.sql file in Docker Postgres Container not automatically executed - postgresql

I have a .sql file created from a pg_dump command that I would like to have automatically inserted into my PostgreSQL instance in my Docker container. I mount my .sql file into the docker-entrypoint-initdb.ddirectory using volume. My Docker YML file looks like the following:
postgres:
environment:
- POSTGRES_USER=user
- POSTGRES_PASSWORD=pw
- POSTGRES_DB=db
volumes:
- ./out.sql:/docker-entrypoint-initdb.d/out.sql
image: "postgres:9.6"
Since the sql file has been mounted into docker-entrypoint-initdb.d I expect it to automatically run and insert my data when I run docker-compose -f myyml.yml up -d. It does not execute. However, when I run bash in my container I do see my .sql file. Also, I can manually run the file with a command similar to psql -U user -a -f out.sql. Why is it not automatically running when I run docker-compose?

So after a lot of trial and error, I realized that I needed to remove all images and containers and restart. I ran a docker-compose myyml.yml down and reran and it seemed to work.

i think you can add command in docker compose, and as following psql -U user -a -f out.sql
postgres:
environment:
- POSTGRES_USER=user
- POSTGRES_PASSWORD=pw
- POSTGRES_DB=db
volumes:
- ./out.sql:/docker-entrypoint-initdb.d/out.sql
image: "postgres:9.6"
command: bash -c "psql -U user -a -f out.sql"
note : if with use command bash -c is not work, remove it

Related

Docker Compose - Container Bash Forking

I am trying to run netbox based on their standard guide on Docker Hub with a slight difference that I need our existing postgres dump to be restored when the postgres container starts.
I have tried a few approaches like defining a command option in docker-compose file like (and a few more combinations):
sleep 2 && psql -U netbox -f netbox.sql
sleep is required to prevent psql command running before the postgres service is started.
Or defining a bash script that does the database restore but all these approaches cause the container to exit after that command/script is run.
My last resort was to utilize bash forking and this is what the postgres snippet of docker-compose looks like:
postgres:
image: postgres:13-alpine
env_file: env/postgres.env
command:
- sh
- -c
- (sleep 3 && cd /home && psql -U netbox -f netbox.sql) & su -c postgres postgres
volumes:
- ./my_db:/home/
- netbox-postgres-data:/var/lib/postgresql/data
Sadly this throws results in:
postgres: could not access the server configuration file
"/var/lib/postgresql/data/postgresql.conf": No such file or directory
If I omit the command section of docker-compose, the container starts up fine and I can navigate and ls the directory in the error message but it is not what I really need because this container will go on to be part of a much larger jungle of an ecosystem with little to no control over it afterwards.
Could it be my bash forking or the problem lies somewhere else?
Thanks in advance
I was able to find a solution by going through the thread that David Maze shared in the comments.
In my case, placing the *.sql file inside /docker-entrypoint-initdb.d did not work but I wrote a bash script, placed it in /docker-entrypoint-initdb.d directory and it got triggered.
The bash script was a very simple one, it would cd to the directory containing the sql dump and then restore it by running psql:
psql -U netbox -f netbox.sql

How to restore mongoDb collection BSON backup files to docker abernix/meteord:node-8.4.0-base?

I have made a backup from a mongoDb collection with the following command
mongodump -h 127.0.0.1 --port 9001 -d meteor -c products
I have copied the dump folder recursively to my server with the following command
scp -r dump root#66.204.148.25:/root
I can not restore with the following command
docker exec -i mongodb mongorestore -d mew -c audioQuestions_Joker dump/meteor
the files are there but I get the following message
2020-01-12T11:38:10.863+0000 Failed: mongorestore target 'dump/meteor' invalid: stat dump/meteor: no such file or directory
What would be the correct command to restore the collection backup from the BSON files?
FYI docker abernix/meteord:node-8.4.0-base
Thanks
You need to have sudo privileges.
1 Modify docker-compose.* file for MongoDB container and add new volume
Suppose you have something like this:
mongo:
image: mongo:4.2
container_name: mongodb
ports:
- 27017:27017
volumes:
- "./local/path:/data/db"
- "./local/tmp/path:/home"
restart: always
command: --auth
2 You need to build
sudo docker-compose -f docker-compose.yml up -d
3 Copy inside ./local/tmp/path you dump folder and check if MongoDB container has access to it.
sudo docker ps
sudo docker exec -it mongodb_CONTAINER ID /bin/bash
# ls /home - If you see there dump folder, continue step 4
4 Now, execute MongoDB restore (you may do it inside MongoDB container)
mongorestore -d mew -c audioQuestions_Joker /home/dump/meteor
5 If you have restored successfully, update again docker-compose and remove - "./local/tmp/path:/home" and build.

docker-compose can't find file to inject to Postgresql when running a command

I'm trying to restore a .backup file to a Postgresql database. For that, I use a docker-compose file to launch a postgres docker container:
docker-compose.yml
postgresql:
image: postgres
restart: always
ports:
- "5432:5432"
environment:
- POSTGRES_USER:postgres
# - PGDATA:/var/lib/postgresql/data/pgdata/
volumes:
- ${PWD}/project/data/MX/bkup/data:/var/lib/postgresql
command:
- pg_restore -U postgres -d postgres /var/lib/postgresql/ph.backup
When I run my docker-compose file using the command:
docker-compose up postgresql
I get the error:
(virtual) med#nid:~/projects/project/pkg$ docker-compose up postgresql
Recreating pkg_postgresql_1 ...
Recreating pkg_postgresql_1 ... done
Attaching to pkg_postgresql_1
postgresql_1 | /usr/local/bin/docker-entrypoint.sh: line 176: /pg_restore -U postgres -d postgres /var/lib/postgresql/ph.backup: No such file or directory
pkg_postgresql_1 exited with code 127
This happens even though the file is inside the volume
med#nid:~/projects/project/pkg$ docker-compose exec postgresql bash
root#ab7dbe2b0232:/# cd /var/lib/postgresql/
root#ab7dbe2b0232:/var/lib/postgresql# ls -l
total 1054780
drwx------ 19 postgres postgres 4096 Oct 2 08:51 data
-r--r--r-- 1 postgres ssl-cert 1080082803 Sep 27 15:40 ph.backup
I tried to use the -h argument of pg_restore in the docker-compose command:
pg_restore -h tcp://`docker-machine ip default`:5432 -U postgres -d postgres /var/lib/postgresql/ph.backup
What works:
If I comment the command target in the docker-compose.yml, launch the docker container and run the command inside it I get to have the data injected!
Is there a fix for this, Meaning, is there a way to make the command work directly from the docker-compose.yml file?
There are two forms of Docker Compose command:. You should move the command up on to the same line
command: pg_restore -U postgres -d postgres /var/lib/postgresql/ph.backup
The form you have individually spells out each argument (in a YAML list); for example
command:
- /bin/ls
- -l
- -r
- -t
(Also consider just installing the PostgreSQL client tools on your host and running this outside of Docker; use localhost as the host name and the first number from the database container's ports: as the port number.)
The error comes from the form of the command configuration. If you inspect the finished postgres container (docker inspect <container-id>) the entrypoint and command look like this:
"Cmd": [
"pg_restore -U postgres -d postgres /var/lib/postgresql/ph.backup"
],
"Entrypoint": [
"docker-entrypoint.sh"
]
That practically means that the default entrypoint script docker-entrypoint
is executed with one argument which is the pg_restore command. At line 176 the script execs the passed in arguments (exec "$#").
The exec command needs a command and a list of arguments
exec [command [arguments]]
but in this case the command is the full string formed by pg_restore and its arguments. This obviously is not a valid file
Now, if you change command in docker-compose.yml to:
command: pg_restore -U postgres -d postgres /var/lib/postgresql/ph.backup
inspecting the container shows the following:
"Cmd": [
"pg_restore",
"-U",
"postgres",
"-d",
"postgres",
"/var/lib/postgresql/ph.backup"
]
that means that exec will run pg_restore as command passing the rest as arguments and everything works as expected.
In alternative you could override the entrypoint in the docker-compose file to execute the command in a shell:
entrypoint: /bin/bash -c
command:
- pg_restore -U postgres -d postgres /var/lib/postgresql/ph.backup

Customize the configuration of the official PostgreSQL docker image

I am using the official postgresql docker image (version 9.4). I have extended the Dockerfile, so I can alter the settings in the postgresql.conf etc, using a bash script. It successfully adds and runs the script on entrypoint, for a single sed command. But when I put 2 or more sed commands, I get the following error:
/docker-entrypoint.sh: running /docker-entrypoint-initdb.d/config.sh
: No such file or directoryread
/var/lib/postgresql/data/postgresql.conf
I am trying on Windows 10, in combination with Vagrant and VirtualBox, using NFS file system on shared folders, via the vagrant-winnfsd plugin.
Why is this happening? How can I alter my bash script in order to work with more configuration settings? Is there a better way?
Dockerfile:
FROM postgres:9.4
RUN echo "Europe/Athens" > /etc/timezone \
&& dpkg-reconfigure -f noninteractive tzdata
RUN localedef -i el_GR -c -f UTF-8 -A /usr/share/locale/locale.alias el_GR.UTF-8
ADD config.sh /docker-entrypoint-initdb.d/
RUN chmod 755 /docker-entrypoint-initdb.d/config.sh
VOLUME ["/etc/postgresql", "/var/log/postgresql", "/var/lib/postgresql"]
config.sh:
#!/bin/bash
sed -i -e"s/^#logging_collector = off.*$/logging_collector = on/" /var/lib/postgresql/data/postgresql.conf
sed -i -e"s/^max_connections = 100.*$/max_connections = 1000/" /var/lib/postgresql/data/postgresql.conf
database.yml
postgres:
container_name: postgres-9.4
image: ***/postgres-9.4
volumes_from:
- postgres_data
ports:
- 5432:5432
environment:
- POSTGRES_USER=user
- POSTGRES_PASSWORD=password
- POSTGRES_DB=database
- USERMAP_UID=999
- USERMAP_GID=999
postgres_data:
container_name: postgres_data
image: ***/postgres-9.4
volumes:
- ./services/postgres:/etc/postgresql
- ./services/postgres:/var/lib/postgresql
- ./services/postgres/logs:/var/log/postgresql
command: "true"
You might want to try using a RUN statement to execute your bash script or just run sed directly with both commands combined with a semicolon:
RUN sed -i -e 's/^#\(logging_collector = \).*/\1on/; s/^\(max_connections = \).*/\11000/' \
/var/lib/postgresql/data/postgresql.conf
A more scalable solution would be to put the sed program in an external file, then use these statements:
ADD postgres-edit.sed /var/local
RUN sed -i -f /var/local/postgres-edit.sed /var/lib/postgresql/data/postgresql.conf
postgres-edit.sed:
# sed script to edit postgresql configuration
s/^#\(logging_collector = \).*/\1on/
s/^\(max_connections = \).*/\11000/
Seems like a duplicate of How to customize the configuration file of the official PostgreSQL docker image?.
Copy-paste of my answer at https://stackoverflow.com/a/40598124/385548.
Inject custom postgresql.conf into postgres Docker container
The default postgresql.conf file lives within the PGDATA dir (/var/lib/postgresql/data), which makes things more complicated especially when running postgres container for the first time, since the docker-entrypoint.sh wrapper invokes the initdb step for PGDATA dir initialization.
To customize PostgreSQL configuration in Docker consistently, I suggest using config_file postgres option together with Docker volumes like this:
Production database (PGDATA dir as Persistent Volume)
docker run -d \
-v $CUSTOM_CONFIG:/etc/postgresql.conf \
-v $CUSTOM_DATADIR:/var/lib/postgresql/data \
-e POSTGRES_USER=postgres \
-p 5432:5432 \
--name postgres \
postgres:9.6 postgres -c config_file=/etc/postgresql.conf
Testing database (PGDATA dir will be discarded after docker rm)
docker run -d \
-v $CUSTOM_CONFIG:/etc/postgresql.conf \
-e POSTGRES_USER=postgres \
--name postgres \
postgres:9.6 postgres -c config_file=/etc/postgresql.conf
Debugging
Remove the -d (detach option) from docker run command to see the server logs directly.
Connect to the postgres server with psql client and query the configuration:
docker run -it --rm --link postgres:postgres postgres:9.6 sh -c 'exec psql -h $POSTGRES_PORT_5432_TCP_ADDR -p $POSTGRES_PORT_5432_TCP_PORT -U postgres'
psql (9.6.0)
Type "help" for help.
postgres=# SHOW all;

How to customize the configuration file of the official PostgreSQL Docker image?

