/* * Copyright © 2018-2020 A Bunch Tell LLC. * * This file is part of WriteFreely. * * WriteFreely is free software: you can redistribute it and/or modify * it under the terms of the GNU Affero General Public License, included * in the LICENSE file in this source code package. */ package writefreely import ( "database/sql" "fmt" "html/template" "math" "net/http" "strconv" "time" . "github.com/gorilla/feeds" "github.com/gorilla/mux" stripmd "github.com/writeas/go-strip-markdown" "github.com/writeas/impart" "github.com/writeas/web-core/log" "github.com/writeas/web-core/memo" "github.com/writeas/writefreely/page" ) const ( tlFeedLimit = 100 tlAPIPageLimit = 10 tlMaxAuthorPosts = 5 tlPostsPerPage = 16 tlMaxPostCache = 250 tlCacheDur = 10 * time.Minute ) type localTimeline struct { m *memo.Memo posts *[]PublicPost // Configuration values postsPerPage int } type readPublication struct { page.StaticPage Posts *[]PublicPost CurrentPage int TotalPages int SelTopic string IsAdmin bool CanInvite bool // Customizable page content ContentTitle string Content template.HTML } func initLocalTimeline(app *App) { app.timeline = &localTimeline{ postsPerPage: tlPostsPerPage, m: memo.New(app.FetchPublicPosts, tlCacheDur), } } // satisfies memo.Func func (app *App) FetchPublicPosts() (interface{}, error) { // Conditions limit := fmt.Sprintf("LIMIT %d", tlMaxPostCache) // This is better than the hard limit when limiting posts from individual authors // ageCond := `p.created >= ` + app.db.dateSub(3, "month") + ` AND ` // Finds all public posts and posts in a public collection published during the owner's active subscription period and within the last 3 months rows, err := app.db.Query(`SELECT p.id, alias, c.title, p.slug, p.title, p.content, p.text_appearance, p.language, p.rtl, p.created, p.updated FROM collections c LEFT JOIN posts p ON p.collection_id = c.id LEFT JOIN users u ON u.id = p.owner_id WHERE c.privacy = 1 AND (p.created <= ` + app.db.now() + ` AND pinned_position IS NULL) AND u.status = 0 ORDER BY p.created DESC ` + limit) if err != nil { log.Error("Failed selecting from posts: %v", err) return nil, impart.HTTPError{http.StatusInternalServerError, "Couldn't retrieve collection posts." + err.Error()} } defer rows.Close() ap := map[string]uint{} posts := []PublicPost{} for rows.Next() { p := &Post{} c := &Collection{} var alias, title sql.NullString err = rows.Scan(&p.ID, &alias, &title, &p.Slug, &p.Title, &p.Content, &p.Font, &p.Language, &p.RTL, &p.Created, &p.Updated) if err != nil { log.Error("[READ] Unable to scan row, skipping: %v", err) continue } c.hostName = app.cfg.App.Host isCollectionPost := alias.Valid if isCollectionPost { c.Alias = alias.String if c.Alias != "" && ap[c.Alias] == tlMaxAuthorPosts { // Don't add post if we've hit the post-per-author limit continue } c.Public = true c.Title = title.String } p.extractData() p.HTMLContent = template.HTML(applyMarkdown([]byte(p.Content), "", app.cfg)) fp := p.processPost() if isCollectionPost { fp.Collection = &CollectionObj{Collection: *c} } posts = append(posts, fp) ap[c.Alias]++ } return posts, nil } func viewLocalTimelineAPI(app *App, w http.ResponseWriter, r *http.Request) error { updateTimelineCache(app.timeline) skip, _ := strconv.Atoi(r.FormValue("skip")) posts := []PublicPost{} for i := skip; i < skip+tlAPIPageLimit && i < len(*app.timeline.posts); i++ { posts = append(posts, (*app.timeline.posts)[i]) } return impart.WriteSuccess(w, posts, http.StatusOK) } func viewLocalTimeline(app *App, w http.ResponseWriter, r *http.Request) error { if !app.cfg.App.LocalTimeline { return impart.HTTPError{http.StatusNotFound, "Page doesn't exist."} } vars := mux.Vars(r) var p int page := 1 p, _ = strconv.Atoi(vars["page"]) if p > 0 { page = p } return showLocalTimeline(app, w, r, page, vars["author"], vars["tag"]) } func updateTimelineCache(tl *localTimeline) { // Fetch posts if enough time has passed since last cache if tl.posts == nil || tl.m.Invalidate() { log.Info("[READ] Updating post cache") var err error var postsInterfaces interface{} postsInterfaces, err = tl.m.Get() if err != nil { log.Error("[READ] Unable to cache posts: %v", err) } else { castPosts := postsInterfaces.