Docker

為什麼我的容器在我送出後不包含數據庫數據?

  • July 2, 2021

我正在嘗試創建一個已經包含開發數據的 PostgreSQL 容器。我可以看到我創建的數據,但是當我commit、、pushpull圖像時,數據不存在。

下面是我的 Dockerfile:

FROM postgis/postgis:11-2.5
MAINTAINER Me

# Contents of 20-init_db.sql:
# CREATE EXTENSION IF NOT EXISTS btree_gist;
# CREATE EXTENSION IF NOT EXISTS hstore;
COPY ./20-init_db.sql /docker-entrypoint-initdb.d/20-init_db.sql
COPY ./make_data.sh /make_data.sh

我使用下面的腳本創建了容器,並且成功填充了數據。

#!/bin/bash

aws ecr get-login-password --region us-east-1 | \
   docker login --username AWS --password-stdin 23456789JQKA.dkr.ecr.us-east-1.amazonaws.com

aws ecr create-repository --repository-name dev_postgres --region us-east-1

# Make sure the build environment is clean
docker stop dev_postgres_container
docker rm dev_postgres_container
docker rmi dev_postgres_img

# Prepare the container
docker build -f postgres.Dockerfile -t dev_postgres_img .
docker run -d --name dev_postgres_container \
   -e POSTGRES_DB=the_database \
   -e POSTGRES_USER=the_user \
   -e POSTGRES_PASSWORD=the_password \
   -e PGDATA=/var/lib/postgresql/data/pgdata
   dev_postgres_img
docker exec -it dev_postgres_container bash /make_data.sh

###
### This returns the correct number of users, so there is data in the container at this point.
###
docker exec -it dev_postgres_container /usr/bin/psql -U the_user the_database -c "select count(*) from auth_user;"

# Commit the container state and save it to Amazon ECR:
docker commit $(docker ps -q --filter "name=dev_postgres_container") 23456789JQKA.dkr.ecr.us-east-1.amazonaws.com/dev_postgres:11-2.5-with-data

# Also tag it with "latest" and the timestamp
docker tag 23456789JQKA.dkr.ecr.us-east-1.amazonaws.com/dev_postgres:11-2.5-with-data 23456789JQKA.dkr.ecr.us-east-1.amazonaws.com/dev_postgres:latest-with-data
docker tag 23456789JQKA.dkr.ecr.us-east-1.amazonaws.com/dev_postgres:11-2.5-with-data 23456789JQKA.dkr.ecr.us-east-1.amazonaws.com/dev_postgres:$( date -u +%Y%m%d_%H%MZ )-with-data

# Push
docker push 23456789JQKA.dkr.ecr.us-east-1.amazonaws.com/dev_postgres --all-tags

但是,當我在隔離環境中拉容器時,沒有數據:

brew install virtualbox
brew install multipass
sudo multipass set local.driver=virtualbox
multipass launch --name ubuntu2
multipass mount ~/.aws ubuntu2:/home/ubuntu/.aws
multipass mount ./db ubuntu2:/home/ubuntu/db
multipass exec ubuntu2 -- bash /home/ubuntu/db/test_db_container.sh

### Contents of test_db_container.sh are below: ###

curl -fsSL https://get.docker.com -o get-docker.sh
sudo sh get-docker.sh

sudo apt-get install -y awscli

# Pull Docker container:
aws ecr get-login-password --region us-east-1 | \
   sudo docker login --username AWS --password-stdin 23456789JQKA.dkr.ecr.us-east-1.amazonaws.com
sudo docker pull 23456789JQKA.dkr.ecr.us-east-1.amazonaws.com/dev_postgres:latest-with-data

sudo docker run -d --name the_db 23456789JQKA.dkr.ecr.us-east-1.amazonaws.com/dev_postgres:latest-with-data

###
### The auth_user table does not exist.
###
sudo docker exec -it the_db /usr/bin/psql -U the_user the_database -c "select count(*) from auth_user;"

sudo docker history 23456789JQKA.dkr.ecr.us-east-1.amazonaws.com/dev_postgres:latest-with-data

## Result:
IMAGE          CREATED        CREATED BY                                      SIZE      COMMENT
854dbef239c2   23 hours ago   postgres                                        70B
4b1bd66a8d33   23 hours ago   COPY ./make_data.sh /make_data.sh               3.03kB    buildkit.dockerfile.v0
<missing>      23 hours ago   COPY ./20-init_db.sql /docker-entrypoint-ini…   188B      buildkit.dockerfile.v0
<missing>      23 hours ago   MAINTAINER Me                                   0B        buildkit.dockerfile.v0
[...]

旁注:我考慮過創建一個數據卷容器,但這種方法似乎更簡單且文件更好。

其他注意事項:我無法在 Dockerfile 中添加數據,因為 Postgres 需要在插入數據之前執行。

為什麼不docker commit保存我的容器的狀態?為什麼圖像不包含數據?

根據主執行緒下的評論,該解決方案類似於此現有答案中建議的解決方案。它歸結為數據目錄是一個卷,因此位於被修改/送出的容器的上下文之外。

引用自:https://serverfault.com/questions/1068085