gotosocial/internal/processing/account/follow.go

304 lines
11 KiB
Go

// GoToSocial
// Copyright (C) GoToSocial Authors admin@gotosocial.org
// SPDX-License-Identifier: AGPL-3.0-or-later
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
package account
import (
"context"
"errors"
"github.com/superseriousbusiness/gotosocial/internal/ap"
apimodel "github.com/superseriousbusiness/gotosocial/internal/api/model"
"github.com/superseriousbusiness/gotosocial/internal/db"
"github.com/superseriousbusiness/gotosocial/internal/gtscontext"
"github.com/superseriousbusiness/gotosocial/internal/gtserror"
"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
"github.com/superseriousbusiness/gotosocial/internal/id"
"github.com/superseriousbusiness/gotosocial/internal/messages"
"github.com/superseriousbusiness/gotosocial/internal/uris"
)
// FollowCreate handles a follow request to an account, either remote or local.
func (p *Processor) FollowCreate(ctx context.Context, requestingAccount *gtsmodel.Account, form *apimodel.AccountFollowRequest) (*apimodel.Relationship, gtserror.WithCode) {
targetAccount, errWithCode := p.getFollowTarget(ctx, requestingAccount, form.ID)
if errWithCode != nil {
return nil, errWithCode
}
// Check if a follow exists already.
if follow, err := p.state.DB.GetFollow(
gtscontext.SetBarebones(ctx),
requestingAccount.ID,
targetAccount.ID,
); err != nil && !errors.Is(err, db.ErrNoEntries) {
err = gtserror.Newf("db error checking existing follow: %w", err)
return nil, gtserror.NewErrorInternalError(err)
} else if follow != nil {
// Already follows, update if necessary + return relationship.
return p.updateFollow(
ctx,
requestingAccount,
form,
follow.ShowReblogs,
follow.Notify,
func(columns ...string) error { return p.state.DB.UpdateFollow(ctx, follow, columns...) },
)
}
// Check if a follow request exists already.
if followRequest, err := p.state.DB.GetFollowRequest(
gtscontext.SetBarebones(ctx),
requestingAccount.ID,
targetAccount.ID,
); err != nil && !errors.Is(err, db.ErrNoEntries) {
err = gtserror.Newf("db error checking existing follow request: %w", err)
return nil, gtserror.NewErrorInternalError(err)
} else if followRequest != nil {
// Already requested, update if necessary + return relationship.
return p.updateFollow(
ctx,
requestingAccount,
form,
followRequest.ShowReblogs,
followRequest.Notify,
func(columns ...string) error { return p.state.DB.UpdateFollowRequest(ctx, followRequest, columns...) },
)
}
// Neither follows nor follow requests, so
// create and store a new follow request.
followID, err := id.NewRandomULID()
if err != nil {
return nil, gtserror.NewErrorInternalError(err)
}
followURI := uris.GenerateURIForFollow(requestingAccount.Username, followID)
fr := &gtsmodel.FollowRequest{
ID: followID,
URI: followURI,
AccountID: requestingAccount.ID,
Account: requestingAccount,
TargetAccountID: form.ID,
TargetAccount: targetAccount,
ShowReblogs: form.Reblogs,
Notify: form.Notify,
}
if err := p.state.DB.PutFollowRequest(ctx, fr); err != nil {
err = gtserror.Newf("error creating follow request in db: %s", err)
return nil, gtserror.NewErrorInternalError(err)
}
if targetAccount.IsLocal() && !*targetAccount.Locked {
// If the target account is local and not locked,
// we can already accept the follow request and
// skip any further processing.
//
// Because we know the requestingAccount is also
// local, we don't need to federate the accept out.
if _, err := p.state.DB.AcceptFollowRequest(ctx, requestingAccount.ID, form.ID); err != nil {
err = gtserror.Newf("error accepting follow request for local unlocked account: %w", err)
return nil, gtserror.NewErrorInternalError(err)
}
} else if targetAccount.IsRemote() {
// Otherwise we leave the follow request as it is,
// and we handle the rest of the process async.
p.state.Workers.EnqueueClientAPI(ctx, messages.FromClientAPI{
APObjectType: ap.ActivityFollow,
APActivityType: ap.ActivityCreate,
GTSModel: fr,
OriginAccount: requestingAccount,
TargetAccount: targetAccount,
})
}
return p.RelationshipGet(ctx, requestingAccount, form.ID)
}
// FollowRemove handles the removal of a follow/follow request to an account, either remote or local.
func (p *Processor) FollowRemove(ctx context.Context, requestingAccount *gtsmodel.Account, targetAccountID string) (*apimodel.Relationship, gtserror.WithCode) {
targetAccount, errWithCode := p.getFollowTarget(ctx, requestingAccount, targetAccountID)
if errWithCode != nil {
return nil, errWithCode
}
// Unfollow and deal with side effects.
msgs, err := p.unfollow(ctx, requestingAccount, targetAccount)
if err != nil {
return nil, gtserror.NewErrorNotFound(gtserror.Newf("account %s not found in the db: %s", targetAccountID, err))
}
// Batch queue accreted client api messages.
p.state.Workers.EnqueueClientAPI(ctx, msgs...)
return p.RelationshipGet(ctx, requestingAccount, targetAccountID)
}
/*
Utility functions.
