I have a two container and How I can access another container in python file with django web server
Docker-compose.yml file
version: '2'
services:
web:
build: ./web/
command: python3 manage.py runserver 0.0.0.0:8001
volumes:
- ./web:/code
ports:
- "8001:80"
networks:
- dock_net
container_name: con_web
depends_on:
- "api"
links:
- api
api:
build: ./api/
command: python3 manage.py runserver 0.0.0.0:8000
volumes:
- ./api:/code
ports:
- "8000:80"
networks:
- dock_net
container_name: con_api
networks:
dock_net:
driver: bridge
Python File:
I can get mail_string from form
mail = request.POST.get('mail_string', '')
url = 'http://con_api:8000/api/'+mail+'/?format=json'
resp = requests.get(url=url)
return HttpResponse(resp.text)
I request api container and get value but I dont know ip address
Updated Answer
In your python file, you can use url = 'http://api/'+mail+'/?format=json'. This will enable you to access the url you are trying to get request from.
Original Answer
If the two containers are independent, then you can create a network and when you make both the containers a part of same network then you can access them using their hostname which you can specify by --hostname=HOSTNAME.
Another easy way is to use docker-compose file which creates a network by default and all the services declared in the file are a part of that network. By that you can access other services by their service name. Simply like http://container1/ when your docker-compose file is like this:
version: '3'
services:
container1:
image: some_image
container2:
image: another_or_same_image
Now enter into container2 by:
docker exec -it container2 /bin/bash
and run ping http://contianer1
You will receive packets and therefore be able to access other container.
Related
I'm running an instance of a web application in my Docker container and am also running a MongoDB container so when I launch the web app I can easily connect to the DB on the app's connection page.
The issue is that I'm not sure how to reach the Mongo container from my web app and am not sure if my host/port connection info is correct.
My Docker Setup
As you can see the container is up and running with both mongo and web app services running without errors
I build the two through docker-compose.yml
version: "3.3"
services:
web:
image: grafana-asw-v3
container_name: grafana-asw-v3
restart: always
build: .
ports:
- "13000:3000"
volumes:
- grafana-storage:/var/lib/grafana
stdin_open: true
tty: true
db:
container_name: mongo
image: mongo
environment:
MONGO_INITDB_ROOT_USERNAME: root
MONGO_INITDB_ROOT_PASSWORD: example
volumes:
- grafana-mongo-db:/var/lib/mongo
ports:
- "27018:27017"
volumes:
grafana-mongo-db: {}
grafana-storage: {}
Issue
With everything up and running I'm attempting to connect through the web app, but I seem to be using the wrong connection info...
I assumed to use "hostMachine:port" (roxane:27018), but it's not connecting. Is there something I overlooked here?
There were two changes I had to make to fix this issue:
Modify the bind_ip in mongod.conf via making this change to my docker-compose file
db:
container_name: mongo
image: mongo
environment:
MONGO_INITDB_ROOT_USERNAME: root
MONGO_INITDB_ROOT_PASSWORD: example
volumes:
- grafana-mongo-db:/var/lib/mongo
ports:
- "27018:27017"
command: mongod --bind_ip 0.0.0.0
I needed to refer to the IP address instead of the hostname in the cli in my we application. (Thanks to this answer for help with this one)
Short answer
db service is in the same network than web service not in host network.
As you named your services via container_name you shoud be able to use the connection string mongodb://mongo:27017
Explanation
By default, docker containers run under a bridge network allowing them to communicate without viewing your host network.
When using ports in a compose file, you define that you want to map an internal port of the container to the host port
"27018:27017" => I want to expose the container port number 27017 to the host port number 27018.
