I'm new to docker and am trying to make a composed image consisting of services, nginx and postgresql database. I'm following the tutorial here : http://www.patricksoftwareblog.com/how-to-use-docker-and-docker-compose-to-create-a-flask-application/
And have been successful up to adding postgresql where I'm having difficulties and questions.
My docker-compose.yml:
version : '2'
services:
web:
restart: always
build: ./home/admin/
expose:
- "8000"
nginx:
restart: always
build: ./etc/nginx
ports:
- "80:80"
volumes:
- /www/static
volumes_from:
- web
depends_on:
- web
data:
image: postgres:9.6
volumes:
- /var/lib/postgresql
command: "true"
postgres:
restart: always
build: ./var/lib/postgresql
volumes_from:
- data
ports:
- "5432:5432"
I have included his docker generator script under /var/lib/postgresql but keep facing ERROR: Dockerfile parse error line 1: unknown instruction: IMPORT when I run 'docker-compose build'.
If I leave in the 'data' section & remove the postgres section in my docker-compose.yml file, my containers seemingly run fine but I'm unsure if postgresql is properly running at all. I'm able to GET using curl but still - I'm unsure how to go about confirming postgres specifics to confirm a proper environment and would appreciate examples on this topic in particular.
I was also wondering if running my docker-compose containers then simply running a separate postgresql container could also function if provided the correct ports.
Thank you!
Check the content of your docker-compose.yml:
yaml format (see for instance codebeautify.org/yaml-validator)
eol or encoding issue
multi-line instructions
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 would like to be able to deploy my app in a pre-prod environment for integration testing using a Docker volume that will expose an instance of PostgreSQL. I'm using Scala v2.12.8 and Play v2.7.
Looking at the environment settings of the SBT native packager it seems possible to define dockerExposedVolumes in order to attach a DB.
Using a normal Docker compose file I would do something like that:
version: "3"
services:
db:
image: postgres
environment:
- POSTGRES_USER=postgres
- POSTGRES_PASSWORD=postgress
- POSTGRES_DB=postgres
ports:
- "5433:5432"
volumes:
- pgdata:/var/lib/postgresql/data
networks:
- suruse
volumes:
pgdata:
This configuration has been taken from this SO answer.
I tried searching for config examples but I didn't find anything useful so far. Now I'm wondering how I should define a new docker volume and then expose it to the Docker image created by SBT exactly?
THE WORKING SOLUTION
The final version. I've fully tested it and it works exposing the DB on the TCP port 5433.
# https://docs.docker.com/samples/library/postgres/
version: "3"
services:
app-pgsql:
image: postgres:9.6
restart: always
environment:
- POSTGRES_USER=postgres
- POSTGRES_PASSWORD=yourPasswordHere
- POSTGRES_DB=yourDatabaseNameHere
- POSTGRES_INITDB_ARGS="--encoding=UTF8"
ports:
- "5433:5432"
volumes:
- pgdata:/var/lib/postgresql/data
volumes:
pgdata:
driver: local
Launch the docker compose using sbt dockerComposeUp -useStaticPorts and then check if the containers have been actually exposed using docker ps -a. Also, check the log files using the command provided by dockerComposeUp or dockerComposeInstances.
There is a sbt Plugin that helps you to achieve this:
sbt-docker-compose
With that you can add your database to a docker compose file and you can run everything within sbt.
This is a Docker standard. Here is an explaination how to do it for Postgres:
[run_postgresql_docker_compose][2]
The docker-compose.yml from that example:
version: '3'
services:
mydb:
image: postgres
volumes:
- db-data:/var/lib/postgresql/data
ports:
- 5432:5432/tc
volumes:
db-data:
driver: local
As this is a standard way of Docker you will find more examples.
So i currently can use "docker-compose up test" which only runs my database and my testing scripts. I want to be able to us say docker-compose up app" or something like that that runs everything besides testing. That way Im not running unnecessary containers. Im not sure if theres a way but thats what I was wondering. If possible Id appreciate some links to some that already do that and I can figure out the rest. Basically can I only run certain containers with a single command without running the others.
