[Docs] Add policy file description

Closes-Bug: #1463306
Change-Id: Id5444b873f21a873a37db18711889dd08a27a15d

doc/source/draft/admin-guide/installation.rst

@@ -12,3 +12,72 @@ Network configuration
 
 Policy configuration
 ~~~~~~~~~~~~~~~~~~~~
+
+Like each service in OpenStack, murano has its own role-based access policies
+that determine who and how can access objects. These policies are defined
+in the service's :file:`policy.json` file.
+
+On each API call corresponding policy check is performed.
+:file:`policy.json` file can be changed whiteout interrupting the API service.
+
+For detailed information on :file:`policy.json` syntax, please refer to the
+`OpenStack official documentation <http://docs.openstack.org/kilo/config-reference/content/policy-json-file.html>`_
+
+With this file you can set who may upload packages and perform other operations.
+
+The :file:`policy.json` example is:
+
+.. code-block:: javascript
+
+    {
+       // Rule declaration
+       "context_is_admin": "role:admin",
+       "admin_api": "is_admin:True",
+       "default": "",
+
+       // Package operations
+       "get_package": "rule:default",
+       "upload_package": "rule:default",
+       "modify_package": "rule:default",
+       "publicize_package": "rule:admin_api",
+       "manage_public_package": "rule:default",
+       "delete_package": "rule:default",
+       "download_package": "rule:default",
+
+       // Category operations
+       "get_category": "rule:default",
+       "delete_category": "rule:admin_api",
+       "add_category": "rule:admin_api",
+
+       // Deployment read operations
+       "list_deployments": "rule:default",
+       "statuses_deployments": "rule:default",
+
+       // Environment operations
+       "list_environments": "rule:default",
+       "list_environments_all_tenants": "rule:admin_api",
+       "show_environment": "rule:default",
+       "update_environment": "rule:default",
+       "create_environment": "rule:default",
+       "delete_environment": "rule:default",
+
+       // Environment template operations
+       "list_env_templates": "rule:default",
+       "create_env_template": "rule:default",
+       "show_env_template": "rule:default",
+       "update_env_template": "rule:default",
+       "delete_env_template": "rule:default",
+
+       // Control on executing actions on deployment environments
+       "execute_action": "rule:default"
+    }
+
+So, changing ``"upload_package": "rule:default"`` to ``"rule:admin_api"``
+will forbid regular users to upload packages.
+
+Uploading package wizard in murano dashboard consists of several steps.
+Upload package API call requested from the first form and modify from
+the second one. It provides modifying package parameters on time of
+uploading. So, please modify both configuration together. Otherwise it
+will not be possible to browse package details on the second step
+of the wizard.