Dockerized PGAdmin Mapped volume + COPY not working - postgresql

I have a scenario where a certain data set comes from a CSV and I need to allow a non-dev to hit PG Admin and update this data set. I want to be able to put this CSV in a mapped folder from the host system and then use the PG Admin GUI to run a COPY command. So far PG Admin is telling me:
ERROR: could not open file "/var/lib/pgadmin/data-files/some_data.csv" for reading: No such file or directory
Here are my steps so far, along with a sanity check inspect:
docker volume create --name=data-files
docker run -e PGADMIN_DEFAULT_EMAIL="pgadmin#example.com" -e PGADMIN_DEFAULT_PASSWORD=some_pass -v data-files:/var/lib/pgadmin/data-files -d -p 5050:80 --name pgadmin dpage/pgadmin4
docker volume inspect data-files --format '{{.Mountpoint}}'
/app/docker/volumes/data-files/_data
docker cp ./updated-data.csv pgadmin:/var/lib/pgadmin/data-files
And, now I think that PG Admin could see the updated-data.csv, so I try COPY, which I know works locally on my dev system where PG Admin is on baremetal:
COPY foo.bar(
...
)
FROM '/var/lib/pgadmin/data-files/updated-data.csv'
DELIMITER ','
CSV HEADER
ENCODING 'windows-1252';
Is there any glaring mistake here? When I do docker cp there's no feedback to stdout. No error, no mention of success or a hash or anything.

It looks like you thought the file should be inside the pgadmin container however the file you are going to copy must be inside the postgres container so the query you run will find the file. I suggest you copy the file to postgres container :
docker cp <path_from_your_local>/file.csv <postgres_container_name>:/file.csv
Then in the query tool from your pgadmin you can copy without problems !
I hope this help to others came here...

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

Locust not generating failures.csv and expections.csv in distributed mode without UI in docker

When testing API using locust distributed mode without UI in docker. The distribution.csv, requests.csv are getting generated but the failures.csv and expection.csv are not getting generated but the requests.csv show failures as given below.
"Method","Name","# requests","# failures","Median response time","Average response time","Min response time","Max response time","Average Content Size","Requests/s"
"POST","/api/something/something",197009,56,470,559,78,156714,1,436.31
Can you please help.
The problem is that file need to be written to a folder that it has permission to, and a volume that is mounted to your host. If you add a mounted folder before the file name, it should work. For example:
Docker file:
# Set base image
FROM locustio/locust
ADD locustfile.py locustfile.py
Docker create Command:
docker build -t mykey/myimage:1.0 .
Docker run command (on Windows, replace with %CD% with $pwd on linux):
docker run --volume "%CD%:/mnt/locust" -e LOCUSTFILE_PATH=/mnt/locust/locustfile.py -e TARGET_URL=https://example.com -e LOCUST_OPTS="--clients=10 --no-web --run-time=600 --csv=/mnt/locust/output" mykey/myimage:1.0
The files will now write to the same folder where locustfile.py is located.

run pg_dump in a docker container and output file to host

We typically have to pg_dump from multiple different versions of databases. I want to run the command inside a Docker container with the right Postgres version and have the dump output to my files rather than the container.
I thought I'd achieve it like so;
docker run -it postgres:9.6.6-alpine pg_dump --file backupFile.bak --dbname=CONNECTIONSTRING --verbose --format=c --blobs > backupFile.bak
however this just outputs the terminal output of the pg_dump command to a file, not the actual dump. I end up with a local file that's just the verbose log of the command.
What am I missing?
I can think of two options here:
Mount a volume to a local folder and dump the file there. When the container exits, the file will still be there on the host. You wouldn't need to run the container interactively. The command might look something like this (not tested):
docker run --rm -v <host_folder>:<container_folder> postgres:9.6.6-alpine pg_dump --file backupFile.bak --dbname=CONNECTIONSTRING --verbose --format=c --blobs
The backup file will still remain in <host_folder> after the container stops.
Start the container as-is, run docker cp to pull the file out of the container to the local filesystem, then stop the container. Probably not as easy or efficient as option 1.

psql, can't copy db content to another - cannot run inside a transaction block-

I'd like to copy the content of my local machine to my remote one (inside a docker).
For some reason, it is more complicated that I was expected:
When I try to copy the data to the remote one, I get this "ERROR: CREATE DATABASE cannot run inside a transaction block".
Ok... So I get into my docker container, added the rule \set AUTOCOMMIT inside. But I still get this error.
This is the command I did:
// backup
pg_dump -C -h localhost -U postgres woof | xz >backup.xz
and then in my remote computer:
xz -dc backup.xz | docker exec -i -u postgres waf-postgres psql --set ON_ERROR_STOP=on --single-transaction
But each time I get this "CREATE DATABASE cannot run inside a transaction block" no matter what I try. Even if I put the autocommit to "on".
Here my problem: I don't know what a transaction block is. And I don't understand why copying one db to another need to be so hard pain: My remote db is empty. So why there is so much fuss and why psql just can't force what I want?
My aim is just to copy my local db to the remote one.
what happens here is: you add CREATE DATABASE statement with -C key and then try to run psql with --single-transaction, so the content of script are wrapped to BEGIN;...END;, where you can't use CREATE DATABASE
So iether remove -C and run psql against existing database, or remove --single-transaction for psql. Make decision based on what you really need...
from man pg_dump:
-C
--create
Begin the output with a command to create the database itself and reconnect to the created database. (With a script of this
form, it doesn't matter which database in the destination installation
you connect to before
running the script.) If --clean is also specified, the script drops and recreates the target database before reconnecting to
it.
from man psql:
--single-transaction
This option can only be used in combination with one or more -c and/or -f options. It causes psql to issue a BEGIN command
before the first such option and a COMMIT command after the last one, thereby wrapping all the commands into a single
transaction. This ensures that either all the commands complete successfully, or no changes are applied.

Boot2Docker (on Windows) running Mongo with shared folder (This file system is not supported)

I am trying to start a Mongo container using shared folders on Windows using Boot2Docker. When starting using run -it -v /c/Users/310145787/Desktop/mongo:/data/db mongo i get a warning message inside the container saying:
WARNING: This file system is not supported.
After starting mongo shutsdown immediately.
Any hints or tips on how to solve this?
Apparently, according to this gist and Sev (sevastos), mongo doesn't support mounted volume through the VirtualBox shared folder:
See mongoDB Productions Notes:
MongoDB requires a filesystem that supports fsync() on directories.
For example, HGFS and Virtual Box’s shared folders do not support this operation.
the easiest solutions of all and a proper way for data persistance is Data Volumes:
Assuming you have a container that has VOLUME ["/data"]
# Create a data volume
docker create -v /data --name yourData busybox true
# and use
docker run --volumes-from yourData ...
This isn't always ideal (but the following is for Mac, by Edward Chu (chuyik)):
I don't think it's a good solution, because the data just moved to another container right?
But it still inside the container rather than local system(mac disk).
I found another solution, that is to use sshfs to map data between boot2docker vm and your mac, which may be better since data is not stored inside linux container.
Create a directory to store data inside boot2docker:
boot2docker ssh
mkdir -p /mnt/sda1/dev
Use sshfs to link boot2docker and mac:
echo tcuser | sshfs docker#localhost:/mnt/sda1/dev <your mac dir path> -p 2022 -o password_stdin
Run image with mongo installed:
docker run -v /mnt/sda1/dev:/data/db <mongodb-image> mongod
The corresponding boot2docker issue points out to docker issue 12590 ( Problem with -v shared folders in 1.6 #12590), which points to the work around of using double-slash.
using a double slash seems to work. I checked it locally and it works.
docker run -d -v //c/Users/marco/Desktop/data:/data <image name>
it also works with
docker run -v /$(pwd):/data
As an workaround I just copy from a folder before mongo deamon starts. Also, in my case I don't care of journal files, so i only copy database files.
I've used this command on my docker-compose.yml
command: bash -c "(rm /data/db/*.lock && cd /prev && cp *.* /data/db) && mongod"
And everytime before stoping the container I use:
docker exec <container_name> bash -c 'cd /data/db && cp $(ls *.* | grep -v *.lock) /prev'
Note: /prev is set as a volume. path/to/your/prev:/prev
Another workaround is to use mongodump and mongorestore.
in docker-compose.yml: command: bash -c "(sleep 30; mongorestore
--quiet) & mongod"
in terminal: docker exec <container_name> mongodump
Note: I use sleep because I want to make sure that mongo started, and it takes a while.
I know this involves manual work etc, but I am happy that at least I got mongo with existing data running on my Windows 10 machine, and still can work on my Macbook when I want.
It's seems like you don't need the data directory for MongoDb, removing those lines from your docker-composer.yml should run without problems.
The data directory is only used by mongo for cache.