Bootstrapped databases with best practice role setup (#843)

* PreparedDatabases with default role setup

* merge changes from master

* include preparedDatabases spec check when syncing databases

* create a default preparedDB if not specified

* add more default privileges for schemas

* use empty brackets block for undefined objects

* cover more default privilege scenarios and always define admin role

* add DefaultUsers flag

* support extensions and defaultUsers for preparedDatabases

* remove exact version in deployment manifest

* enable CRD validation for new field

* update generated code

* reflect code review

* fix typo in SQL command

* add documentation for preparedDatabases feature + minor changes

* some datname should stay

* add unit tests

* reflect some feedback

* init users for preparedDatabases also on update

* only change DB default privileges on creation

* add one more section in user docs

* one more sentence

manifests/complete-postgres-manifest.yaml

@@ -21,6 +21,17 @@ spec:
   - 127.0.0.1/32
   databases:
     foo: zalando
+  preparedDatabases:
+    bar:
+      defaultUsers: true
+      extensions:
+        pg_partman: public
+        pgcrypto: public
+      schemas:
+        data: {}
+        history:
+          defaultRoles: true
+          defaultUsers: false
   postgresql:
     version: "12"
     parameters: # Expert section

manifests/minimal-postgres-manifest.yaml

@@ -15,5 +15,7 @@ spec:
     foo_user: []  # role for application foo
   databases:
     foo: zalando  # dbname: owner
+  preparedDatabases:
+    bar: {}
   postgresql:
     version: "12"

manifests/postgresql.crd.yaml

@@ -237,6 +237,26 @@ spec:
                   type: object
                   additionalProperties:
                     type: string
+            preparedDatabases:
+              type: object
+              additionalProperties:
+                type: object
+                properties:
+                  defaultUsers:
+                    type: boolean
+                  extensions:
+                    type: object
+                    additionalProperties:
+                      type: string
+                  schemas:
+                    type: object
+                    additionalProperties:
+                      type: object
+                      properties:
+                        defaultUsers:
+                          type: boolean
+                        defaultRoles:
+                          type: boolean
             replicaLoadBalancer:  # deprecated
               type: boolean
             resources: