Config file syntax: secrets from file in key=value

[Aki Tuomi]

> On 06/09/2022 16:31 EEST Tobias Florek <dovecot at ibotty.net> wrote:
> 
>  
> Hi!
> 
> I'd like to set up proxy authentication. This works fine, but I cannot 
> get the passwords in  to be read from file.
> 
> Specifically I have this passdb block.
> 
> passdb {
>    driver = passwd-file
>    mechanisms = plain scram-sha-256
>    default_fields = proxy=y host=dovecot-backend 
> master=imapc-master-user proxy_mech=plain 
> pass=</run/secrets/dovecot.imapc-master-user/password
>    args = /run/secrets/dovecot.generated.app-passwd-file/passwd
> }
> 
> This sets the password to the string 
> /run/secrets/dovecot.imapc-master-user/password.  I'd like the password 
> to be set to the content of said file.
> 
> Is it possible to get the password from a file or less desirable from 
> the environment?  Reading 
> https://doc.dovecot.org/configuration_manual/config_file/ I assume it's not.
> 
> Cheers,
>   Tobias Florek

You can use $ENV:variable syntax with Dovecot v2.3.14+. The environment variable needs to be listed in `import_environment` setting and be available for dovecot process on startup.

It's enough to just mention the variable in import_environment, it does not need to be assigned there.

Aki