I have built a RESTful API web service using Flask framework, Redis as main database, MongoDB as a backup store and Celery as task queue to store data into MongoDB in background
Then I dockerize my application using docker-compose. Here is my docker-compose.yml:
version: '3'
services:
web:
build: .
ports:
- "5000:5000"
volumes:
- .:/app
redis:
image: "redis:alpine"
ports:
- "6379:6379"
mongo:
image: "mongo:3.6.5"
ports:
- "27017:27017"
environment:
MONGO_INITDB_DATABASE: syncapp
Here is my Dockerfile:
# base image
FROM python:3.5-alpine
MAINTAINER xhoix <145giakhang#gmail.com>
# copy just the requirements.txt first to leverage Docker cache
# install all dependencies for Python app
COPY ./requirements.txt /app/requirements.txt
WORKDIR /app
# install dependencies in requirements.txt
RUN pip install -r requirements.txt
# copy all content to work directory /app
COPY . /app
# specify the port number the container should expose
EXPOSE 5000
# run the application
CMD ["python", "/app/app.py"]
After run command docker-compose up, the app server, Redis and Mongo server just run well. But when I use Postman or curl to call the API, for example http://127.0.0.1:5000/sync/api/v1.0/users, which should return JSON format of all users, but the result is Could not get any response: There was an error connecting to http://127.0.0.1:5000/sync/api/v1.0/users.
I have no idea why this happens.
Thanks for any help and suggestion!
I found the cause of the issue:
After an hour debug, it turns out that I only need to change the app host to 0.0.0.0. Maybe when mapping port, docker default will be 0.0.0.0, since when I run command docker-compose ps, the PORTS column of each container has format 0.0.0.0:<port> -> <port>. I don't know this is the cause of the issue or not, but I did it and the problem is solved
If operating system Linux then use :
ifconfig -a
If operating system Windows then use :
ipconfig /all
Then check the interface like docker or something with virtualization, and use the ipv4 or inet
Or Just use the docker command:
docker network inspect bridge
Then use the gateway ip on IPAM
Related
I'm trying to run a database in docker and a python script with it to store MQTT messages. This gave me the idea to use Docker Compose since it sounded logical that both were somewhat connected. The issue I'm having is that the Docker Containers do indeed run, but they do not store anything in the database.
When I run my script locally it does store messages so my hunch is that the Compose File is not correct.
Is this the correct way to compose a python file which stores message in a DB and the database itself (with a .js file for the credentials). Any feedback would be appreciated!
version: '3'
services:
storing_script:
build:
context: .
dockerfile: Dockerfile
depends_on: [mongo]
mongo:
image: mongo:latest
environment:
MONGO_INITDB_ROOT_USERNAME: xx
MONGO_INITDB_ROOT_PASSWORD: xx
MONGO_INITDB_DATABASE: motionDB
volumes:
- ${PWD}/mongo-data:/data/db
- ./mongo-init.js:/docker-entrypoint-initdb.d/mongo-init.js:ro
ports:
- 27018:27018
restart: unless-stopped
The DockerFile im using to build:
# set base image (host OS)
FROM python:3.8-slim
# set the working directory in the container
WORKDIR /code
# copy the dependencies file to the working
directory
COPY requirements.txt .
# install dependencies
RUN pip install -r requirements.txt
# copy the content of the local src directory to
the working directory
COPY src/ .
# command to run on container start
CMD [ "python", "./main.py"]
I think this may be due to user permission.
What I did for my docker-compose for docker deployment, is I also mount the passwd file after creating a mongodb user
volumes:
/etc/passwd:/etc/passwd:ro
This worked for me as the most straight forward solution.
I want to be able to run a simple bash script within a container service on the hour using cron. I'm using Alpine Linux via docker-compose with a custom Dockerfile to produce a php-fpm based image, on which I hope to get crond running as well - except I can't.
Executing ps aux | grep cron on the container once built, returns nothing.
From what I understand, the usual Linux startup processes don't exist in Docker containers - fine - so how do I auto-start crond? Its dirs under /etc/periodic/ are created automatically, so I don't understand why the applicable process that consumes those dirs, isn't also running.
I tried creating a dedicated service definition within docker-compose.yml, which actually worked but the shell script to be run hourly needs access to a php binary which is running in a different container, so this isn't a viable solution.
If I shell into the container and run rc-service crond start I get this - but it never "finishes":
/var/www/html # rc-service crond start
* WARNING: crond is already starting
#> docker --version
Docker version 19.03.8, build afacb8b7f0
#> docker-compose --version
docker-compose version 1.23.2, build 1110ad01
I need a solution that I can place into my Dockerfile or docker-compose.yml files.
Dockerd is running on Ubuntu Xenial FWIW.
to run a cronjob container (Alpine), you need to make sure sure that the command of your docker container is
exec crond -f
if you want to add this to a docker file
CMD ["exec", "crond", "-f"]
you also may need to update the corn files before running the above command
Update based on the docker file and compose
To be able to solve your issues you need to update your docker-compose to have two containers one for cron and one for web
service_php_cron:
build:
context: .
dockerfile: .docker/services/php/Dockerfile.dev
container_name: base_service_php
command: 'cron_jobs'
volumes:
- ./app:/var/www/html/public
env_file:
- ./.env
# Low level container logging
logging:
driver: "json-file"
options:
max-size: "1m"
max-file: "5"
service_php:
build:
context: .
dockerfile: .docker/services/php/Dockerfile.dev
ports:
- "9000:9000"
command: 'web_server'
container_name: base_service_php
volumes:
- ./app:/var/www/html/public
env_file:
- ./.env
# Low level container logging
logging:
driver: "json-file"
options:
max-size: "1m"
max-file: "5"
you also need to update your docker file to be able to handle multiple commands using docker entry points
Add the below line to your docker file + remove the CMD one
COPY ./docker-entrypoint.sh /
RUN chmod a+x /docker-entrypoint.sh
ENTRYPOINT ["/docker-entrypoint.sh"]
and finally, create the entry point (make sure it hash execute permissions)
#!/bin/sh -e
case $1 in
web_server)
YOUR WEB SERVER COMMAND
;;
cron_jobs)
exec crond -f
;;
*)
exec "$#"
;;
esac
exit 0
you can check this link for more info about entrypoints
I have been writing this awesome Express & MongoDB app, just for fun,
1: https://github.com/mwaz/oober-bck, everything is working perfectly offline, I have different DB configurations for different application environments e.g, development, staging, testing, and production, in the real sense in every environment, the DB is different and given MongoDB is flexible, we do not have a problem with that.
Since the Application is working normally by setting the $NODE_ENV variable to the application environment required on my local machine, everything should work fine when the application is dockerized, however this is not the case, the mongoDB crashes at some point and does not connect to the application, here is the sample log
The Docker file is as follows:
FROM node:7
WORKDIR /app
COPY package.json /app
RUN npm install
COPY . /app
CMD node app.js
EXPOSE 3003
The docker-compose.yml file
version: "2"
services:
app:
container_name: oober
restart: always
build: .
ports:
- "3003:3003"
environment:
- NODE_ENV=STAGING
links:
- mongo
mongo:
container_name: mongo
image: mongo
ports:
- "27017:27017"
The docker image can be found on dockerhub using this link
docker pull sparatan/oober_app
Your default configuration of the staging database is DATABASE: "mongodb://localhost:27017/staging_ooberdb" as shown in your config.js file.
In a docker environment as you're using "localhost" will refer to the container itself (in this case your "oober" container.
You need to use the mongodb container name instead like this DATABASE: "mongodb://mongo:27017/staging_ooberdb" in the STAGING part of your config.js file.
As a side note, you probably don't want to expose the mongodb port in a production environment.
Hi I am getting this error when I try to run docker-compose up on my yml file.
This is my docker-compose.yml file
version: '3.6'
services:
phoenix:
# tell docker-compose which Dockerfile it needs to build
build:
context: .
dockerfile: Dockerfile.development
# map the port of phoenix to the local dev port
ports:
- 4000:4000
# mount the code folder inside the running container for easy development
volumes:
- . .
# make sure we start mongodb when we start this service
depends_on:
- db
db:
image: mongo:latest
volumes:
- ./data/db:/data/db
ports:
- 27017:27017
This is my Dockerfile:
# base image elixer to start with
FROM elixir:1.6
# install hex package manager
RUN mix local.hex --force
RUN mix local.rebar --force
# install the latest phoenix
RUN mix archive.install https://github.com/phoenixframework/archives/raw/master/phx_new.ez --force
# create app folder
COPY . .