I'm using the official Postgres Docker image, trying to customize its configuration. For this purpose, I use the command sed to change max_connections for example:
sed -i -e"s/^max_connections = 100.*$/max_connections = 1000/" /var/lib/postgresql/data/postgresql.conf
I tried two methods to apply this configuration:
The first is by adding the commands to a script and copying it within the init folder: /docker-entrypoint-initdb.d.
The second method is by running the commands directly within my Dockerfile with the "RUN" command (this method worked fine with a non-official PostgreSQL image with a different path to the configuration file /etc/postgres/...).
In both cases the changes fail because the configuration file is missing (I think it's not created yet).
How should I change the configuration?
Here is the Dockerfile used to create the image:
# Database (http://www.cs3c.ma/)
FROM postgres:9.4
MAINTAINER Sabbane <contact#cs3c.ma>
ENV TERM=xterm
RUN apt-get update
RUN apt-get install -y nano
ADD scripts /scripts
# ADD scripts/setup-my-schema.sh /docker-entrypoint-initdb.d/
# Allow connections from anywhere.
RUN sed -i -e"s/^#listen_addresses =.*$/listen_addresses = '*'/" /var/lib/postgresql/data/postgresql.conf
RUN echo "host all all 0.0.0.0/0 md5" >> /var/lib/postgresql/data/pg_hba.conf
# Configure logs
RUN sed -i -e"s/^#logging_collector = off.*$/logging_collector = on/" /var/lib/postgresql/data/postgresql.conf
RUN sed -i -e"s/^#log_directory = 'pg_log'.*$/log_directory = '\/var\/log\/postgresql'/" /var/lib/postgresql/data/postgresql.conf
RUN sed -i -e"s/^#log_filename = 'postgresql-\%Y-\%m-\%d_\%H\%M\%S.log'.*$/log_filename = 'postgresql_\%a.log'/" /var/lib/postgresql/data/postgresql.conf
RUN sed -i -e"s/^#log_file_mode = 0600.*$/log_file_mode = 0644/" /var/lib/postgresql/data/postgresql.conf
RUN sed -i -e"s/^#log_truncate_on_rotation = off.*$/log_truncate_on_rotation = on/" /var/lib/postgresql/data/postgresql.conf
RUN sed -i -e"s/^#log_rotation_age = 1d.*$/log_rotation_age = 1d/" /var/lib/postgresql/data/postgresql.conf
RUN sed -i -e"s/^#log_min_duration_statement = -1.*$/log_min_duration_statement = 0/" /var/lib/postgresql/data/postgresql.conf
RUN sed -i -e"s/^#log_checkpoints = off.*$/log_checkpoints = on/" /var/lib/postgresql/data/postgresql.conf
RUN sed -i -e"s/^#log_connections = off.*$/log_connections = on/" /var/lib/postgresql/data/postgresql.conf
RUN sed -i -e"s/^#log_disconnections = off.*$/log_disconnections = on/" /var/lib/postgresql/data/postgresql.conf
RUN sed -i -e"s/^log_line_prefix = '\%t \[\%p-\%l\] \%q\%u#\%d '.*$/log_line_prefix = '\%t \[\%p\]: \[\%l-1\] user=\%u,db=\%d'/" /var/lib/postgresql/data/postgresql.conf
RUN sed -i -e"s/^#log_lock_waits = off.*$/log_lock_waits = on/" /var/lib/postgresql/data/postgresql.conf
RUN sed -i -e"s/^#log_temp_files = -1.*$/log_temp_files = 0/" /var/lib/postgresql/data/postgresql.conf
RUN sed -i -e"s/^#statement_timeout = 0.*$/statement_timeout = 1800000 # in milliseconds, 0 is disabled (current 30min)/" /var/lib/postgresql/data/postgresql.conf
RUN sed -i -e"s/^lc_messages = 'en_US.UTF-8'.*$/lc_messages = 'C'/" /var/lib/postgresql/data/postgresql.conf
# Performance Tuning
RUN sed -i -e"s/^max_connections = 100.*$/max_connections = 1000/" /var/lib/postgresql/data/postgresql.conf
RUN sed -i -e"s/^shared_buffers =.*$/shared_buffers = 16GB/" /var/lib/postgresql/data/postgresql.conf
RUN sed -i -e"s/^#effective_cache_size = 128MB.*$/effective_cache_size = 48GB/" /var/lib/postgresql/data/postgresql.conf
RUN sed -i -e"s/^#work_mem = 1MB.*$/work_mem = 16MB/" /var/lib/postgresql/data/postgresql.conf
RUN sed -i -e"s/^#maintenance_work_mem = 16MB.*$/maintenance_work_mem = 2GB/" /var/lib/postgresql/data/postgresql.conf
RUN sed -i -e"s/^#checkpoint_segments = .*$/checkpoint_segments = 32/" /var/lib/postgresql/data/postgresql.conf
RUN sed -i -e"s/^#checkpoint_completion_target = 0.5.*$/checkpoint_completion_target = 0.7/" /var/lib/postgresql/data/postgresql.conf
