package main import ( "bytes" "embed" "encoding/base64" "fmt" "html/template" "log" "math" "net/http" "os" "regexp" "strconv" "strings" "time" "github.com/ChimeraCoder/anaconda" strip "github.com/grokify/html-strip-tags-go" "github.com/joho/godotenv" "github.com/rivo/uniseg" emoji "github.com/tmdvs/Go-Emoji-Utils" ) //go:embed index.html tweet.svg.tmpl suspendedTweet.svg var content embed.FS var ( api *anaconda.TwitterApi tweetDateLayout = "Mon Jan 2 15:04:05 -0700 2006" port string accessToken string accessTokenSecret string consumerKey string consumerSecret string ) func init() { godotenv.Load(os.Getenv("DOTENV_DIR") + ".env") port = os.Getenv("PORT") accessToken = os.Getenv("ACCESS_TOKEN") accessTokenSecret = os.Getenv("ACCESS_TOKEN_SECRET") consumerKey = os.Getenv("CONSUMER_KEY") consumerSecret = os.Getenv("CONSUMER_SECRET") } func main() { if accessToken == "" || accessTokenSecret == "" || consumerKey == "" || consumerSecret == "" { panic("Missing Twitter credentials") } api = anaconda.NewTwitterApiWithCredentials(accessToken, accessTokenSecret, consumerKey, consumerSecret) if port == "" { port = "8080" } http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) { if len(r.URL.Path) > 1 { getTweet(w, r) } else { body, _ := content.ReadFile("index.html") w.Write(body) } }) fmt.Println("Server started at port " + port) log.Fatal(http.ListenAndServe(":"+port, nil)) } func getTweet(w http.ResponseWriter, r *http.Request) { id := strings.ReplaceAll(r.URL.Path, "/", "") i, err := strconv.ParseInt(id, 10, 64) if err != nil { w.WriteHeader(400) return } tweet, err := api.GetTweet(i, nil) if err != nil { switch err := err.(type) { case *anaconda.ApiError: switch err.Decoded.Errors[0].Code { case 63: fmt.Printf("Generating suspended tweet image for %s\n", id) suspendedTweet(w) return } } fmt.Println(err) w.WriteHeader(404) return } processTweet(&tweet) w.Header().Set("Content-type", "image/svg+xml") _, err = w.Write(renderTemplate(tweet, false)) if err != nil { fmt.Println(err) w.WriteHeader(500) return } } func processTweet(tweet *anaconda.Tweet) { gr := uniseg.NewGraphemes(tweet.FullText) count := 0 displayText := "" for gr.Next() { if count >= tweet.DisplayTextRange[0] && count < tweet.DisplayTextRange[1] { displayText += gr.Str() } count += 1 } tweet.FullText = displayText for _, user := range tweet.Entities.User_mentions { tweet.FullText = strings.ReplaceAll(tweet.FullText, "@"+user.Screen_name, fmt.Sprintf("@%s", user.Screen_name, user.Screen_name)) } for _, url := range tweet.Entities.Urls { tweet.FullText = strings.ReplaceAll(tweet.FullText, url.Url, fmt.Sprintf("%s", url.Expanded_url, url.Display_url)) } for _, hashtag := range tweet.Entities.Hashtags { tweet.FullText = strings.ReplaceAll(tweet.FullText, "#"+hashtag.Text, fmt.Sprintf("#%s", hashtag.Text, hashtag.Text)) } tweet.FullText = strings.ReplaceAll(tweet.FullText, "\n", "
") if tweet.QuotedStatus != nil { processTweet(tweet.QuotedStatus) } } func renderTemplate(tweet anaconda.Tweet, isQuoted bool) []byte { templateFuncs := template.FuncMap{ "base64": func(url string) string { res, err := http.Get(url) if err != nil { return "" } buf := new(bytes.Buffer) buf.ReadFrom(res.Body) return base64.StdEncoding.EncodeToString(buf.Bytes()) }, "isoDate": func(date string) string { t, _ := time.Parse(tweetDateLayout, date) return t.Format(time.RFC3339) }, "humanDate": func(date string) string { t, _ := time.Parse(tweetDateLayout, date) return t.Format("3:04 PM ยท Jan 2, 2006") }, "html": func(in string) template.HTML { return template.HTML(in) }, "calculateHeight": func(tweet anaconda.Tweet) string { return fmt.Sprintf("%dpx", calculateHeight(tweet)) }, "renderTweet": func(tweet anaconda.Tweet) template.HTML { return template.HTML(string(renderTemplate(tweet, true))) }, "tweetWidth": func() string { if isQuoted { return "450px" } return "499px" }, "className": func() string { if isQuoted { return "subtweet" } return "tweetsvg" }, } t := template.Must( template.New("tweet.svg.tmpl"). Funcs(templateFuncs). ParseFS(content, "tweet.svg.tmpl")) var buf bytes.Buffer t.Execute(&buf, tweet) return buf.Bytes() } func calculateHeight(tweet anaconda.Tweet) int64 { height := 64.0 /* Avatar */ + 20 /* footer */ + 46 /* text margin */ + 22 /* margin */ lineWidth := 0.0 lineHeight := 28.0 tweetText := strings.ReplaceAll(tweet.FullText, "
", " \n") tweetText = strip.StripTags(tweetText) words := regexp.MustCompile(`[ |-]`).Split(tweetText, -1) for _, word := range words { if len(emoji.FindAll(word)) > 0 { lineHeight = 32.0 } if strings.Contains(word, "\n") { height += lineHeight lineHeight = 28.0 lineWidth = 0 continue } chars := strings.Split(word, "") wordWidth := 0.0 for _, char := range chars { wordWidth += getCharWidth(char) } if wordWidth > 435 { height += (lineHeight * (math.Ceil(wordWidth/435) + 1)) lineHeight = 28.0 lineWidth = 0 } else if lineWidth+getCharWidth(" ")+wordWidth > 435 { height += lineHeight lineHeight = 28.0 lineWidth = wordWidth } else { lineWidth += wordWidth } } if lineWidth > 0 { height += lineHeight } if tweet.InReplyToScreenName != "" { height += 42 } for i, img := range tweet.ExtendedEntities.Media { ratio := float64(img.Sizes.Small.W) / 468 tweet.ExtendedEntities.Media[i].Sizes.Small.W = 468 tweet.ExtendedEntities.Media[i].Sizes.Small.H = int((float64(img.Sizes.Small.H) / ratio) + 5.0) } if len(tweet.ExtendedEntities.Media) > 1 { for i, img := range tweet.ExtendedEntities.Media { tweet.ExtendedEntities.Media[i].Sizes.Small.W = (img.Sizes.Small.W / 2) - 20 tweet.ExtendedEntities.Media[i].Sizes.Small.H = (img.Sizes.Small.H / 2) - 20 } } switch len(tweet.ExtendedEntities.Media) { case 1: height += float64(tweet.ExtendedEntities.Media[0].Sizes.Small.H) case 2: height += math.Max(float64(tweet.ExtendedEntities.Media[0].Sizes.Small.H), float64(tweet.ExtendedEntities.Media[1].Sizes.Small.H)) + 5 case 3: height += math.Max(float64(tweet.ExtendedEntities.Media[0].Sizes.Small.H), float64(tweet.ExtendedEntities.Media[1].Sizes.Small.H)) + 5 height += float64(tweet.ExtendedEntities.Media[2].Sizes.Small.H) + 35 case 4: height += math.Max(float64(tweet.ExtendedEntities.Media[0].Sizes.Small.H), float64(tweet.ExtendedEntities.Media[1].Sizes.Small.H)) + 10 height += math.Max(float64(tweet.ExtendedEntities.Media[2].Sizes.Small.H), float64(tweet.ExtendedEntities.Media[3].Sizes.Small.H)) + 10 height += 7 } if tweet.QuotedStatus != nil { height += float64(calculateHeight(*tweet.QuotedStatus)) + 9 } return int64(height) } func suspendedTweet(w http.ResponseWriter) { w.Header().Set("Content-type", "image/svg+xml") tweet, _ := content.ReadFile("suspendedTweet.svg") w.Write(tweet) }