Yaml
version: '3'
services:
webapp:
build: ./literate-app
command: nodemon -e vue,js,css start.js
depends_on:
- postgres
links:
- postgres
environment:
- DB_HOST=postgres
ports:
- "3000:3000"
networks:
- literate-net
server:
build: ./readability-server
command: nodemon -L --inspect=0.0.0.0:5555 server.js
networks:
- literate-net
redis_db:
image: redis:alpine
networks:
- literate-net
postgres:
restart: 'always'
#image: 'bitnami/postgresql:latest'
volumes:
- /bitnami
ports:
- "5432:5432"
networks:
- literate-net
environment:
- "FILLA_DB_USER=my_user"
- "FILLA_DB_PASSWORD=password123"
- "FILLA_DB_DATABASE=my_database"
- "POSTGRES_PASSWORD=password123"
build: './database-creation'
test:
image: node:latest
build: ./test
working_dir: /literate-app/test
volumes:
- .:/literate-app
command:
npm run mocha
networks:
- literate-net
depends_on:
- postgres
environment:
- DB_HOST=postgres
networks:
literate-net:
driver: bridge
I can run docker-compose up test
Which only runs the postgres. Though I'd like to be able to just run my app without having to run my testing container.
Edit
Thanks to #ideam for the link
I was able to create an additional yaml file for just testing.
For those that dont want to look it up simply create a new yaml file like so
docker-compose.dev.yml
replace dev with whatever you like besides override which causes docker-compose up to automatically run that unless otherwise specified
To run the new file simply call
docker-compose -f docker-compose.dev.yml up
The -f is a flag for selecting a certain file to run. You can run multiple files to have different enviornments set-up
Appreciate the help
docker-compose up <service_name> will start only the service you have specified and its dependencies. (those specified in the dependends_on option.)
you may also define multiple services in the docker-compose up command:
docker-compose up <service_name> <service_name>
note - what does it mean "start the service and its dependecies"?
usually your production services (containers) are attached to each other via the dependes_on chain, therefore you can start only the last containers of the chain. for example, take the following compose file:
version: '3.7'
services:
frontend:
image: efrat19/vuejs
ports:
- "80:8080"
depends_on:
- backend
backend:
image: nginx:alpine
depends_on:
- fpm
fpm:
image: php:7.2
testing:
image: hze∂ƒxhbd
depends_on:
- frontend
all the services are chained in the depends_on option, while the testing container is down bellow the frontend. so when you hit docker-compose up frontend docker will run the fpm first, then the backend, then the frontend, and it will ignore the testing container, which is not required for running the frontend.
Starting with docker-compose 1.28.0 the new service profiles are just made for that! With profiles you can mark services to be only started in specific profiles:
services:
webapp:
# ...
server:
# ...
redis_db:
# ...
postgres:
# ...
test:
profiles: ["test"]
# ...
docker-compose up # start only your app services
docker-compose --profile test up # start app and test services
docker-compose run test # run test service
Maybe you want to share your docker-compose.yml for a better answer than this.
For reusing docker-compose configurations have a look at https://docs.docker.com/compose/extends/#example-use-case which explains the combination of multiple configuration files for reuse of configs for different use cases (test, production, etc.)
Here my simple scenario, I have a simple Flaskapp that connect to a postgres this way:
SQLALCHEMY_DATABASE_URI='postgresql://username:secretpassword#postgres:5432/myproj'
And I have a simple docker-compose.yml:
version: '2'
services:
postgres:
image: postgres:latest
volumes_from:
- data
environment:
POSTGRES_PASSWORD: secretpassword
POSTGRES_USER: username
POSTGRES_DB: myproj
ports:
- "5432:5432"
web:
build: .
volumes_from:
- app
ports:
- "5000:5000"
depends_on:
- postgres
data:
image: postgres:latest
volumes:
- /var/lib/postgresql/data
command: "true"
app:
build: .
volumes:
- .:/myproj
command: "true"
I need to lunch a made by myself flask script, that creates the tables for my app:
export FLASK_APP='./myproj/__init__.py'
flask createdbs
I have put these 2 operation in the Dockerfile of my web service but because my service and the postgres service have a depends_on relationship, the postgres db host is not available during the building phase.
Any suggestion on the best way to achieve this ? I want to avoid hacks, I would prefer respect a correct Docker workflow.
One way to do it is to use the "command" keyword:
https://docs.docker.com/compose/compose-file/#/command
(look also at entrypoint keyword)
web:
build: .
volumes_from:
- app
ports:
- "5000:5000"
depends_on:
- postgres
command: "export FLASK_APP='./myproj/__init__.py' && flask createdbs"
or using command just to launch your flask script and let your export in your dockerfile.
Note that "depends_on" only start one container before the other, but do not wait your postgres database to be ready. If you want to wait until postgres is ready to answer, you can use scripts like "wait-for-it.sh postgres:5432" that are well explained in docker-compose doc: https://docs.docker.com/compose/startup-order/