RUN sed -i -e"s/^#wal_buffers =.*$/wal_buffers = 16MB/" /var/lib/postgresql/data/postgresql.conf
RUN sed -i -e"s/^#default_statistics_target = 100.*$/default_statistics_target = 100/" /var/lib/postgresql/data/postgresql.conf
VOLUME ["/var/lib/postgresql/data", "/var/log/postgresql"]
CMD ["postgres"]
With this Dockerfile, the build process produces an error:
sed: can't read /var/lib/postgresql/data/postgresql.conf: No such file or directory
With Docker Compose
When working with Docker Compose, you can use command: postgres -c option=value in your docker-compose.yml to configure Postgres.
For example, this makes Postgres log to a file:
command: postgres -c logging_collector=on -c log_destination=stderr -c log_directory=/logs
Adapting Vojtech Vitek's answer, you can use
command: postgres -c config_file=/etc/postgresql.conf
to change the config file Postgres will use. You'd mount your custom config file with a volume:
volumes:
- ./customPostgresql.conf:/etc/postgresql.conf
Here's the docker-compose.yml of my application, showing how to configure Postgres:
# Start the app using docker-compose pull && docker-compose up to make sure you have the latest image
version: '2.1'
services:
myApp:
image: registry.gitlab.com/bullbytes/myApp:latest
networks:
- myApp-network
db:
image: postgres:9.6.1
# Make Postgres log to a file.
# More on logging with Postgres: https://www.postgresql.org/docs/current/static/runtime-config-logging.html
command: postgres -c logging_collector=on -c log_destination=stderr -c log_directory=/logs
environment:
# Provide the password via an environment variable. If the variable is unset or empty, use a default password
# Explanation of this shell feature: https://unix.stackexchange.com/questions/122845/using-a-b-for-variable-assignment-in-scripts/122848#122848
- POSTGRES_PASSWORD=${POSTGRES_PASSWORD:-4WXUms893U6j4GE&Hvk3S*hqcqebFgo!vZi}
# If on a non-Linux OS, make sure you share the drive used here. Go to Docker's settings -> Shared Drives
volumes:
# Persist the data between container invocations
- postgresVolume:/var/lib/postgresql/data
- ./logs:/logs
networks:
myApp-network:
# Our application can communicate with the database using this hostname
aliases:
- postgresForMyApp
networks:
myApp-network:
driver: bridge
# Creates a named volume to persist our data. When on a non-Linux OS, the volume's data will be in the Docker VM
# (e.g., MobyLinuxVM) in /var/lib/docker/volumes/
volumes:
postgresVolume:
Permission to write to the log directory
Note that when on Linux, the log directory on the host must have the right permissions.
Otherwise you'll get the slightly misleading error
FATAL: could not open log file
"/logs/postgresql-2017-02-04_115222.log": Permission denied
I say misleading, since the error message suggests that the directory in the container has the wrong permission, when in reality the directory on the host doesn't permit writing.
To fix this, I set the correct permissions on the host using
chgroup ./logs docker && chmod 770 ./logs
The postgres:9.4 image you've inherited from declares a volume at /var/lib/postgresql/data. This essentially means you can't copy any files to that path in your image; the changes will be discarded.
You have a few choices:
You could just add your own configuration files as a volume at run-time with docker run -v postgresql.conf:/var/lib/postgresql/data/postgresql.conf .... However, I'm not sure exactly how that will interact with the existing volume.
You could copy the file over when the container is started. To do that, copy your file into the build at a location which isn't underneath the volume then call a script from the entrypoint or cmd which will copy the file to the correct location and start Postgres.
Clone the project behind the Postgres official image and edit the Dockerfile to add your own config file in before the VOLUME is declared (anything added before the VOLUME instruction is automatically copied in at run-time).
Pass all config changes in command option in docker-compose file
Like this:
services:
postgres:
...
command:
- "postgres"
- "-c"
- "max_connections=1000"
- "-c"
- "shared_buffers=3GB"
- "-c"
...
When you run the official entrypoint (i.e, when you launch the container), it runs initdb in $PGDATA (/var/lib/postgresql/data by default), and then it stores two files in that directory:
postgresql.conf with default manual settings.
postgresql.auto.conf with settings overriden automatically with ALTER SYSTEM commands.
The entrypoint also executes any /docker-entrypoint-initdb.d/*.{sh,sql} files.
All this means you can supply a shell/SQL script in that folder that configures the server for the next boot (which will be immediately after the DB initialization, or the next time you boot the container).
Example:
conf.sql file:
ALTER SYSTEM SET max_connections = 6;
ALTER SYSTEM RESET shared_buffers;
Dockerfile file:
FROM posgres:9.6-alpine
COPY *.sql /docker-entrypoint-initdb.d/
RUN chmod a+r /docker-entrypoint-initdb.d/*
And then you will have to execute conf.sql manually in the already existing databases. Since configuration is stored in the volume, it will survive rebuilds.
An alternative is to pass the -c option as many times as you wish:
docker container run -d postgres -c max_connections=6 -c log_lock_waits=on
This way, you don't need to build a new image, and you don't need to care about already existing or not databases; all will be affected.
Inject custom postgresql.conf into Postgres Docker container
The default postgresql.conf file lives within the PGDATA dir (/var/lib/postgresql/data), which makes things more complicated especially when running the Postgres container for the first time, since the docker-entrypoint.sh wrapper invokes the initdb step for PGDATA dir initialization.
To customize the PostgreSQL configuration in Docker consistently, I suggest using the config_file Postgres option together with Docker volumes like this:
Production database (PGDATA dir as Persistent Volume)
docker run -d \
-v $CUSTOM_CONFIG:/etc/postgresql.conf \
-v $CUSTOM_DATADIR:/var/lib/postgresql/data \
-e POSTGRES_USER=postgres \
-p 5432:5432 \
--name postgres \
postgres:9.6 postgres -c config_file=/etc/postgresql.conf
Testing database (PGDATA dir will be discarded after docker rm)
docker run -d \
-v $CUSTOM_CONFIG:/etc/postgresql.conf \
-e POSTGRES_USER=postgres \
--name postgres \
postgres:9.6 postgres -c config_file=/etc/postgresql.conf
Debugging
Remove the -d (detach option) from docker run command to see the server logs directly.
Connect to the Postgres server with the psql client and query the configuration:
docker run -it --rm --link postgres:postgres postgres:9.6 sh -c 'exec psql -h $POSTGRES_PORT_5432_TCP_ADDR -p $POSTGRES_PORT_5432_TCP_PORT -U postgres'
psql (9.6.0)
Type "help" for help.
postgres=# SHOW all;
You can put your custom postgresql.conf in a temporary file inside the container, and overwrite the default configuration at runtime.
To do that:
Copy your custom postgresql.conf inside your container
Copy the updateConfig.sh file in /docker-entrypoint-initdb.d/
Dockerfile
FROM postgres:9.6
COPY postgresql.conf /tmp/postgresql.conf
COPY updateConfig.sh /docker-entrypoint-initdb.d/_updateConfig.sh
updateConfig.sh
#!/usr/bin/env bash
cat /tmp/postgresql.conf > /var/lib/postgresql/data/postgresql.conf
At runtime, the container will execute the script inside /docker-entrypoint-initdb.d/ and overwrite the default configuration with your custom one.
I looked through all the answers and there is another option left: You can change your CMD value in the Dockerfile (it is not the best one, but still a possible way to achieve your goal).
Basically we need to:
Copy the config file into the Docker container
Override Postgres start options
Dockerfile example:
