There are multiple problems with a typical approach to configuration:
In order to solve these issues Yii introduces a simple environments concept. Each environment is represented
by a set of files under the environments
directory. The init
command is used to initialize an environment. What it really does is
copy everything from the environment directory over to the root directory where all applications are.
By default there are two environments: dev
and prod
. First is for development. It has all the developer tools
and debug turned on. Second is for server deployments. It has debug and developer tools turned off.
Typically environment contains application bootstrap files such as index.php
and config files suffixed with
-local.php
. These are either personal configs of team members which are usually in dev
environment or configs of
specific servers. For example, production database connection could be in prod
environment -local.php
config.
These local configs are added to .gitignore
and never pushed to source code repository.
In order to avoid duplication configurations are overriding each other. For example, the frontend reads configuration in the following order:
common/config/main.php
common/config/main-local.php
frontend/config/main.php
frontend/config/main-local.php
Parameters are read in the following order:
common/config/params.php
common/config/params-local.php
frontend/config/params.php
frontend/config/params-local.php
The later config file overrides the former.
Here's the full scheme: