// 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" "fmt" "time" "github.com/gorilla/feeds" "github.com/superseriousbusiness/gotosocial/internal/config" "github.com/superseriousbusiness/gotosocial/internal/db" "github.com/superseriousbusiness/gotosocial/internal/gtserror" "github.com/superseriousbusiness/gotosocial/internal/gtsmodel" ) const ( rssFeedLength = 20 ) type GetRSSFeed func() (string, gtserror.WithCode) // GetRSSFeedForUsername returns a function to return the RSS feed of a local account // with the given username, and the last-modified time (time that the account last // posted a status eligible to be included in the rss feed). // // To save db calls, callers to this function should only call the returned GetRSSFeed // func if the last-modified time is newer than the last-modified time they have cached. // // If the account has not yet posted an RSS-eligible status, the returned last-modified // time will be zero, and the GetRSSFeed func will return a valid RSS xml with no items. func (p *Processor) GetRSSFeedForUsername(ctx context.Context, username string) (GetRSSFeed, time.Time, gtserror.WithCode) { var ( never = time.Time{} ) account, err := p.state.DB.GetAccountByUsernameDomain(ctx, username, "") if err != nil { if errors.Is(err, db.ErrNoEntries) { // Simply no account with this username. err = gtserror.New("account not found") return nil, never, gtserror.NewErrorNotFound(err) } // Real db error. err = gtserror.Newf("db error getting account %s: %w", username, err) return nil, never, gtserror.NewErrorInternalError(err) } // Ensure account has rss feed enabled. if !*account.Settings.EnableRSS { err = gtserror.New("account RSS feed not enabled") return nil, never, gtserror.NewErrorNotFound(err) } // LastModified time is needed by callers to check freshness for cacheing. // This might be a zero time.Time if account has never posted a status that's // eligible to appear in the RSS feed; that's fine. lastPostAt, err := p.state.DB.GetAccountLastPosted(ctx, account.ID, true) if err != nil && !errors.Is(err, db.ErrNoEntries) { err = gtserror.Newf("db error getting account %s last posted: %w", username, err) return nil, never, gtserror.NewErrorInternalError(err) } return func() (string, gtserror.WithCode) { // Assemble author namestring once only. author := "@" + account.Username + "@" + config.GetAccountDomain() // Derive image/thumbnail for this account (may be nil). image, errWithCode := p.rssImageForAccount(ctx, account, author) if errWithCode != nil { return "", errWithCode } feed := &feeds.Feed{ Title: "Posts from " + author, Description: "Posts from " + author, Link: &feeds.Link{Href: account.URL}, Image: image, } // If the account has never posted anything, just use // account creation time as Updated value for the feed; // we could use time.Now() here but this would likely // mess up cacheing; we want something determinate. // // We can also return early rather than wasting a db call, // since we already know there's no eligible statuses. if lastPostAt.IsZero() { feed.Updated = account.CreatedAt return stringifyFeed(feed) } // Account has posted at least one status that's // eligible to appear in the RSS feed. // // Reuse the lastPostAt value for feed.Updated. feed.Updated = lastPostAt // Retrieve latest statuses as they'd be shown on the web view of the account profile. statuses, err := p.state.DB.GetAccountWebStatuses(ctx, account.ID, rssFeedLength, "") if err != nil && !errors.Is(err, db.ErrNoEntries) { err = fmt.Errorf("db error getting account web statuses: %w", err) return "", gtserror.NewErrorInternalError(err) } // Add each status to the rss feed. for _, status := range statuses { item, err := p.converter.StatusToRSSItem(ctx, status) if err != nil { err = gtserror.Newf("error converting status to feed item: %w", err) return "", gtserror.NewErrorInternalError(err) } feed.Add(item) } return stringifyFeed(feed) }, lastPostAt, nil } func (p *Processor) rssImageForAccount(ctx context.Context, account *gtsmodel.Account, author string) (*feeds.Image, gtserror.WithCode) { if account.AvatarMediaAttachmentID == "" { // No image, no problem! return nil, nil } // Ensure account avatar attachment populated. if account.AvatarMediaAttachment == nil { var err error account.AvatarMediaAttachment, err = p.state.DB.GetAttachmentByID(ctx, account.AvatarMediaAttachmentID) if err != nil { if errors.Is(err, db.ErrNoEntries) { // No attachment found with this ID (race condition?). return nil, nil } // Real db error. err = gtserror.Newf("db error fetching avatar media attachment: %w", err) return nil, gtserror.NewErrorInternalError(err) } } return &feeds.Image{ Url: account.AvatarMediaAttachment.Thumbnail.URL, Title: "Avatar for " + author, Link: account.URL, }, nil } func stringifyFeed(feed *feeds.Feed) (string, gtserror.WithCode) { // Stringify the feed. Even with no statuses, // this will still produce valid rss xml. rss, err := feed.ToRss() if err != nil { err := gtserror.Newf("error converting feed to rss string: %w", err) return "", gtserror.NewErrorInternalError(err) } return rss, nil }