I have Java SpringBoot Web-application working on host machine. Application connects to PostgreSQL database. All works well. OS - Ubuntu 18.
Now i need to move application in Docker container, except for PostgreSQL which will remain on host machine.
I installed Docker, rise up container, but my app inside docker cannot connect to PostgreSQL database with default settings (localhost).
Here is my application.properties file:
spring.datasource.driverClassName=org.postgresql.Driver
spring.datasource.url=jdbc:postgresql://localhost:5432/webdemodb
spring.datasource.username=postgres
spring.datasource.password=123
spring.jpa.database-platform=org.hibernate.dialect.PostgreSQL95Dialect
spring.jpa.generate-ddl=true
Here is my Dockerfile:
FROM java:8
WORKDIR /
ADD target/webaccount-1.0-SNAPSHOT.jar app.jar
EXPOSE 8080
RUN fc-cache -f -v
ENTRYPOINT ["java","-jar","/app.jar"]
I read about Docker's networking but didn't find solution. What i need to setup?
Artemiy, thanks! For simple usage i've just applied the next option when running container:
--network="host"
Full command:
docker run -d -p 9000:8080 --network="host" --name webaccount webaccount:1.0
Related
I am working on golang project, recently I read about docker and try to use docker with my app. I am using mongoDB for database.
Now problem is that, I am creating Dockerfile to install all packages and compile and run the go project.
I am running mongo data as locally, if I am running go program without docker it gives me output, but if I am using docker for same project (just installing dependencies with this and running project), it compile successfully but not gives any output, having error::
CreateSession: no reachable servers
my Dockerfile::
# Start from a Debian image with the latest version of Go installed
# and a workspace (GOPATH) configured at /go.
FROM golang
WORKDIR $GOPATH/src/myapp
# Copy the local package files to the container's workspace.
ADD . /go/src/myapp
#Install dependencies
RUN go get ./...
# Build the installation command inside the container.
RUN go install myapp
# Run the outyet command by default when the container starts.
ENTRYPOINT /go/bin/myapp
# Document that the service listens on port 8080.
EXPOSE 8080
EXPOSE 27017
When you run your application inside Docker, it's running in a virtual environment; It's just like another computer but everything is virtual, including the network.
To connect your container to the host, Docker gives it an special ip address and give this ip an url with the value host.docker.internal.
So, assuming that mongo is running with binding on every interface on the host machine, from the container it could be reached with the connection string:
mongodb://host.docker.internal:21017/database
Simplifying, Just use host.docker.internal as your mongodb hostname.
In your golang project, how do you specify connection to mongodb? localhost:27017?
If you are using localhost in your code, your docker container will be the localhost and since you don't have mongodb in the same container, you'll get the error.
If you are starting your docker with command line docker run ... add --network="host". If you are using docker-compose, add network_mode: "host"
Ideally you would setup mongodo in it's own container and connect them from your docker-compose.yml -- but that's not what you are asking for. So, I won't go into that.
In future questions, please include relevant Dockerfile, docker-compose.yml to the extent possible. It will help us give more specific answer.
I'm having docker container up and running by using the following command:
docker run -p 27017:27017 -d mongo
Docker Logs for reference.
Then I clone a github repo: https://github.com/springframeworkguru/spring-boot-mongodb.git
Import the project in IntelliJ IDE, build it and run.
SpringBoot App Error Logs here
Issue : I'm not able to connect to the mongo app running in the container from my SpringBoot application as I'm getting MongoSocketOpenException as shown in the logs.
Any help is appreciated?
Docker version 18.03.0-ce, build 0520e24302
OS: Windows 10
Docker for win has some problems with loopback interfaces.
https://blog.sixeyed.com/published-ports-on-windows-containers-dont-do-loopback/
Try run docker inspect and configure your application with the container address.
Problem: I was trying to configure SpringBoot Application to mongo container IP which I retrieved from mongo inspect <mongo_container> command which was incorrect.
Solution: Configured my application using docker IP retrieved by docker-machine <env> which resolved the problem.
Link to the post is here.
I have created a web application in asp core but I do not understand how to link my database to my container.
