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django.db.utils.OperationalError after makemigrations

I am trying to python manage.py makemigrations for a django app in postgres, but I am getting the follow error:
django.db.utils.OperationalError: connection to server at "localhost" (::1), port 5432 failed: FATAL: database "backend_db" does not exist
Before this, I am doing docker compose up with the following docker-compose and .env file:
version: '3.2'
services:
postgres:
image: postgres:13.4
environment:
POSTGRES_DB: backend_db
POSTGRES_USER: postgres
POSTGRES_PASSWORD: postgres
volumes:
- database-data:/var/lib/postgresql/data/
ports:
- 5432:5432
networks:
- postgres
volumes:
database-data:
driver: local
networks:
postgres:
driver: bridge
DB_NAME='backend_db'
DB_USER='postgres'
DB_PASSWORD='postgres'
# DB_HOST is localhost or the IP of the machine running postgres
DB_HOST='localhost'
DB_PORT='5432'
The part of the settings.py that I define the postgres is the following:
DATABASES = {
'default': get_config(
'DATABASE_URL',
'sqlite:///' + BASE_DIR.child('db.sqlite3'),
cast=db_url
),
'postgres': {
'ENGINE': 'django.db.backends.postgresql_psycopg2',
'NAME': get_config('DB_NAME', 'backend_db'),
'USER': get_config('DB_USER', 'postgres'),
'PASSWORD': get_config('DB_PASSWORD', 'postgres'),
'HOST': get_config('DB_HOST', 'postgres-service'),
'PORT': get_config('DB_PORT', '5432')
}
}
Any idea of what causes the error?

I believe you can use:
docker-compose run web python manage.py makemigrations
You may need to change web to your appropriate service.

I encountered the same problem, and it turns out that in my case, there was a PostgreSQL server (via Postbird) running on my local machine and the python server was inadvertently connecting to it instead of to the one in the Docker container. Context: I normally run my python app natively (i.e., locally with python manage.py runserver) and database services in a Docker container, connected to via port forwarding.
The solution was to kill the local Postgres instance and let the python server connect to the Docker instance

Is the server running on host "localhost" (::1) and accepting TCP/IP connections on port 5432? in Django [duplicate]

I'm very new for docker, now I am trying to run django with mariadb in docker through docker-compose, but I always get this error:
I use Docker version 17.09.1-ce, build 19e2cf6, docker-compose version 1.18.0, build 8dd22a9
django.db.utils.OperationalError: (2003, 'Can\'t connect to MySQL
server on \'mariadb55\' (111 "Connection refused")')
I can connect db correctly after run docker-compose up db in local or remote, and I even can run python manage.py runserver 0.0.0.0:6001 correctly in anaconda virtual environment to connect db service in docker by setting parameters of settings.py file like below:
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.mysql',
'NAME': 'test',
'USER': 'belter',
# 'HOST': 'mariadb55',
'HOST': '127.0.0.1',
'PORT': '3302',
'PASSWORD': 'belter_2017',
'default-character-set': 'utf8',
'OPTIONS': {
'sql_mode': 'traditional',
}
}
}
This is my docker-compose.yml file
version: '3'
services:
db:
image: mariadb:5.5
restart: always
environment:
- MYSQL_HOST=localhost
- MYSQL_PORT=3306
- MYSQL_ROOT_HOST=%
- MYSQL_DATABASE=test
- MYSQL_USER=belter
- MYSQL_PASSWORD=belter_2017
- MYSQL_ROOT_PASSWORD=123456_abc
volumes:
- /home/belter/mdbdata/mdb55:/var/lib/mysql
ports:
- "3302:3306"
web:
image: onlybelter/django_py35
command: python3 manage.py runserver 0.0.0.0:6001
volumes:
- /mnt/data/www/mysite:/djcode
ports:
- "6001:6001"
depends_on:
- db
links:
- db:mariadb55
I almost tried everything I can find, but still cannot figure it out, any help would be nice!
What I have tried:
Docker compose mysql connection failing
Linking django and mysql containers using docker-compose
Django connection to postgres by docker-compose

Finally, I figured it out!
The key point is, just as #SangminKim said, I need to use 3306 not 3302 in settings.py, and use db as HOST not 127.0.0.1.
So this is my docker-compose.yml file now:
version: '3'
services:
db:
image: mariadb:5.5
restart: always
environment:
- MYSQL_HOST=localhost
- MYSQL_PORT=3306 # cannot change this port to other number
- MYSQL_ROOT_HOST=%
- MYSQL_DATABASE=test
- MYSQL_USER=belter
- MYSQL_PASSWORD=belter_2017
- MYSQL_ROOT_PASSWORD=123456_abc
volumes:
- /home/belter/mdbdata/mdb55:/var/lib/mysql
ports:
- "3302:3306"
web:
image: onlybelter/django_py35
command: python3 manage.py runserver 0.0.0.0:6001
volumes:
- .:/djcode
ports:
- "6001:6001"
depends_on:
- db
So now we can connect this docker-mysql by mysql -h 127.0.0.1 -P 3302 -u root -p in shell directly, but we have to use db and 3306 in django settings.py file:
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.mysql',
'NAME': 'test',
'USER': 'belter',
# 'HOST': 'mariadb55',
'HOST': 'db', #<---
'PORT': '3306', #<---
'PASSWORD': 'belter_2017',
'default-character-set': 'utf8',
'OPTIONS': {
'sql_mode': 'traditional',
}
}
}
And we can still check if this port is open, by running extra command in docker-compose.yml file:
...
web:
image: onlybelter/django_py35
command: /bin/sh -c "python check_db.py --service-name mysql --ip db --port 3306"
volumes:
- .:/djcode
...
Here is check_db.py file:
# check_db.py
import socket
import time
import argparse
""" Check if port is open, avoid docker-compose race condition """
parser = argparse.ArgumentParser(description='Check if port is open, avoid\
docker-compose race condition')
parser.add_argument('--service-name', required=True)
parser.add_argument('--ip', required=True)
parser.add_argument('--port', required=True)
args = parser.parse_args()
# Get arguments
service_name = str(args.service_name)
port = int(args.port)
ip = str(args.ip)
# Infinite loop
while True:
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
result = sock.connect_ex((ip, port))
if result == 0:
print("{0} port is open! Bye!".format(service_name))
break
else:
print("{0} port is not open! I'll check it soon!".format(service_name))
time.sleep(3)
By the way, this is my Dockerfile for build django-py35:
FROM python:3.5-alpine
MAINTAINER Xin Xiong "xiongxin20008#126.com"
ENV PYTHONUNBUFFERED 1
RUN set -e; \
apk add --no-cache --virtual .build-deps \
gcc \
libc-dev \
linux-headers \
mariadb-dev \
python3-dev \
postgresql-dev \
freetype-dev \
libpng-dev \
g++ \
;
RUN mkdir /djcode
WORKDIR /djcode
ENV REFRESHED_AT 2017-12-25
ADD requirements.txt /djcode/
RUN pip install --no-cache-dir -r /djcode/requirements.txt
RUN pip install uwsgi
ADD . /djcode/ # copy . to /djcode/
EXPOSE 6001
See more details from here: https://github.com/OnlyBelter/django-compose

You should use the container name instead of localhost (or 127.0.0.1) in your settings.py file. Try providing a container name to the db service in the docker-compose.yml file using container_name attribute and replace the host name in the settings.py by the value of the container_name. (Make sure that they are in the same network that docker compose creates for you.)

Build container with this:
docker run --name mysql-latest \
-p 3306:3306 -p 33060:33060 \
-e MYSQL_ROOT_HOST='%' -e MYSQL_ROOT_PASSWORD='strongpassword' \
-d mysql/mysql-server:latest
Make sure MYSQL_ROOT_HOST='%', that means root can connect from any IP.

