Symfony2 bundle configuration parameters - symfony

Question

My team develops a very large e-commerce project. Up to now, we had something like 40 configuration parameters in that bundle and I didn't know their final relations nor had a way to structure them properly, so we ended up using the standard parameters structure in the app/config.yml file. But, somewhere along the way I decided to move the config to the semantic configuration structure - so I can validate it, have a clean structure, easily extend it by means of bundle inheritance and so on.
The problem is I can't import our bundle parameters to another bundle config, now.
Here's what I could do before:
(...)
parameters:
company.bundle.email.user: user#domain.com
company.bundle.email.pass: #MyBeAUtiFULpA55w0Rd!
(...)
swiftmailer:
(...)
username: %company.bundle.email.user%
password: %company.bundle.email.pass%
Here's what I'm trying to do now and it doesn't work at all:
(...)
company_bundle:
(...)
settings:
(...)
mailer:
(...)
user: user#domain.com
pass: #MyBeAUtiFULpA55w0Rd!
(...)
swiftmailer:
(...)
username: %company_bundle.settings.mailer.user%
password: %company_bundle.settings.mailer.pass%
(...)
Of course the company_bundle node contains the semantic configuration, processed by the DIC and defined in Company\Bundle\DependencyInjection\Configuration.php.
All I end up with for now is the following error:
[Symfony\Component\DependencyInjection\Exception\ParameterNotFoundException]
You have requested a non-existent parameter "company_bundle.settings.mailer.user".
So the question is: how to make my bundle parameters accessible in another bundle configuration parameters (I've already taken care of including my bundle configuration always before the Swiftmailer bundle)?
NOTICE: Swiftmailer bundle configuration is shown here only for demonstration purposes, I want to be able to reuse my bundle parameters across some other bundles as well.
What's the motivation behind that?
Well I want our product to be configured by a person who doesn't know Symfony well - so she must be able to open our bundle config file and just tweak the parameters, which will then be used in some Symfony bundles we use. So I want all application configuration to be accessible in our bundle's semantic conf, since I'd want not to expose the whole configuration to that person (I've already divided everything into separate config files, one of them containing the configuration for our bundle, the rest - for all the other ones).
So, is what I'm asking even possible?

Answer 1

As the parameters are to be modified in each installation (they probably differ at least between development and production environments), so (as Sgoettschkes said in comment) external file is the best solution.
In Symfony2 by default place for such parameters is parameters.yml file located in app/config/ dir.
In standard installation you can find for example such entries:
parameters:
database_driver: pdo_mysql
database_host: 127.0.0.1
(...)
These params are used in config.yml this way:
doctrine:
dbal:
driver: "%database_driver%"
host: "%database_host%"
(...)
So you can define your params (in parameters.yml):
parameters:
(...)
company_bundle_email_user: user#domain.com
company_bundle_email_pass: #MyBeAUtiFULpA55w0Rd!
and use them (in config.yml):
swiftmailer:
(...)
username: %company_bundle_email_user%
password: %company_bundle_email_pass%