I'd like to create a docker image with data.
My attempt is as follows:
FROM postgres
COPY dump_testdb /image
RUN pg_restore /image
RUN rm -rf /image
Then I run docker build -t testdb . and docker run -d testdb.
When I connect to the container I don't see the restored db. How do I get an image with the restored data?
COPY the dump file, with a .sql extension, into /docker-entrypoint-initdb.d/. Do not try to RUN anything. The postgres image will run everything in that directory the first time a container is started on a particular data directory.
You generally can’t RUN commands that interact with the database in a Dockerfile because the database won’t be running at that point. (There is a script in the base image that goes through some complicated gymnastics to do the first-time setup.) In any case, because of the mechanics of Docker’s volume system, you can’t create an image that contains prepopulated database data; you have to use a mechanism like this to cause the image to restore a dump or otherwise set itself up at first start.
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I have my Gitlab CI running with Symfony, I have fixtures loaded and I want to load them in a buffer dabatase, and then to move them to the real database.
I've seen this thread: Docker - How can run the psql command in the postgres container?, but I would like to have an automatic script which:
delete my real database
rename my buffer database to the real database's name
Is it possible using Docker & Gitlab CI to automate such commands? I am using pg_dump for now, but it's long an not easy to use, I just want to replace a DB with an other DB.
Has someone solved the postgre database auto import when creating a docker image? The traditional method is to put files into the docker-entrypoint-initdb.d. But, it does not work for me, because I need to import via pg_restore (because of custom-format dump). I do not know how to start postgres service through dockerfile. The problem is that every time it runs in a separate container layer. Thank you for your help.
I solved this by put .sh script(which contains pg_restore commands) to docker-entrypoint-inidb.d. I use official Postgre image, which runs after dockerfile any .sql and .sh files, which are in docker-entrypoint-initdb.d
More info https://github.com/docker-library/docs/tree/master/postgres#how-to-extend-this-image
Till now I've been backing up my postgresql data using pg_dump, which exports the data to an sql file mydb.sql, and then restoring from that sql file using psql -U user -d db < mydb.sql.
For one reason or another it would be more convenient to restore the database content more directly, in an environment where psql does not exist... specifically on a host server where postgresql is installed in a docker container running on the host, but not on the host itself.
My plan is to back up the content of /var/lib/postgresql/data/ to a tar file, and when required (e.g. when a new server is created that hosts the postgresql container) just restore that to the same path. The folder /var/lib/postgresql/data/ in the docker container is mapped to a folder on the host server, so I would create this backup on the host, not inside the postgres container.
Is this a valid approach? Any "gotchas"? And are there any subfolders within /var/lib/postgresql/data/ that I can exclude from the tar file? I don't want to back up mere 'housekeeping' information.
You can do that, but you have to do it properly if you don't want your database to become corrupted.
Either stop PostgreSQL before copying the data directory or follow the instructions from the documentation for an online backup.
i am trying to run my Postgis Database in a Docker Container. Therefore i dumped my database and created a Dockerfile like this:
FROM mdillon/postgis
COPY z_myDump.sql /docker-entrypoint-initdb.d/
I use the mdillon postgis as base image (Postgis Extensions are already included) and copy my dump. The container disappears after a few seconds with the following error:
/usr/local/bin/docker-entrypoint.sh: running /docker-entrypoint-initdb.d/z_myDump.sql
/docker-entrypoint-initdb.d/z_myDump.sql: Permission denied
any idea?
changing permissions of the .sql file before building the image did the job ... my bad
I've created docker image with PostgreSQL running inside and exposing 5432 port.
This image doesn't contain any database inside. Container is an empty PostgreSQL database server.
I'd like in (or during) "docker run" command:
attach db file
create db via sql query execution
restore db from dump
I don't want to keep the data after container will be closed. It's just a temporary development server.
I suspect it's possible to keep my "docker run" command string quite short/simple.
Probably there it is possible to mount some external folder with db/sql/dump in run command and then create db during container initialization.
What are the best/recommended way and the best practices to accomplish this task? Probably somebody can point me to corresponding docker examples.
This is a good question and probably something other folks asked themselves more than once.
According to the docker guide you would not do this in a RUN command. Instead you would create yourself an ENTRYPOINT or CMD in your Dockerfile that calls a custom shell script instead of calling the postgres process direclty. In this scenario the DB would be created in a "real" filesystem, but then cleaned-up during shutdown of the container.
How would this work? The container would start, call the ENTRYPOINT or CMD as usual and consume the init script to get the DB filled. Then at the moment the container is stopped, the same script will be notified with a signal and manually drop the database content.
CMD ["cleanAndRun.sh"]
A sketched script "cleanAndRun.sh" taken from the Docker documentation and modified for your needs. Please remember it is a sketch only and needs modifications:
#!/bin/sh
# The script that is called in the trap must also stop the DB, so below call to
# dropdb is not enough, it just demonstrates how to call anything in the stop-container scenario!
trap "dropdb <params>" HUP INT QUIT TERM
# init your DB -every- time container starts
<init script to import to clean and import dump>
# start your postgres DB
postgres
echo "exited $0"