Indeed, that's not supported. Parameters are static and should not be expressions. I will see how to raise an exception in this case.

Please don't. I really need this feature in a multitenant application. Having an app for each tenant uses way to many memory.
edit: maybe a closure could be dumped into the array if it cannot be solved otherwise.
Or such parameters should be dumped into another function e.g. getExpressionParameter

Ah the case with session works partially because that specific session is defined as a service in config.yml.
So It seems that this doesn't work at all.
Which is the shame. It would be really nice if some settings inside config.* files could be dynamic e.g configured with Expression engine.

Can't your issue be solved by overriding the session service ?

What about allowing expressions but without access to the container ? Only parameters

@adrienbrault I don't think this is worth it as you can already use parameter values in a parameter: foo %foo%

@michelsalib: The session is just one service that needs to be configured on the fly. There are others. e.g framework seecret, remember me key,...

How about several prod_env switched in app.php by reading the Server variable ?

Quick, maybe dirty but afterall that's what you want.

Michel Salib

De : Miha Vrhovnikmailto:notifications@github.com
Envoyé : ‎09/‎12/‎2013 09:17
À : symfony/symfonymailto:symfony@noreply.github.com
Cc : Michel Salibmailto:michelsalib@hotmail.com
Objet : Re: [symfony] Expression engine doesn't handle expressions inside parameters (#9658)

@michelsalib: The session is just one service that needs to be configured on the fly. There are others.

Reply to this email directly or view it on GitHub:
#9658 (comment)

Having an app per tenant doesn't scale. Just run an app with enabled ZendOptimizer and look at the memory consumed by files in app. The other thing is. upgrading application in such a scenario would be a nightmare

I know this is an old thread. But recently I had to define redundant parameters. I had to define the locale for routes, and the same locales but as an array for a different parameter. e.g

parameters:
    locale: en|np
    supported_locales: [en, np]

The locale parameter is for the framework config, and supported_locales for a custom bundle.

This is a whitelabel product I am working on, so these values will be different for different installations.
And adding a new locale requires editing 2 values, which sometimes people forget. It would be really great if we could do something like

parameters:
    locale: en|np
    supported_locales: (%locale%).split("|")  #don't mind the syntax, you get what I am trying to say here

@broncha what you could do is having a single parameter defined in the parameters.yml file, and having the DI extension of a bundle set the other one based on the first one.

@stof yes I could do that. I just mentioned it as an example, and there could be many other cases. That would be a kind of syntatic sugar.

@michelsalib @fabpot Can you fix this?

Environment variables are key for deployment configuration in modern applications (12factor.net). But dumping sensitive information like database passwords, API keys and other access credentials to disk is a security risk in multi-tenant environments. In addition to exposing access credentials in a known location the dumped container can be overwritten with malicious code by anyone using the webserver without even escalating privileges in most cases.

It is also a scalability issue. Networked filesystems (NFS, AFS, etc) generally are notoriously bad at negotiating write locks and local storage means a waste of resources if each machine compiles the container for itself.

At least there should be a check or path postfix indicating whether the environment variables have changed to avoid running with stale configs.

@b7kich do you actually have a use case for defining parameters dynamically based on credentials ? This is what this issue is about.

If you just want to configure services based on env variables, this is possible in Symfony 3.2 already.

anyway, commenting on an issue closed 1 year ago is probably not the best place to discuss your own issue.

Hi @stof - sorry if I wasn't clear enough or got off on a tangent. I'll check out the 3.2 branch.

I use an expression extension to dynamically configure sensitive parameters from environment variables but it could be anything else. I do use the SYMFONY__ env prefix and %% for regular parameters and the expression extension works fine for all my services. Where it doesn't is e.g. the doctrine dbal connection credentials or framework.secret.

beautiful - env injection works perfectly in 3.2. Thanks for the hint!