Simplifying setup: don't use any parameters

We can do this by using the driver and server_version config. Then, we
can just set DATABASE_URL to blank, to supress the error that it does
not exist. If it *is* set, it overrides the driver option, but they
should match anyways.

doctrine/doctrine-bundle/1.6/config/packages/doctrine.yaml

@@ -1,15 +1,18 @@
 parameters:
-    # adds a fallback URL if the env var is not set
-    # this is useful to allow you to run cache:warmup
-    # even when your environment variables don't yet exist
-    # you should not need to change this value
-    env(DATABASE_URL): '%doctrine.database_server%://'
+    # Adds a fallback DATABASE_URL if the env var is not set.
+    # This allows you to run cache:warmup even if your
+    # environment variables are not available yet.
+    # You should not need to change this value.
+    env(DATABASE_URL): ''
 
 doctrine:
     dbal:
+        # configure these for your database server
+        driver: 'pdo_mysql'
+        server_version: '5.7'
+
         # With Symfony 3.3, remove the `resolve:` prefix
         url: '%env(resolve:DATABASE_URL)%'
-        server_version: '%doctrine.server_version%'
     orm:
         auto_generate_proxy_classes: '%kernel.debug%'
         naming_strategy: doctrine.orm.naming_strategy.underscore

doctrine/doctrine-bundle/1.6/manifest.json

@@ -11,9 +11,5 @@
         "#2": "For an SQLite database, use: \"sqlite:///%kernel.project_dir%/var/data.db\"",
         "#3": "Set \"serverVersion\" to your server version to avoid edge-case exceptions and extra database calls",
         "DATABASE_URL": "mysql://db_user:db_password@127.0.0.1:3306/db_name?charset=utf8mb4"
-    },
-    "container": {
-        "doctrine.database_server": "mysql",
-        "doctrine.server_version": "5.7"
     }
 }

doctrine/doctrine-bundle/1.6/post-install.txt

@@ -1,8 +1,8 @@
-<bg=blue;fg=white>                         </>
-<bg=blue;fg=white> Configure your database </>
-<bg=blue;fg=white>                         </>
+<bg=blue;fg=white>                      </>
+<bg=blue;fg=white> Next: Configuration  </>
+<bg=blue;fg=white>                      </>
 
   * Modify your DATABASE_URL config in <fg=green>.env</>
 
-  * Configure the <fg=green>database_server</> (mysql) and
-    <fg=green>server_version</fg> (5.7) in <fg=green>config/services.yaml</>
+  * Configure the <fg=green>driver</> (mysql) and
+    <fg=green>server_version</fg> (5.7) in <fg=green>config/packages/doctrine.yaml</>