Introduce Policies-Service (#5716)

* add policies service
add policies proxy middleware
add policies event service
add policies grpc service
prepare ci and git environments (ci, make, readme, doc)

* add webfinger to the drone conf

* fix docs
remove not used virus scan postprocessing step

* relocate example rego file
implicitly enable and disable proxy and postprocessing policy checking by setting the query.
update configuration descriptions

* move policies
update readme

* use converter func to convert pp environment to actual environment
expose and test custom rego functions
add engine unit tests
add opa unit tests
update policies readme

Co-authored-by: Martin <github@diemattels.at>

* relocate sample policies to the deployments folder
change and document policies service port

* update index.md and small fix

* add health command
add version command
add debug server

---------

Co-authored-by: Martin <github@diemattels.at>

services/proxy/pkg/command/server.go

@@ -199,7 +199,6 @@ func loadMiddlewares(ctx context.Context, logger log.Logger, cfg *config.Config)
 		Logger:            logger,
 		RevaGatewayClient: revaClient,
 	})
-
 	authenticators = append(authenticators, middleware.SignedURLAuthenticator{
 		Logger:             logger,
 		PreSignedURLConfig: cfg.PreSignedURL,
@@ -219,9 +218,7 @@ func loadMiddlewares(ctx context.Context, logger log.Logger, cfg *config.Config)
 			cfg.OIDC.RewriteWellKnown,
 			oidcHTTPClient,
 		),
-
 		router.Middleware(cfg.PolicySelector, cfg.Policies, logger),
-
 		middleware.Authentication(
 			authenticators,
 			middleware.CredentialsByUserAgent(cfg.AuthMiddleware.CredentialsByUserAgent),
@@ -237,13 +234,12 @@ func loadMiddlewares(ctx context.Context, logger log.Logger, cfg *config.Config)
 			middleware.UserCS3Claim(cfg.UserCS3Claim),
 			middleware.AutoprovisionAccounts(cfg.AutoprovisionAccounts),
 		),
-
 		middleware.SelectorCookie(
 			middleware.Logger(logger),
 			middleware.UserProvider(userProvider),
 			middleware.PolicySelectorConfig(*cfg.PolicySelector),
 		),
-
+		middleware.Policies(logger, cfg.PoliciesMiddleware.Query),
 		// finally, trigger home creation when a user logs in
 		middleware.CreateHome(
 			middleware.Logger(logger),