I can't connect muy python app to postgres all run over docker, this is muy dockerfile:
FROM python:3.8
RUN mkdir /app
WORKDIR /app
ADD . /app/
ADD requirements.txt requirements.txt
RUN apt update -y
RUN pip install --upgrade pip
RUN pip install -r requirements.txt
My docker-compose
version: '3'
services:
db:
image: postgres:13.4-alpine
environment:
POSTGRES_PASSWORD: secret
POSTGRES_HOST_AUTH_METHOD: trust
env_file:
- .env
ports:
- "5432:5432"
volumes:
- ./database/init.sql:/docker-entrypoint-initdb.d/init.sql
app:
build: .
restart: always
depends_on:
- db
stdin_open: true
tty: true
env_file:
- .env
and my .env file
DB_NAME=database_dev
DB_USER=postgres
DB_PASSWORD=secret
DB_HOST=localhost
DB_PORT=5432
I'm trying to connect with SQLAlchemy, and this is the error
sqlalchemy.exc.OperationalError: (psycopg2.OperationalError) could not translate host name "{hostname}" to address: Name or service not known
edit
add my python code for connection, the env variables that I use are from .env file
class DatabaseManager:
def __init__(self):
self.db_url = 'postgresql+psycopg2://{user}:{password}\\@{hostname}/{database_name}'
self.db_url.format(
user=os.environ['DB_USER'],
password=os.environ['DB_PASSWORD'],
hostname=os.environ['DB_HOST'],
database_name=os.environ['DB_NAME']
)
self.engine = create_engine(self.db_url)
def make_session(self):
self.Session = sessionmaker(bind=self.engine)
self.session = self.Session()
def add_data(self, data):
self.session.add(data)
self.session.commit()
def close(self):
self.session.close()
