// Theme handler builds an image with the colors of a theme // the theme is defined by keyword :theme // url: "/themes/:theme" func Theme(w http.ResponseWriter, r *http.Request) { var err error var th string if th, _ = route.Context.Get(r, "theme"); err != nil { th = "base" } colorMap := colors.MapOfColorThemes() var theme []color.RGBA if val, ok := colorMap[th]; ok { theme = val } else { theme = colorMap["base"] } width := extract.WidthOrDefault(r, 20*len(theme)) height := extract.HeightOrDefault(r, 34) if f := extract.Format(r); f == format.JPEG { m := image.NewRGBA(image.Rect(0, 0, width, height)) squares.Palette(m, theme) var img image.Image = m write.ImageJPEG(w, &img) } else if f == format.SVG { write.ImageSVG(w) squares.PaletteSVG(w, theme, width, height) } }
// BannerRandomGradient handler for "/squares/banner/random/gradient" // generates a random banner grid image with gradient colors from brighter to darker color. func BannerRandomGradient(w http.ResponseWriter, r *http.Request) { width := extract.Width(r) height := extract.Height(r) xsquares := extract.XSquares(r) colors := extract.Colors(r) if f := extract.Format(r); f == format.JPEG { m := image.NewRGBA(image.Rect(0, 0, width, height)) squares.RandomGradientGrid(m, colors, xsquares) var img image.Image = m write.ImageJPEG(w, &img) } else if f == format.SVG { write.ImageSVG(w) squares.RandomGradientGridSVG(w, colors, width, height, xsquares) } }
// Random handler for "/squares/random" // generates a random 6 by 6 grid image. func Random(w http.ResponseWriter, r *http.Request) { size := extract.Size(r) colors := extract.Colors(r) prob := extract.Probability(r, 1/float64(len(colors))) if f := extract.Format(r); f == format.JPEG { m := image.NewRGBA(image.Rect(0, 0, size, size)) squares.RandomGrid(m, colors, 6, prob) var img image.Image = m write.ImageJPEG(w, &img) } else if f == format.SVG { write.ImageSVG(w) squares.RandomGridSVG(w, colors, size, size, 6, prob) } }
// BannerRandom handler for "/squares/banner/random" // generates a random banner grid image. func BannerRandom(w http.ResponseWriter, r *http.Request) { width := extract.Width(r) height := extract.Height(r) xsquares := extract.XSquares(r) colors := extract.Colors(r) prob := extract.Probability(r, 1/float64(len(colors))) if f := extract.Format(r); f == format.JPEG { m := image.NewRGBA(image.Rect(0, 0, width, height)) squares.RandomGrid(m, colors, xsquares, prob) var img image.Image = m write.ImageJPEG(w, &img) } else if f == format.SVG { write.ImageSVG(w) squares.RandomGridSVG(w, colors, width, height, xsquares, prob) } }
// Checkerboard is the handler for /checkerboard // build a 6x6 checkerboard with alternate black and white colors. func Checkerboard(w http.ResponseWriter, r *http.Request) { size := extract.Size(r) theme := extract.Theme(r) colorMap := colors.MapOfColorThemes() var c1, c2 color.RGBA if val, ok := colorMap[theme]; ok { c1 = val[0] c2 = val[1] } else { c1 = colorMap["base"][0] c2 = colorMap["base"][1] } if f := extract.Format(r); f == format.JPEG { m := image.NewRGBA(image.Rect(0, 0, size, size)) squares.Grid(m, c1, c2) var img image.Image = m write.ImageJPEG(w, &img) } else if f == format.SVG { write.ImageSVG(w) squares.GridSVG(w, c1, c2, size) } }
// Square handler for /squares/:key // builds a 6 by 6 grid with alternate colors based the key passed in the url. func Square(w http.ResponseWriter, r *http.Request) { var err error var key string if key, err = route.Context.Get(r, "key"); err != nil { log.Println("Unable to get 'key' value: ", err) key = "" } theme := extract.Theme(r) h := md5.New() io.WriteString(h, key) key = fmt.Sprintf("%x", h.Sum(nil)[:]) e := `"` + theme + key + `"` w.Header().Set("Etag", e) w.Header().Set("Cache-Control", "max-age=2592000") // 30 days if match := r.Header.Get("If-None-Match"); match != "" { if strings.Contains(match, e) { w.WriteHeader(http.StatusNotModified) return } } colors := extract.Colors(r) size := extract.Size(r) if f := extract.Format(r); f == format.JPEG { m := image.NewRGBA(image.Rect(0, 0, size, size)) squares.Image(m, key, colors) var img image.Image = m write.ImageJPEG(w, &img) } else if f == format.SVG { write.ImageSVG(w) squares.SVG(w, key, colors, size) } }