FROM postgres:9.6
USER postgres
# Copy Postgres config file into container
COPY postgresql.conf /etc/postgresql
# Override default Postgres config file
CMD ["postgres", "-c", "config_file=/etc/postgresql/postgresql.conf"]
Though I think using command: postgres -c config_file=/etc/postgresql/postgresql.conf in your docker-compose.yml file as proposed by Matthias Braun is the best option.
I was also using the official image (FROM postgres)
and I was able to change the config by executing the following commands.
The first thing is to locate the PostgreSQL config file.
This can be done by executing this command in your running database.
SHOW config_file;
I my case it returns /data/postgres/postgresql.conf.
The next step is to find out what is the hash of your running PostgreSQL docker container.
docker ps -a
This should return a list of all the running containers. In my case it looks like this.
...
0ba35e5427d9 postgres "docker-entrypoint.s…" ....
...
Now you have to switch to the bash inside your container by executing:
docker exec -it 0ba35e5427d9 /bin/bash
Inside the container check if the config is at the correct path and display it.
cat /data/postgres/postgresql.conf
I wanted to change the max connections from 100 to 1000 and the shared buffer from 128MB to 3GB.
With the sed command I can do a search and replace with the corresponding variables ins the config.
sed -i -e"s/^max_connections = 100.*$/max_connections = 1000/" /data/postgres/postgresql.conf
sed -i -e"s/^shared_buffers = 128MB.*$/shared_buffers = 3GB/" /data/postgres/postgresql.conf
The last thing we have to do is to restart the database within the container.
Find out which version you of PostGres you are using.
cd /usr/lib/postgresql/
ls
In my case its 12
So you can now restart the database by executing the following command with the correct version in place.
su - postgres -c "PGDATA=$PGDATA /usr/lib/postgresql/12/bin/pg_ctl -w restart"
A fairly low-tech solution to this problem seems to be to declare the service (I'm using swarm on AWS and a yaml file) with your database files mounted to a persisted volume (here AWS EFS as denoted by the cloudstor:aws driver specification).
version: '3.3'
services:
database:
image: postgres:latest
volumes:
- postgresql:/var/lib/postgresql
- postgresql_data:/var/lib/postgresql/data
volumes:
postgresql:
driver: "cloudstor:aws"
postgresql_data:
driver: "cloudstor:aws"
The db comes up as initialized with the image default settings.
You edit the conf settings inside the container, e.g if you want to increase the maximum number of concurrent connections that requires a restart
stop the running container (or scale the service down to zero and then back to one)
the swarm spawns a new container, which this time around picks up your persisted configuration settings and merrily applies them.
A pleasant side-effect of persisting your configuration is that it also persists your databases (or was it the other way around) ;-)
My solution is for colleagues who needs to make changes in config before launching docker-entrypoint-initdb.d
I was needed to change 'shared_preload_libraries' setting so during it's work postgres already has new library preloaded and code in docker-entrypoint-initdb.d can use it.
So I just patched postgresql.conf.sample file in Dockerfile:
RUN echo "shared_preload_libraries='citus,pg_cron'" >> /usr/share/postgresql/postgresql.conf.sample
RUN echo "cron.database_name='newbie'" >> /usr/share/postgresql/postgresql.conf.sample
And with this patch it become possible to add extension in .sql file in docker-entrypoint-initdb.d/:
CREATE EXTENSION pg_cron;
Using docker compose you can mount a volume with postgresql.auto.conf.
Example:
version: '2'
services:
db:
image: postgres:10.9-alpine
volumes:
- postgres:/var/lib/postgresql/data:z
- ./docker/postgres/postgresql.auto.conf:/var/lib/postgresql/data/postgresql.auto.conf
ports:
- 5432:5432