I read that I need to compose two container but I did not find how to do that and how apply my migrations
Does someone can help me?? thanks guys.
here my Dockerfile
FROM microsoft/dotnet:latest
COPY . /app
WORKDIR /app
RUN dotnet restore
RUN dotnet build
EXPOSE 5000/tcp
ENV ASPNETCORE_URLS http://*:5000
ENV ASPNETCORE_ENVIRONMENT docker
ENTRYPOINT dotnet run
To allow communication between containers you can use link below is the example
Run postgres container
docker run --name mypostgres -d postgres
link the container to the web application
docker run --name webapp_name --link mypostgres:postgres -p 1001:80 -d webapp
I have this (custom) container which runs a java program which requires mongo locally. Now, with docker I would like to setup mongo in its own container. So I guess, in order to expose this 27017 port locally in this java-container I need to setup an SSH-tunnel, right ? If there is a easier way please let me know.
So, there is this official mongo image image, but I get the impression ssh is not install or running. What would be the best approach to do this?
UPDATE: I've rephrased the question more focussed on port-forwarding here
You have to make your container run on the same network. No need to ssh into your mongo or app container.
https://docs.docker.com/engine/userguide/networking/
First define a network
docker network create --driver bridge isolated_nw
Start you containers using that newly network
docker run -p 27017:27017 --network=isolated_nw -itd --name=mongo-cont mongo
docker run --network=isolated_nw -itd --name=app your_image
The image of mongo includes EXPOSE 27017 so from your app container, you should be able to access to the mongo container using its name mongo-cont
You can build your custom image on top of mongodb official image, which gives you the flexibility to install additional required packages.
FROM mongo:latest
RUN apt-get install ssh
Also try to use docker-compose to build and link your containers together, it will ease the process greatly.
version: '2'
services:
mongo:
image: mongo:latest
ports:
- "27017"
custom_project:
build:
context: . # Parent directory address of Dockerfile
dockerfile: Dockerfile-Custom # Name of Dockerfile
command: /root/docker-entrypoint.sh
This is the image used for mongodb official image.
You are trying to SSH into your container to gain access to it, but that isn't how you connect. Docker provides functionality to securely connect via the following methods.
Connect into a running container - Docs:
docker exec -it <container name> bash
$ root#665b4a1e17b6:/#
Start a container from image, and connect to it - Docs:
docker run -it <image name> bash
$ root#665b4a1e17b6:/#
Note: If it is an Alpine based image, it may not have Bash installed. In that case using sh instead of bash in your commands should work. Mongo's Dockerfile looks to use debian:jessie which will have bash support.
I think I don't get it. First, I created docker-machine:
$ docker-machine create -d virtualbox dev
$ eval $(docker-machine env dev)
Then I wrote Dockerfile and docker-compose.yml:
FROM python:2.7
ENV PYTHONUNBUFFERED 1
RUN mkdir /code
WORKDIR /code
ADD requirements.txt /code/
RUN pip install -r requirements.txt
ADD . /code/
version: '2'
services:
db:
image: postgres
web:
build: .
restart: always
command: python manage.py runserver 0.0.0.0:8000
volumes:
- .:/code
ports:
- "8000:8000"
links:
- db
Finally, I built and started the image:
$ docker-compose build --no-cache
$ docker-compose start
I checked ip of my virtual machine
$ docker-machine ip dev
and successfully opened the site in my browser. But when I made some changes in my code - nothing happened. So I logged to the "dev" machine:
$ docker-machine ssh dev
and I didn't find my code! So I logged to the docker "web" image:
$ docker exec -it project_web_1 bash
and there was a code, but unchanged.
What is the docker-machine for? What is the sense? Why docker doesn't syncing files after changes? It looks like docker + docker-machine + docker-compose are pain in the a...s for local development :-)
Thanks.
Docker is the command-line tool that uses containerization to manage multiple images and containers and volumes and such -- a container is basically a lightweight virtual machine. See https://docs.docker.com/ for extensive documentation.
Until recently Docker didn't run on native Mac or Windows OS, so another tool was created, Docker-Machine, which creates a virtual machine (using yet another tool, e.g. Oracle VirtualBox), runs Docker on that VM, and helps coordinate between the host OS and the Docker VM.
Since Docker isn't running on your actual host OS, docker-machine needs to deal with IP addresses and ports and volumes and such. And its settings are saved in environment variables, which means you have to run commands like this every time you open a new shell:
eval $(docker-machine env default)
docker-machine ip default
Docker-Compose is essentially a higher-level scripting interface on top of Docker itself, making it easier (ostensibly) to manage launching several containers simultaneously. Its config file (docker-compose.yml) is confusing since some of its settings are passed down to the lower-level docker process, and some are used only at the higher level.
I agree that it's a mess; my advice is to start with a single Dockerfile and get it running either with docker-machine or with the new beta native Mac/Windows Docker, and ignore docker-compose until you feel more comfortable with the lower-level tools.