First of all, I'm sorry for my English.
I am developing an ASP.NET Core Web API, and I am working with a friend. To work together comfortably I wanted to set up a Docker with our API, and a database running. And I have problem with Entity Framework.
Here is the problem, the name of the container for Postgres is postgres_image, so the connection string to connect to it from the api is:
"Host=postgres_image;Port=5432;Database=grdedb;Username=postgres;Password=postgres"
And it is working. But when I want to create an Entity Framework migration to the database located in the Docker container, it doesn't work; I have to change the host to localhost.
But when I change it the migration works and after that it is the API which stops.
Thank you very much for your help
My docker compose file
version: '3.4'
networks:
grdeapi-dev:
driver: bridge
services:
grdeapi:
image: grdeapi
build:
context: .
dockerfile: ./Dockerfile
ports:
- 5101:5101
networks:
- grdeapi-dev
postgres_image:
image: postgres:latest
ports:
- 5432:5432
restart: always
volumes:
- db_volume:/var/lib/postgresql/data
environment:
POSTGRES_USER: "postgres"
POSTGRES_PASSWORD: "postgres"
POSTGRES_DB: "grdedb"
networks:
- grdeapi-dev
volumes:
db_volume:
My connection string
"Host=postgres_image;Port=5432;Database=grdedb;Username=postgres;Password=postgres"
And the error I get from the entity framework
Failed to connect to 212.95.74.75:5432
Entity framework works when I change the host to localhost, but then my dotnet api can't connect to my database.
Have a config for running in Docker, and one for running in development.
In the former (name it appsettings.Development.Docker.json for example) configure your connection string with the Docker hostname ("postgres_image"), and locally (when running from Visual Studio or when running migrations against said database server) just use "localhost". Name the latter appsettings.Development.json.
Then adjust your DOTNET_ENVIRONMENT accordingly:
services:
grdeapi:
DOTNET_ENVIRONMENT: "Development.Docker"
Related
I'm set up docker compose for my project with 2 services: spring-boot and postgresql. I created Dockerfile and docker-compose,yml as below:
Dockerfile :
FROM openjdk:8-jdk-alpine
MAINTAINER linhan.com
COPY target/LinhAn-0.0.1-SNAPSHOT.jar linhan-server-1.0.0.jar
ENTRYPOINT ["java","-jar","/linhan-server-1.0.0.jar"]
docker-compose.yml:
version: '2'
services:
spring_boot:
image: 'linhan'
build: .
container_name: api
ports:
- "8080:8080"
depends_on:
- postgres
environment:
- SPRING_DATASOURCE_URL=jdbc:jdbc:postgresql://localhost:5432/test_db
- SPRING_DATASOURCE_USERNAME=user
- SPRING_DATASOURCE_PASSWORD=123456
- SPRING_JPA_HIBERNATE_DDL_AUTO=update
postgres:
image: 'postgres:13.1-alpine'
container_name: db
environment:
- POSTGRES_USER=user
- POSTGRES_PASSWORD=123456
Then, when I type docker-compose up in terminal, postgres ran only, spring boot still not.
I searched google for solution but seems no hope. Please help me, thanks a lot!!!!!
I think you need to change the SPRING_DATASOURCE_URL to reference your service name instead of localhost. The service name is resolved automatically to your service since all services are part of the default_network by default in docker-compose.
- SPRING_DATASOURCE_URL=jdbc:jdbc:postgresql://postgres:5432/test_db
Also, for clarity I would suggest you add the port to your docker-compose postgres service, so it is clear which port is being used, even if it is the default:
postgres:
image: 'postgres:13.1-alpine'
container_name: db
ports:
- "5432"
environment:
- POSTGRES_USER=user
- POSTGRES_PASSWORD=123456
Also, another suggestion would be to try and use a healthcheck to see if your database service becomes available instead of a simple depends_on. The short version will mark the dependency fulfilled as soon as the container is Running, regardless of the availability of the database.
Either that, or you can add application logic to retry database connection in case of failure.
Warning: I am fairly new to docker and cloud hosting, this is likely a dumb question.
I have a local web app which has 3 images associated with it, the app itself, the db and a phpmyadmin image. All works well locally, and if I transfer all the files to my digital ocean droplet and bring up my containers it works fine there as well, but this is not how I want to deploy having every file from every library residing in my droplet.
I have been experimenting with creating a docker-machine on my droplet and deploying my containers remotely to it. This seems to work fine other than the fact that my db image does not reference my database and is simply an empty db. I tried to migrate the db in this fashion which I saw in a tutorial:
docker-compose run --rm web db:create db:migrate
But got the following error, I assume this is because my dev machine is running Windows 10 not Linux, but I cannot find anywhere what the equivalent command would be for a Windows machine.