WORKDIR ./
# install dependencies
RUN mix deps.get
# run phoenix in *dev* mode on port 4000
CMD mix phx.server
Is this a problem with my dev.exs setup or something to do with the compatibility of docker and phoenix / docker and mongodb?
https://docs.docker.com/compose/compose-file/#depends_on explicitly says:
There are several things to be aware of when using depends_on:
depends_on does not wait for db and redis to be “ready” before starting web - only until they have been started. If you need to wait for a service to be ready,
and advises you to implement the logic to wait for mongodb to spinup and be ready to accept connections by yourself: https://docs.docker.com/compose/startup-order/
In your case it could be something like:
CMD wait-for-db.sh && mix phx.server
where wait-for-db.sh can be as simple as
#!/bin/bash
until nc -z localhost 27017; do echo "waiting for db"; sleep 1; done
for which you need nc and wait-for-db.sh installed in the container.
There are plenty of other alternative tools to test if db container is listening on the target port.
UPDATE:
The network connection between containers is described at https://docs.docker.com/compose/networking/:
When you run docker-compose up, the following happens:
A network called myapp_default is created, where myapp is name of the directory where docker-compose.yml is stored.
A container is created using phoenix’s configuration. It joins the network myapp_default under the name phoenix.
A container is created using db’s configuration. It joins the network myapp_default under the name db.
Each container can now look up the hostname phoenix or db and get back the appropriate container’s IP address. For example, phoenix’s application code could connect to the URL mongodb://db:27017 and start using the Mongodb database.
It was an issue with my dev environment not connecting to the mongodb url specified in docker-compose. Instead of localhost, it should be db as named in my docker-compose.yml file
For clarity to dev env:
modify config/dev.exs to (replace with correct vars)
username: System.get_env("PGUSER"),
password: System.get_env("PGPASSWORD"),
database: System.get_env("PGDATABASE"),
hostname: System.get_env("PGHOST"),
port: System.get_env("PGPORT"),
create a dot env file on the root folder of your project (replace with relevant vars to the db service used)
PGUSER=some_user
PGPASSWORD=some_password
PGDATABASE=some_database
PGPORT=5432
PGHOST=db
Note that we have added port.
Host can be localhost but should be mongodb or db or even url when working on a docker-compose or server or k8s.
will update answer for prod config...
I utilize HapiJS via docker compose 2+
.env
NODE_VIEWS_PATH=../
NODE_PUBLIC_PATH=../
MONGODB_URI=mongodb://127.0.0.1:27017/mahrio
WEB_DOMAIN=http://127.0.0.1:6085
deep down somewhere I am setting the HapiJS stuff via these .env files, but for Docker I understand I need to do some changes.. no problem I made a docker specific version
docker.env
NODE_VIEWS_PATH=../
NODE_PUBLIC_PATH=../
MONGODB_URI=mongodb://mongo:27017/mahrio
WEB_DOMAIN=http://0.0.0.0:6085
I've tried 0.0.0.0 and 127.0.0.1 , neither work
I can see everything seems to work however when I goto localhost:6085 I get no response.
127.0.0.1 didn’t send any data.
Dockerfile
FROM node:carbon
# Create app directory
RUN mkdir -p /usr/src/mahrio
WORKDIR /usr/src/mahrio
COPY package*.json /usr/src/mahrio
RUN npm install
# If you are building your code for production
# RUN npm install --only=production
COPY . /usr/src/mahrio
EXPOSE 6085
CMD ["npm", "start"]
docker-compose.yml
version: "2"
services:
app:
build: .
container_name: mahrio
depends_on:
- mongo
env_file:
- docker.env
ports:
- "6085:6085"
restart: always
mongo:
container_name: mongo
image: mongo
volumes:
- ./tmp:/data/db
ports:
- "27017:27017"
any ideas ? No errors from nodejs are coming, everything looks A-OKAY at the console and I know it works outside docker just fine.
Edit: added the docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
25e7a4c3f350 mahriomedium_app "npm start" 24 hours ago Up About a minute 0.0.0.0:6085->6085/tcp mahrio
c8d691777aa0 mongo "docker-entrypoint..." 3 days ago Up About a minute 0.0.0.0:27017->27017/tcp mongo
docker logs
> mahrio-medium#0.0.1 start /usr/src/mahrio
> node server/index.js
Running Development!
MongoDB Config...
Server running at: http://127.0.0.1:6085
MongoDB connected!
db connection opened
it turned out WEB_DOMAIN was the wrong env var
the right var is NODE_URI to set to 0.0.0.0
all works now