Federated user activity following: Isolated model changes (#8078)

This PR is part of https://codeberg.org/forgejo/forgejo/pulls/4767

This should not have an outside impact but bring all model changes needed & bring migrations.

Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/8078
Reviewed-by: Earl Warren <earl-warren@noreply.codeberg.org>
Co-authored-by: Michael Jerger <michael.jerger@meissa-gmbh.de>
Co-committed-by: Michael Jerger <michael.jerger@meissa-gmbh.de>

models/user/user_repository.go

@@ -1,4 +1,4 @@
-// Copyright 2024 The Forgejo Authors. All rights reserved.
+// Copyright 2024, 2025 The Forgejo Authors. All rights reserved.
 // SPDX-License-Identifier: MIT
 
 package user
@@ -8,12 +8,14 @@ import (
 	"fmt"
 
 	"forgejo.org/models/db"
+	"forgejo.org/modules/log"
 	"forgejo.org/modules/optional"
 	"forgejo.org/modules/validation"
 )
 
 func init() {
 	db.RegisterModel(new(FederatedUser))
+	db.RegisterModel(new(FederatedUserFollower))
 }
 
 func CreateFederatedUser(ctx context.Context, user *User, federatedUser *FederatedUser) error {
@@ -30,7 +32,12 @@ func CreateFederatedUser(ctx context.Context, user *User, federatedUser *Federat
 	if err != nil {
 		return err
 	}
-	defer committer.Close()
+	defer func() {
+		err := committer.Close()
+		if err != nil {
+			log.Error("Error closing committer: %v", err)
+		}
+	}()
 
 	if err := CreateUser(ctx, user, &overwrite); err != nil {
 		return err
@@ -50,6 +57,14 @@ func CreateFederatedUser(ctx context.Context, user *User, federatedUser *Federat
 	return committer.Commit()
 }
 
+func (federatedUser *FederatedUser) UpdateFederatedUser(ctx context.Context) error {
+	if _, err := validation.IsValid(federatedUser); err != nil {
+		return err
+	}
+	_, err := db.GetEngine(ctx).ID(federatedUser.ID).Cols("inbox_path").Update(federatedUser)
+	return err
+}
+
 func FindFederatedUser(ctx context.Context, externalID string, federationHostID int64) (*User, *FederatedUser, error) {
 	federatedUser := new(FederatedUser)
 	user := new(User)
@@ -75,6 +90,41 @@ func FindFederatedUser(ctx context.Context, externalID string, federationHostID
 	return user, federatedUser, nil
 }
 
+func GetFederatedUser(ctx context.Context, externalID string, federationHostID int64) (*User, *FederatedUser, error) {
+	user, federatedUser, err := FindFederatedUser(ctx, externalID, federationHostID)
+	if err != nil {
+		return nil, nil, err
+	} else if federatedUser == nil {
+		return nil, nil, fmt.Errorf("FederatedUser for externalId = %v and federationHostId = %v does not exist", externalID, federationHostID)
+	}
+	return user, federatedUser, nil
+}
+
+func GetFederatedUserByUserID(ctx context.Context, userID int64) (*User, *FederatedUser, error) {
+	federatedUser := new(FederatedUser)
+	user := new(User)
+	has, err := db.GetEngine(ctx).Where("user_id=?", userID).Get(federatedUser)
+	if err != nil {
+		return nil, nil, err
+	} else if !has {
+		return nil, nil, fmt.Errorf("Federated user %v does not exist", federatedUser.UserID)
+	}
+	has, err = db.GetEngine(ctx).ID(federatedUser.UserID).Get(user)
+	if err != nil {
+		return nil, nil, err
+	} else if !has {
+		return nil, nil, fmt.Errorf("User %v for federated user is missing", federatedUser.UserID)
+	}
+
+	if res, err := validation.IsValid(*user); !res {
+		return nil, nil, err
+	}
+	if res, err := validation.IsValid(*federatedUser); !res {
+		return nil, nil, err
+	}
+	return user, federatedUser, nil
+}
+
 func FindFederatedUserByKeyID(ctx context.Context, keyID string) (*User, *FederatedUser, error) {
 	federatedUser := new(FederatedUser)
 	user := new(User)
@@ -101,7 +151,85 @@ func FindFederatedUserByKeyID(ctx context.Context, keyID string) (*User, *Federa
 	return user, federatedUser, nil
 }
 
+func UpdateFederatedUser(ctx context.Context, federatedUser *FederatedUser) error {
+	if res, err := validation.IsValid(federatedUser); !res {
+		return err
+	}
+	_, err := db.GetEngine(ctx).ID(federatedUser.ID).Update(federatedUser)
+	return err
+}
+
 func DeleteFederatedUser(ctx context.Context, userID int64) error {
 	_, err := db.GetEngine(ctx).Delete(&FederatedUser{UserID: userID})
 	return err
 }
+
+func GetFollowersForUser(ctx context.Context, user *User) ([]*FederatedUserFollower, error) {
+	if res, err := validation.IsValid(user); !res {
+		return nil, err
+	}
+	followers := make([]*FederatedUserFollower, 0, 8)
+
+	err := db.GetEngine(ctx).
+		Where("followed_user_id = ?", user.ID).
+		Find(&followers)
+	if err != nil {
+		return nil, err
+	}
+	for _, element := range followers {
+		if res, err := validation.IsValid(*element); !res {
+			return nil, err
+		}
+	}
+	return followers, nil
+}
+
+func AddFollower(ctx context.Context, followedUser *User, followingUser *FederatedUser) (*FederatedUserFollower, error) {
+	if res, err := validation.IsValid(followedUser); !res {
+		return nil, err
+	}
+	if res, err := validation.IsValid(followingUser); !res {
+		return nil, err
+	}
+
+	federatedUserFollower, err := NewFederatedUserFollower(followedUser.ID, followingUser.UserID)
+	if err != nil {
+		return nil, err
+	}
+	_, err = db.GetEngine(ctx).Insert(&federatedUserFollower)
+	if err != nil {
+		return nil, err
+	}
+
+	return &federatedUserFollower, err
+}
+
+func RemoveFollower(ctx context.Context, followedUser *User, followingUser *FederatedUser) error {
+	if res, err := validation.IsValid(followedUser); !res {
+		return err
+	}
+	if res, err := validation.IsValid(followingUser); !res {
+		return err
+	}
+
+	_, err := db.GetEngine(ctx).Delete(&FederatedUserFollower{
+		FollowedUserID:  followedUser.ID,
+		FollowingUserID: followingUser.UserID,
+	})
+	return err
+}
+
+// TODO: We should unify Activity-pub-following and classical following (see models/user/follow.go)
+func IsFollowingAp(ctx context.Context, followedUser *User, followingUser *FederatedUser) (bool, error) {
+	if res, err := validation.IsValid(followedUser); !res {
+		return false, err
+	}
+	if res, err := validation.IsValid(followingUser); !res {
+		return false, err
+	}
+
+	return db.GetEngine(ctx).Get(&FederatedUserFollower{
+		FollowedUserID:  followedUser.ID,
+		FollowingUserID: followingUser.UserID,
+	})
+}