*/
// updateFollow is a utility function for updating an existing
// follow or followRequest with the parameters provided in the
// given form. If nothing changes, this function is a no-op and
// will just return the existing relationship between follow
// origin and follow target account.
func (p *Processor) updateFollow(
ctx context.Context,
requestingAccount *gtsmodel.Account,
form *apimodel.AccountFollowRequest,
currentShowReblogs *bool,
currentNotify *bool,
update func(...string) error,
) (*apimodel.Relationship, gtserror.WithCode) {
if form.Reblogs == nil && form.Notify == nil {
// There's nothing to update.
return p.RelationshipGet(ctx, requestingAccount, form.ID)
}
// Including "updated_at", max 3 columns may change.
columns := make([]string, 0, 3)
// Check what we need to update (if anything).
if newReblogs := form.Reblogs; newReblogs != nil && *newReblogs != *currentShowReblogs {
*currentShowReblogs = *newReblogs
columns = append(columns, "show_reblogs")
}
if newNotify := form.Notify; newNotify != nil && *newNotify != *currentNotify {
*currentNotify = *newNotify
columns = append(columns, "notify")
}
if len(columns) == 0 {
// Nothing actually changed.
return p.RelationshipGet(ctx, requestingAccount, form.ID)
}
if err := update(columns...); err != nil {
err = gtserror.Newf("error updating existing follow (request): %w", err)
return nil, gtserror.NewErrorInternalError(err)
}
return p.RelationshipGet(ctx, requestingAccount, form.ID)
}
// getFollowTarget is a convenience function which:
// - Checks if account is trying to follow/unfollow itself.
// - Returns not found if target should not be visible to requester.
// - Returns target account according to its id.
func (p *Processor) getFollowTarget(ctx context.Context, requester *gtsmodel.Account, targetID string) (*gtsmodel.Account, gtserror.WithCode) {
// Check for requester.
if requester == nil {
err := errors.New("no authorized user")
return nil, gtserror.NewErrorUnauthorized(err)
}
// Account can't follow or unfollow itself.
if requester.ID == targetID {
err := errors.New("account can't follow or unfollow itself")
return nil, gtserror.NewErrorNotAcceptable(err)
}
// Fetch the target account for requesting user account.
return p.c.GetVisibleTargetAccount(ctx, requester, targetID)
}
// unfollow is a convenience function for having requesting account
// unfollow (and un follow request) target account, if follows and/or
// follow requests exist.
//
// If a follow and/or follow request was removed this way, one or two
// messages will be returned which should then be processed by a client
// api worker.
func (p *Processor) unfollow(ctx context.Context, requestingAccount *gtsmodel.Account, targetAccount *gtsmodel.Account) ([]messages.FromClientAPI, error) {
var msgs []messages.FromClientAPI
// Get follow from requesting account to target account.
follow, err := p.state.DB.GetFollow(ctx, requestingAccount.ID, targetAccount.ID)
if err != nil && !errors.Is(err, db.ErrNoEntries) {
err = gtserror.Newf("error getting follow from %s targeting %s: %w", requestingAccount.ID, targetAccount.ID, err)
return nil, err
}
if follow != nil {
// Delete known follow from database with ID.
err = p.state.DB.DeleteFollowByID(ctx, follow.ID)
if err != nil {
if !errors.Is(err, db.ErrNoEntries) {
err = gtserror.Newf("error deleting request from %s targeting %s: %w", requestingAccount.ID, targetAccount.ID, err)
return nil, err
}
// If err == db.ErrNoEntries here then it
// indicates a race condition with another
// unfollow for the same requester->target.
return msgs, nil
}
// Follow status changed, process side effects.
msgs = append(msgs, messages.FromClientAPI{
APObjectType: ap.ActivityFollow,
APActivityType: ap.ActivityUndo,
GTSModel: &gtsmodel.Follow{
AccountID: requestingAccount.ID,
TargetAccountID: targetAccount.ID,
URI: follow.URI,
},
OriginAccount: requestingAccount,
TargetAccount: targetAccount,
})
}
// Get follow request from requesting account to target account.
followReq, err := p.state.DB.GetFollowRequest(ctx, requestingAccount.ID, targetAccount.ID)
if err != nil && !errors.Is(err, db.ErrNoEntries) {
err = gtserror.Newf("error getting follow request from %s targeting %s: %w", requestingAccount.ID, targetAccount.ID, err)
return nil, err
}
if followReq != nil {
// Delete known follow request from database with ID.
err = p.state.DB.DeleteFollowRequestByID(ctx, followReq.ID)
if err != nil {
if !errors.Is(err, db.ErrNoEntries) {
err = gtserror.Newf("error deleting follow request from %s targeting %s: %w", requestingAccount.ID, targetAccount.ID, err)
return nil, err
}
// If err == db.ErrNoEntries here then it
// indicates a race condition with another
// unfollow for the same requester->target.
return msgs, nil
}
// Follow status changed, process side effects.
msgs = append(msgs, messages.FromClientAPI{
APObjectType: ap.ActivityFollow,
APActivityType: ap.ActivityUndo,
GTSModel: &gtsmodel.Follow{
AccountID: requestingAccount.ID,
TargetAccountID: targetAccount.ID,
URI: followReq.URI,
},
OriginAccount: requestingAccount,
TargetAccount: targetAccount,
})
}
return msgs, nil
}