORT=4000
graphql_pubsub_server:
depends_on:
- mongo-server
- redis-server
image: node:14.17.3-alpine
volumes:
- type: bind
source: ./
target: /app
- type: volume
source: nodemodules # name of the volume, see below
target: /app/node_modules
volume:
nocopy: true
working_dir: /app
command: yarn dev-sub
ports:
- "4001:4001"
environment:
- NODE_ENV=development
- PORT=4000
volumes:
nodemodules:
mongodb:
mongodb_config:
This gives theses networks after pruning
> docker network ls
NETWORK ID NAME DRIVER SCOPE
71d1c5f23159 bridge bridge local
cd980f642e7b host host local
4a50359ad823 none null local
e4cf4a71d49a weallyback_default bridge local
I suspect the format of my connection url to be wrong but I can't find the info to set it right. I've red some tutorials like this one, and my urls should be correct, I can't figure out what is missing
Ok!!!
So it seems bridge doesn't resolve names
The downside with the bridge driver is that it’s not recommended for production; the containers communicate via IP address instead of automatic service discovery to resolve an IP address to the container name.
https://earthly.dev/blog/docker-networking/
more details are available here: https://docs.docker.com/network/network-tutorial-standalone/