As a result, you could expose your web frontend without exposing your mongo service :
version: "3.3"
services:
web:
image: grafana-asw-v3
container_name: grafana-asw-v3
restart: always
build: .
ports:
- "13000:3000"
volumes:
- grafana-storage:/var/lib/grafana
stdin_open: true
tty: true
db:
container_name: mongo
image: mongo
environment:
MONGO_INITDB_ROOT_USERNAME: root
MONGO_INITDB_ROOT_PASSWORD: example
volumes:
- grafana-mongo-db:/var/lib/mongo
volumes:
grafana-mongo-db: {}
grafana-storage: {}
Normally I'd have an instance neo4j running in Docker, then in a script I access the driver like so:
self.driver = GraphDatabase.driver(uri="bolt://localhost:7687", auth=("username", "password"))
I'm now putting this script itself into a Docker container, but I now get the error message:
neo4j.exceptions.ServiceUnavailable: Failed to establish connection to IPv6Address(('::1', 7687, 0, 0)) (reason [Errno 99] Cannot assign requested address)
What uri (or other parameter) needs changing to access a neo4 Docker instance, from another docker container?
Within my docker-compose.yml, I have:
version: '3'
services:
neo4j:
container_name: neo4j
image: neo4j:3.5
restart: always
environment:
- NEO4J_dbms_memory_pagecache_size=2G
- dbms_connector_bolt_tls__level=OPTIONAL
- NEO4J_dbms_memory_heap_max__size=3500M
- NEO4J_AUTH=neo4j/start
volumes:
- $HOME/neo4j/data:/data
- $HOME/neo4j/logs:/logs
- $HOME/neo4j/import:/import
- $HOME/neo4j/plugins:/plugins
ports:
- 7474:7474
- 7687:7687
appgui:
container_name: appgui
image: python:3.7.3-slim
build:
context: ./APPGUI/
volumes:
- ./APPGUI/:/usr/src/app/
restart: always
environment:
PORT: 5000
FLASK_DEBUG: 1
ports:
- 80:80
depends_on:
- neo4j
I also can't access my web app (http://localhost:5000)
Your service can't connect to localhost Neo4j, because it is inside a docker container, and localhost points to the docker containers instead of your local machine.
In this case, it is best to run both containers with docker-compose. You want to set the depends on feature in the other docker container. Here is an example docker-compose.yml file from my project.
version: '3.7'
services:
neo4j:
image: neo4j:4.1.2
restart: always
hostname: neo4jngs
container_name: neo4jngs
ports:
- 7474:7474
- 7687:7687
api:
build:
context: ./API
hostname: api
restart: always
container_name: api
ports:
- 3000:3000
depends_on:
- neo4j
As you can see, the api container is a service that will connect to Neo4j. Now you can change the driver settings to:
self.driver = GraphDatabase.driver(uri="bolt://neo4j:7687", auth=("username", "password"))
And you are good to go.
I solved it and it was actually a dumb mistake, but one that could happen to others I guess...
In the docker-compose.yml:
build: ./APP1/
needs to be in quotes, so:
build: './APP1/'
However Tomaž Bratanič provided me with some helpful tips to get a resolve.
I'm trying to get the X-Ms-Client-Principal-Name value from the request header but it doesn't come anymore after I change the container settings from Single Container to Docker Compose.
Any idea why is this happening?
This is the docker-compose file that I'm using:
version: "3.8"
services:
web:
image: webimage:v1.0.0
ports:
- "8000:80"
redis:
image: redis:alpine
Both images are correctly downloaded from the repository and launched
I'm making a React-Native app using Rest API (NodeJS, Express) and PostgreSQL.
Everything work good when hosted on my local machine.
Everything work good when API is host on my machine and PostgreSQL in docker container.
But when backend and frontend is both in docker, database is reachable from all my computer in local, but not by the backend.
I'm using docker-compose.
version: '3'
services:
wallnerbackend:
build:
context: ./backend/
dockerfile: ../Dockerfiles/server.dockerfile
ports:
- "8080:8080"
wallnerdatabase:
build:
context: .
dockerfile: ./Dockerfiles/postgresql.dockerfile
ports:
- "5432:5432"
volumes:
- db-data:/var/lib/postgresql/data
env_file: .env_docker
volumes:
db-data:
.env_docker and .env have the same parameters (just name changing).
Here is my dockerfiles:
Backend
FROM node:14.1
COPY package*.json ./
RUN npm install
COPY . .
CMD ["npm", "start"]
Database
FROM postgres:alpine
COPY ./wallnerdb.sql /docker-entrypoint-initdb.d/
I tried to change my hostname in connection url to postgres by using the name of the docker, my host IP address, localhost, but no results.
It's also the same .env (file in my node repo with db_name passwd etc) I do use in local to connect my backend to the db.
Since you are using NodeJS 14 in the Docker Container - make sure that you have the latest pg dependency installed:
https://github.com/brianc/node-postgres/issues/2180
Alternatively: Downgrade to Node 12.
Also make sure, that both the database and the "backend" are in the same network. Also: the backend should best "depend" on the database.
version: '3'
services:
wallnerbackend:
build:
context: ./backend/
dockerfile: ../Dockerfiles/server.dockerfile
ports:
- '8080:8080'
networks:
- default
depends_on:
- wallnerdatabase
wallnerdatabase:
build:
context: .
dockerfile: ./Dockerfiles/postgresql.dockerfile
ports:
- '5432:5432'
volumes:
- db-data:/var/lib/postgresql/data
env_file: .env_docker
networks:
- default
volumes:
db-data:
networks:
default:
This should not be necessary in you case - as pointed out in the comments - since Docker Compose already creates a default network
The container name "wallnerdatabase" is the host name of your database - if not configured otherwise.
I expect the issue to be in the database connection URL since you did not share it.
Containers in the same network in a docker-compose.yml can reach each other using the service name. In your case the service name of the database is wallnerdatabase so this is the hostname that you should use in the database connection URL.
The database connection URL that you should use in your backend service should be similar to this:
postgres://user:password#wallnerdatabase:5432/dbname
Also make sure that the backend code is calling the database using the hostname wallnerdatabase as it is defined in the docker-compose.yml file.
Here is the reference on Networking in Docker Compose.
You should access your DB using service name as hostname. Here is my working example - https://gitlab.com/gintsgints/vue-fullstack/-/blob/master/docker-compose.yml
My problem is I have a script that should scrap data and put it inside postgres database, however it has a problem to reach out postgres container.
When I run my docker-compose here is the result:
Name Command State Ports
------------------------------------------------------------------------------------------
orcsearch_dev-db_1 docker-entrypoint.sh postgres Up 0.0.0.0:5432->5432/tcp
orcsearch_flask_1 gunicorn wsgi:application ... Up 0.0.0.0:80->80/tcp, 8000/tcp
We can clearly see that postgres is on 5432 port.
This is my python script database setting:(ofcourse I removed password for obvious reason)
class App():
settings = {
'db_host': 'db',
'db_user': 'postgres',
'db_pass': '',
'db_db': 'orc',
}
db = None
proxies = None
and this is my docker-compose.yml
version: '2'
services:
flask:
build:
context: ./backend
dockerfile: Dockerfile.dev
volumes:
- ./backend:/app
- pip-cache:/root/.cache
ports:
- "80:80"
links:
- "dev-db:db"
environment:
- DATABASE_URL=postgresql://postgres#db:5432/postgres
stdin_open: true
command: gunicorn wsgi:application -w 1 --bind 0.0.0.0:80 --log-level debug --reload
networks:
app:
aliases:
- flask
dev-db:
image: postgres:9.5
ports:
- "5432:5432"
networks:
app:
aliases:
- dev-db
volumes:
pip-cache:
driver: local
networks:
app:
When going into exec flask bash(inside flask container) and running script command I get this error:
psycopg2.OperationalError: could not connect to server: No such file or directory
Is the server running locally and accepting
connections on Unix domain socket "/var/run/postgresql/.s.PGSQL.5432"?
Obviously there is postgres running on this port and I cant figure out what wrong do I do. Any help would be nice!
Probably you are using DSN instead of URI, and PostgreSQL thinks that "db" is not a host because it's hard to tell if "db" is host or path to socket. To fix it, use URI instead of DSN if you use >=9.2 version of PostgreSQL.
Example of URI:
postgresql://[user[:password]#][netloc][:port][/dbname][?param1=value1&...]
https://www.postgresql.org/docs/9.2/static/libpq-connect.html#LIBPQ-CONNSTRING
In your App class it should be 'db_host': 'dev-db', Seems like that hostname is exposed, not db.
I think that the problem is related to the fact that you're using the network and the link together. Try remove the link and change the postgres address to dev-db or change the alias to:
networks:
app:
aliases:
- dev-db
- db