([]PublicPost) tl.posts = &castPosts } } } func showLocalTimeline(app *App, w http.ResponseWriter, r *http.Request, page int, author, tag string) error { updateTimelineCache(app.timeline) pl := len(*(app.timeline.posts)) ttlPages := int(math.Ceil(float64(pl) / float64(app.timeline.postsPerPage))) start := 0 if page > 1 { start = app.timeline.postsPerPage * (page - 1) if start > pl { return impart.HTTPError{http.StatusFound, fmt.Sprintf("/read/p/%d", ttlPages)} } } end := app.timeline.postsPerPage * page if end > pl { end = pl } var posts []PublicPost if author != "" { posts = []PublicPost{} for _, p := range *app.timeline.posts { if author == "anonymous" { if p.Collection == nil { posts = append(posts, p) } } else if p.Collection != nil && p.Collection.Alias == author { posts = append(posts, p) } } } else if tag != "" { posts = []PublicPost{} for _, p := range *app.timeline.posts { if p.HasTag(tag) { posts = append(posts, p) } } } else { posts = *app.timeline.posts posts = posts[start:end] } d := &readPublication{ StaticPage: pageForReq(app, r), Posts: &posts, CurrentPage: page, TotalPages: ttlPages, SelTopic: tag, } if app.cfg.App.Chorus { u := getUserSession(app, r) d.IsAdmin = u != nil && u.IsAdmin() d.CanInvite = canUserInvite(app.cfg, d.IsAdmin) } c, err := getReaderSection(app) if err != nil { return err } d.ContentTitle = c.Title.String d.Content = template.HTML(applyMarkdown([]byte(c.Content), "", app.cfg)) err = templates["read"].ExecuteTemplate(w, "base", d) if err != nil { log.Error("Unable to render reader: %v", err) fmt.Fprintf(w, ":(") } return nil } // NextPageURL provides a full URL for the next page of collection posts func (c *readPublication) NextPageURL(n int) string { return fmt.Sprintf("/read/p/%d", n+1) } // PrevPageURL provides a full URL for the previous page of collection posts, // returning a /page/N result for pages >1 func (c *readPublication) PrevPageURL(n int) string { if n == 2 { // Previous page is 1; no need for /p/ prefix return "/read" } return fmt.Sprintf("/read/p/%d", n-1) } // handlePostIDRedirect handles a route where a post ID is given and redirects // the user to the canonical post URL. func handlePostIDRedirect(app *App, w http.ResponseWriter, r *http.Request) error { vars := mux.Vars(r) postID := vars["post"] p, err := app.db.GetPost(postID, 0) if err != nil { return err } if !p.CollectionID.Valid { // No collection; send to normal URL // NOTE: not handling single user blogs here since this handler is only used for the Reader return impart.HTTPError{http.StatusFound, app.cfg.App.Host + "/" + postID + ".md"} } c, err := app.db.GetCollectionBy("id = ?", fmt.Sprintf("%d", p.CollectionID.Int64)) if err != nil { return err } c.hostName = app.cfg.App.Host // Retrieve collection information and send user to canonical URL return impart.HTTPError{http.StatusFound, c.CanonicalURL() + p.Slug.String} } func viewLocalTimelineFeed(app *App, w http.ResponseWriter, req *http.Request) error { if !app.cfg.App.LocalTimeline { return impart.HTTPError{http.StatusNotFound, "Page doesn't exist."} } updateTimelineCache(app.timeline) feed := &Feed{ Title: app.cfg.App.SiteName + " Reader", Link: &Link{Href: app.cfg.App.Host}, Description: "Read the latest posts from " + app.cfg.App.SiteName + ".", Created: time.Now(), } c := 0 var title, permalink, author string for _, p := range *app.timeline.posts { if c == tlFeedLimit { break } title = p.PlainDisplayTitle() permalink = p.CanonicalURL(app.cfg.App.Host) if p.Collection != nil { author = p.Collection.Title } else { author = "Anonymous" permalink += ".md" } i := &Item{ Id: app.cfg.App.Host + "/read/a/" + p.ID, Title: title, Link: &Link{Href: permalink}, Description: "<![CDATA[" + stripmd.Strip(p.Content) + "]]>", Content: applyMarkdown([]byte(p.Content), "", app.cfg), Author: &Author{author, ""}, Created: p.Created, Updated: p.Updated, } feed.Items = append(feed.Items, i) c++ } rss, err := feed.ToRss() if err != nil { return err } fmt.Fprint(w, rss) return nil }