2002, "Can't connect to local MySQL server through socket '/run/mysqld/mysqld.sock' (2)" in docker-compose up

I'm trying to start the server through docker-compose up
I'm get an error:
2002, "Can't connect to local MySQL server through socket '/run/mysqld/mysqld.sock' (2)"
docker-compose.yml
version: '3'
services:
db:
image: mysql:5.7
environment:
MYSQL_DATABASE: 'slack_bot1'
MYSQL_USER: 'root'
MYSQL_PASSWORD: ''
MYSQL_ROOT_PASSWORD: '****'
volumes:
- /opt/slack_bot/mysql_data:/var/lib/mysql
redis:
image: "redis:alpine"
volumes:
- /opt/slack_bot/redis_data:/var/lib/redis
web:
build: .
command: python manage.py runserver 0.0.0.0:8001
ports:
- "8001:8001"
depends_on:
- db
Dockerfile
FROM python:3.7-alpine
ENV PYTHONUNBUFFERED 1
WORKDIR /home/slack_bot
ADD requirements.txt /home/slack_bot/
RUN set -e; \
apk add --no-cache --virtual .build-deps \
gcc \
libc-dev \
linux-headers \
mariadb-dev \
python3-dev \
;
RUN pip install -r requirements.txt
ADD . /home/slack_bot/
EXPOSE 8001
CMD ["python", "manage.py", "runserver", "0.0.0.0:8001"]
docker ps log
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
68b61ca0ce74 slack_bot_web "python manage.py ru…" 8 minutes ago Up 32 seconds 0.0.0.0:8001->8001/tcp slack_bot_web_1
c5f254a527b0 mysql:5.7 "docker-entrypoint.s…" 8 minutes ago Up 34 seconds 3306/tcp, 33060/tcp slack_bot_db_1
4cbc1fa3765e redis:alpine "docker-entrypoint.s…" 15 minutes ago Up 33 seconds 6379/tcp slack_bot_redis_1
Django settings of database
'ENGINE': 'django.db.backends.mysql',
'NAME': 'slack_bot1',
'USER': 'root',
'PASSWORD': '',
'HOST': '',
'PORT': '',

In your django settings, you leave database host as EMPTY, then the default value would be localhost. When use localhost, mysql client driver will connect mysql server with unix socket not tcp.
So, for your case you need to export unix socket in your mysql container to volume, then your django app container utilize this volume to share the unix socket.
Next is what you needed to do:
Manual new a folder which later as volume to share your unix socket file
(IMPORTANT: you could not rely on docker-compose to new this folder, you will encountered permission error)
mkdir -p /tmp/slack_bot/mysqld && chmod -R 777 /tmp/slack_bot/mysqld
In your docker-compose.yaml, add one more volume to mysql service:
db:
image: mysql:5.7
environment:
MYSQL_DATABASE: 'slack_bot1'
MYSQL_USER: 'root'
MYSQL_PASSWORD: ''
MYSQL_ROOT_PASSWORD: '****'
volumes:
- /opt/slack_bot/mysql_data:/var/lib/mysql
- /tmp/slack_bot/mysqld:/var/run/mysqld
In your docker-compose.yaml, add one more volume to web service:
web:
build: .
command: python manage.py runserver 0.0.0.0:8001
ports:
- "8001:8001"
depends_on:
- db
volumes:
- /tmp/slack_bot/mysqld:/run/mysqld
NOTE: here you say you get the error /run/mysqld/mysqld.sock as next, I'm not sure if you paste the all log as most offen it could be /var/run/mysqld/mysqld.sock, nertheless, if the error is /var/run/mysqld/mysqld.sock then you should modify above example volume to - /tmp/slack_bot/mysqld:/var/run/mysqld
2002, "Can't connect to local MySQL server through socket '/run/mysqld/mysqld.sock' (2)"
With above, now your web service could share the unix socket in mysql container.
Additional, configure HOST as db I think also could be another solution, just unix socket is much faster compared to use tcp.

I was able to connect django and db docker containers which are in the same machine but aren't in the same docker-compose file by the following steps:
Use host.docker.internal as host in settings.py instead of localhost as following:
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.mysql',
'NAME': 'dbName',
'USER': 'dbUser',
'PASSWORD': 'dbUserPassword',
'HOST': 'host.docker.internal',
'PORT': '3306'
}
}
Expose the port in db compose-file
ports:
- 3306:3306

Migration from MySQL to postgresql using Django and Docker - relation "authtoken_token" does not exist

I am trying to migrate my Django project using MySQL database to postgresql with Docker. When I use MySQL everything works fine. I have all in ORM so when I use MySQL I have to create only database and do python manage.py makemigrations and then python manage.py migrate and I get ready database with all relations. As I have mentioned I'm trying to use postgresql database. Server seems to work fine using docker-compose up, but when I send for instance GET request I get:
ProgrammingError at /data
relation "authtoken_token" does not exist
LINE 1: ...user"."is_active", "auth_user"."date_joined" FROM "authtoken...
My settings:
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.postgresql',
'NAME': 'postgres',
'USER': 'postgres',
'HOST': 'db',
'PORT': 5432,
}
}
My docker-compose.yml:
version: '3'
services:
db:
image: postgres
web:
build: .
command: python3 DIR/backend/dir/manage.py runserver 0.0.0.0:8000
volumes:
- .:/code
ports:
- "8000:8000"
depends_on:
- db
Dockerfile:
FROM python:3.6.1
ENV PYTHONUNBUFFERED 1
RUN mkdir /code
WORKDIR /code
ADD requirements.txt /code/
RUN pip3 install -r requirements.txt
ADD . /code/
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
f364a72186ce dockerpri_web "python3 PROJECT/backe..." 19 seconds ago Up 18 seconds 0.0.0.0:8000->8000/tcp dockerpri_web_1
774ae20bcaa3 postgres "docker-entrypoint..." 9 hours ago Up 19 seconds 5432/tcp dockerpri_db_1
MacBook-Pro:DockerPROJECT myName$ docker exec -ti dockerproject_web_1 /bin/bash
root#f364a72186ce:/code#

Django can't connect to Postgres in Docker setup

I'm setting up an application in Docker that uses Django and Postgres. I'm unable to connect to Postgres from the app. When I run either:
docker-compose run web python manage.py runserver
docker-compose run web python manage.py migrate
I get the following error:
django.db.utils.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"?
Here's my Dockerfile:
FROM python:2.7
ADD requirements.txt /app/requirements.txt
WORKDIR /app/
RUN pip install -r requirements.txt
My docker-compose.yml:
version: '2'
services:
db:
image: postgres:9.4
hostname: db
environment:
- POSTGRES_USER=postgres
- POSTGRES_PASSWORD=postgres
- POSTGRES_DB=postgres
ports:
- "5432:5432"
web:
build:
context: .
dockerfile: Dockerfile
hostname: web
volumes:
- .:/app
ports:
- "8000:8000"
links:
- db
depends_on:
- db
command:
python manage.py runserver 0.0.0.0:8000
and the database settings in Django:
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.postgresql_psycopg2',
'NAME': 'postgres',
'USER': 'postgres',
'HOST': 'db',
'PORT': 5432,
}
}
docker ps -a shows:
e9df7e1644ce web "python manage.py ..." About a minute ago Up About a minute 0.0.0.0:8000->8000/tcp web_1
60801d3256e4 postgres:9.4 "docker-entrypoint..." About a minute ago Up About a minute 0.0.0.0:5432->5432/tcp db_1
Django v1.10.5
Docker for Mac v1.13.1
docker-compose v 1.11.1
Here are the logs:
web: https://gist.github.com/steven-mercatante/912ca964fd05bee2c835b1ac5586c154
db: https://gist.github.com/steven-mercatante/4c9a03bfc4f2e90f4b9931bdc185652f

Turns out the issue was that Postgres hadn't fully spun up before starting the Django app. This was easily solved by waiting a few seconds before starting the web server. I set the command for my web service to ./bin/boot.sh, and the contents of that file are:
#!/bin/sh
# wait for Postgres to start
sleep 10
python manage.py migrate
python manage.py runserver 0.0.0.0:8000
Edit
This method might not be good enough depending on your application - sleeping for 10 seconds works for me, most of the time, but it's possible that postgres will take 11 seconds to spin up. Here's an improved bash file, with a function I took from this example.
#!/bin/bash
# wait for Postgres to start
function postgres_ready(){
python << END
import sys
import psycopg2
try:
conn = psycopg2.connect(dbname="postgres", user="postgres", password="postgres", host="postgres")
except psycopg2.OperationalError:
sys.exit(-1)
sys.exit(0)
END
}
until postgres_ready; do
>&2 echo "Postgres is unavailable - sleeping"
sleep 1
done
python manage.py migrate
gunicorn pft.wsgi:application -w 2 -b 0.0.0.0:8000 --reload

I had this problem and it was only because I was using a VPN. If you are using something like sshuttle just turn it off.