Restricted users (#6274)

* Restricted users (#4334): initial implementation

* Add User.IsRestricted & UI to edit it

* Pass user object instead of user id to places where IsRestricted flag matters

* Restricted users: maintain access rows for all referenced repos (incl public)

* Take logged in user & IsRestricted flag into account in org/repo listings, searches and accesses

* Add basic repo access tests for restricted users

Signed-off-by: Manush Dodunekov <manush@stendahls.se>

* Mention restricted users in the faq

Signed-off-by: Manush Dodunekov <manush@stendahls.se>

* Revert unnecessary change `.isUserPartOfOrg` -> `.IsUserPartOfOrg`

Signed-off-by: Manush Dodunekov <manush@stendahls.se>

* Remove unnecessary `org.IsOrganization()` call

Signed-off-by: Manush Dodunekov <manush@stendahls.se>

* Revert to an `int64` keyed `accessMap`

* Add type `userAccess`
* Add convenience func updateUserAccess()
* Turn accessMap into a `map[int64]userAccess`

Signed-off-by: Manush Dodunekov <manush@stendahls.se>

* or even better: `map[int64]*userAccess`

* updateUserAccess(): use tighter syntax as suggested by lafriks

* even tighter

* Avoid extra loop

* Don't disclose limited orgs to unauthenticated users

* Don't assume block only applies to orgs

* Use an array of `VisibleType` for filtering

* fix yet another thinko

* Ok - no need for u

* Revert "Ok - no need for u"

This reverts commit 5c3e886aab.

Co-authored-by: Antoine GIRARD <sapk@users.noreply.github.com>
Co-authored-by: Lauris BH <lauris@nix.lv>

models/migrations/migrations.go

@@ -296,6 +296,8 @@ var migrations = []Migration{
 	NewMigration("Fix migrated repositories' git service type", fixMigratedRepositoryServiceType),
 	// v120 -> v121
 	NewMigration("Add owner_name on table repository", addOwnerNameOnRepository),
+	// v121 -> v122
+	NewMigration("add is_restricted column for users table", addIsRestricted),
 }
 
 // Migrate database to current version

models/migrations/v121.go

@@ -0,0 +1,17 @@
+// Copyright 2020 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package migrations
+
+import "xorm.io/xorm"
+
+func addIsRestricted(x *xorm.Engine) error {
+	// User see models/user.go
+	type User struct {
+		ID           int64 `xorm:"pk autoincr"`
+		IsRestricted bool  `xorm:"NOT NULL DEFAULT false"`
+	}
+
+	return x.Sync2(new(User))
+}