Error response from daemon: OCI runtime create failed: container_linux.go:346: starting container process caused "exec: \"db:create\": executable file not found in $PATH": unknown
I know I am probably missing something really stupid and easy but I am having difficulties figuring out how to migrate the data for my db image. Thanks in advance.
UPDATE:
As requested here is my docker-compose:
version: "3.4"
services:
phpmyadmin:
image: phpmyadmin/phpmyadmin
environment:
- PMA_ARBITRARY=1
- PMA_HOST=db
restart: always
ports:
- 80:80
volumes:
- /sessions
depends_on:
- db
db:
image: mysql:latest
environment:
MYSQL_ROOT_PASSWORD: mypass
MYSQL_DATABASE: mydb
ports:
- "3306:3306"
volumes:
- ./data:/docker-entrypoint-initdb.d
restart: always
web:
depends_on:
- db
build: .
ports:
- "8080:8080"
restart: always
volumes:
data:
UPDATE #2:
transfered db file to /docker-entrypoint-initdb.d (I tried this yesterday too but couldn't get it working) and created a new production docker-compose-prod.yml I must be missing something still though as the DB is still empty. Below is my new docker-compose-prod.yml:
version: "3.4"
services:
phpmyadmin:
image: phpmyadmin/phpmyadmin
environment:
- PMA_ARBITRARY=1
- PMA_HOST=db
restart: always
ports:
- 80:80
volumes:
- /sessions
depends_on:
- db
db:
image: mysql:latest
environment:
MYSQL_ROOT_PASSWORD: mypass
MYSQL_DATABASE: mydb
ports:
- "3306:3306"
volumes:
- /docker-entrypoint-initdb.d
restart: always
web:
depends_on:
- db
build: .
ports:
- "8080:8080"
restart: always
Your strategy is sound.
Actually, you can take it a further step by automating the Droplet provisioning to e.g. use a container-oriented OS and access your Compose file. But that's not this question ;-)
I think it is not relevant that you're using Windows and probably makes little difference; it may require some answer tweaks but that's about it.
The challenge is that you need to move (or recreate) the database state on the remote machine. There are several ways that the DB state could be persisted: in-container (not ideal); using volume mounts (good), other.
Each is "moveable" but it would help if you could add your Compose file to your question so that we may see which approach is being used.
In full-disclosure Im not familiar with the approach that you referencesd but that does not mean that it's inaccurate; I'm just not familiar with it.
Update: docker-entrypoint-initdb.d
See: "Initializing a fresh instance" on MySQL
So, any files within that directory are run to initialize the database container when it's created from the image.
In your Compose file you mount your host's ./data directory into this file. Presumably that directory contains >=1 file that performs your intended initialization.
NB The section volumes: data: at the end of the Compose file appears redundant. You're actually using a host-mounted directory ./data not this volume.
When you run the Compose file on the Droplet, those files aren't present and you'll need to copy them.
The simplest way to do this is to use scp and this provides 2 alternatives:
Either retain the data directory:
IP=[DROPLET-IP]
scp -r ./data root#${IP}:/data
NB The remote destination is /data not ./data. You will need to revise the Compose file on the Droplet (!) too:volumes: - /data:/docker-entrypoint-initdb.d
Or move the files directly to the Droplet's /docker-entrypoint-initdb.d:
scp -r ./data root#${IP}/docker-entrypointy-initdb.d
NB Now there's no need for the volume mapping. You may remove: volumes: - ./data:/docker-entrypoint-initdb.d
Update: repro (works)
I used a tweaked docker-compose.yaml but it's essentially the same:
version: "3.4"
services:
db:
image: mysql:latest
environment:
MYSQL_ROOT_PASSWORD: mypass
MYSQL_DATABASE: mydb
ports:
- "3306:3306"
volumes:
- ${PWD}/docker-entrypoint-initdb.d:/docker-entrypoint-initdb.d
restart: always
adminer:
image: adminer
restart: always
ports:
- 8080:8080
Then mkdir ${PWD}/docker-entrypoint-initdb.d and created a file in it called freddie.sql:
create database if not exists frederik;
use frederik;
create table treats (
TreatID INT NOT NULL AUTO_INCREMENT,
TreatName VARCHAR(255) NOT NULL,
PRIMARY KEY (TreatId));
insert into treats (TreatName)
values
("Dried Salmon"),
("Meatballs");
Then docker-compose rm --force && docker-compose up
I was able to browse the adminer UI (:8080), login (root|mypass) and browse the database frederik:
I'm having trouble accessing a database created from a docker-compose file.
Given the following compose file, I should be able to connect to it from java using something like:
jdbc:postgresql://eprase:eprase#database:7000/eprase
However, the connection is rejected. I can't even use PGAdmin to connect it using the same details to create a new server.
I've entered the database container and ran psql commands to verify that the eprase user and database have been created according to postgres Docker documentation, everything seems fine. I can't tell if the problem is within the database container or something I need to change in the compose network.
The client & server services can largely be ignored, the server is a java based web API and the client is an Angular app.
Compose file:
version: "3"
services:
client:
image: eprase/client:latest
build: ./client/eprase-app
networks:
api:
ports:
- "5000:80"
tty: true
depends_on:
- server
server:
image: eprase/server:latest
build: ./server
networks:
api:
ports:
- "6000:8080"
depends_on:
- database
database:
image: postgres:9
volumes:
- "./database/data:/var/lib/postgresql/data"
environment:
- "POSTGRES_USER=eprase"
- "POSTGRES_PASSWORD=eprase"
- "POSTGRES_DB=eprase"
networks:
api:
ports:
- "7000:5432"
restart: unless-stopped
pgadmin:
image: dpage/pgadmin4:latest
environment:
- "PGADMIN_DEFAULT_EMAIL=admin#eprase.com"
- "PGADMIN_DEFAULT_PASSWORD=eprase"
networks:
api:
ports:
- "8000:80"
depends_on:
- database
networks:
api:
The PostgreSQL database is listening on container port 5432. The 7000:5432 line is mapping host port 7000 to container port 5432. That allows you to connect to the database on port 7000. But, your services on a common network (api) should communicate with each other via the container ports.
So, from the perspective of the containers for the client and server services, the connection string should be:
jdbc:postgresql://eprase:eprase#database:5432/eprase
I am currently trying to use Docker for my new Django/Postgres project. I am working on a Mac and usually use Postico to quickly connect to my database.
I used to connect like here:
I used the official Docker documentation to setup docker-compose. I now have the issue, that I can't connect via Postico to the postgres db. It seems to me that the problem comes from the ports not being exposed.
version: '3'
services:
db:
image: postgres
web:
build: .
command: python3 manage.py runserver 0.0.0.0:8000
volumes:
- .:/code
ports:
- "8000:8000"
depends_on:
- db
Just map the port to the host machine, add this to the db service in your Compose file:
ports:
- "5432:5432"
Also make sure to set the postgres password variable in the compose file like this
environment:
POSTGRES_PASSWORD: example
The default user is postgres, you can change it with the POSTGRES_USER variable.
You can read about the usage of the image with all options here: https://hub.docker.com/_/postgres/
By default Compose sets up a single network for your app.
Each container can be accessed by the name of the service in the compose file.
In your case you don't have to expose the port to the host machine for your web app to have access to it. You can simply use db as the hostname for postgres (and 5432 for the port) from any other service running on the same compose.
Actually a very similar example is provided in the docker compose documentation:
https://docs.docker.com/compose/networking/
I'm working into a Docker container for some study, using nginx + php + postrgresql, and some ssh to connect with host.
Problem is that I can't exchange the container's PostgreSQL admin password (for internal, not filesystem).
I've based my Dockerfile into some I've investigated and looked like what I wanted.
The Dockerfile is here
Either tried with lines 84-85 and using the same lines at an script called at lines 80-82. Either option, I receive the same error message:
psql: 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"?
It's not the answer you're looking for but ideally you would run your database in a separate container and have the app container running httpd and your php code linked to it using docker-compose. The official postgres image exposes an env var to set the admin password, POSTGRES_PASSWORD.
I've found that using official images for things like databases saves alot of time and headache as the teams producing them add easy-to-use features to get you off the ground quickly, such as env vars to set db passwords.
The docker team has a good tutorial for wordpress using mysql that should point you in the right direction regarding a docker-compose file https://docs.docker.com/compose/wordpress/
version: '2'
services:
db:
image: mysql:5.7
volumes:
- db_data:/var/lib/mysql
restart: always
environment:
MYSQL_ROOT_PASSWORD: somewordpress
MYSQL_DATABASE: wordpress
MYSQL_USER: wordpress
MYSQL_PASSWORD: wordpress
wordpress:
depends_on:
- db
image: wordpress:latest
ports:
- "8000:80"
restart: always
environment:
WORDPRESS_DB_HOST: db:3306
WORDPRESS_DB_USER: wordpress
WORDPRESS_DB_PASSWORD: wordpress
volumes:
db_data: