POSTGRES_PASSWORD_FILE or POSTGRES_DB_PASSWORD_FILE

[vasicvuk]

In documentation for Docker secret POSTGRES_PASSWORD_FILE is used. With 9.6:apline version password from Secret is not set but when i use ENV variable POSTGRES_DB_PASSWORD_FILE it works.

Should it be POSTGRES_DB_PASSWORD_FILE as it is in documentation or it is error ?

[yosifkit]

It shouldn't be _DB_ for any of the variables we use. There is a comment about XYZ_DB_PASSWORD, but it is wrong and the only place mentioning _DB_PASSWORD.

postgres/9.6/alpine/docker-entrypoint.sh

Lines 65 to 66 in b7cb3c6

	file_env 'POSTGRES_PASSWORD'
	if [ "$POSTGRES_PASSWORD" ]; then

$ echo 'secret' > notpasswords
$ docker run -d --name pg -e POSTGRES_PASSWORD_FILE=/notpasswords -v "$PWD/notpasswords:/notpasswords" postgres:9.6-alpine
$ docker run -it --rm --link pg postgres:9.6 bash
root@c37d1f3f2910:/# psql -h pg -U postgres
Password for user postgres: 
psql (9.6.5)
Type "help" for help.

postgres=#

[yosifkit]

I did find one source mentioning POSTGRES_DB_PASSWORD_FILE, and it was on Docker's blog with its related dockersamples/atsea-shop-app`. I made a PR to fix: dockersamples/atsea-sample-shop-app#100.

[vasicvuk]

With 9.6 alpine version POSTGRES_PASSWORD_FILE is not working but POSTGRES_DB_PASSWORD_FILE works. Looking at the image source i also didn't find POSTGRES_DB_PASSWORD_FILE anywhere but there is actually a problem that POSTGRES_PASSWORD_FILE is ignored somehow.

Maybe the author of repository also had problem with POSTGRES_PASSWORD_FILE so he also did use POSTGRES_DB_PASSWORD_FILE

[tianon]

You're probably getting a successful database from "POSTGRES_DB_PASSWORD_FILE", but I'd wager that your logs have a note informing you that your database is actually passwordless. Can you please provide a simple way to reproduce the issue with "POSTGRES_PASSWORD_FILE"? (because we cannot seem to reproduce it)

[yosifkit]

Is it a completely new database each time? If you are reusing the database files via a volume/bind mount, the initialization will not happen and a new password will not be set. See #203 (comment).

[vasicvuk]

You are right. POSTGRES_DB_PASSWORD_FILE will not create password at all. I found out that when creating a secret from Windows echo command ads new line at the end of the secret (\r\n) and that is not trimmed inside Docker image when putting password over (POSTGRES_PASSWORD_FILE) so i guess that is the problem

[tianon]

Glad you got it figured out! 👍

[azdrojowa123]

You are right. POSTGRES_DB_PASSWORD_FILE will not create password at all. I found out that when creating a secret from Windows echo command ads new line at the end of the secret (\r\n) and that is not trimmed inside Docker image when putting password over (POSTGRES_PASSWORD_FILE) so i guess that is the problem

Thank you very much !
I was dealing with it for a day