resize

Dockerfile

@@ -1,21 +1,14 @@
 FROM golang:latest
-
-MAINTAINER Andreas Neue <an@dnix.de>
-
 RUN apt -y update && \
     apt -y upgrade && \
     apt -y install libglib2.0-dev libexpat1-dev libjpeg-dev libpng-dev libgif-dev
-
 WORKDIR /go/src/image-resizer
 COPY . .
-
 RUN wget https://github.com/libvips/libvips/releases/download/v8.7.3/vips-8.7.3.tar.gz && \
     tar xvzf vips-8.7.3.tar.gz && \
     cd vips-8.7.3 && \
     ./configure && \
     make && \
     make install && \
-    go get -v -u github.com/davidbyttow/govips/pkg/vips && \
+    ldconfig
-    go install -v ./...
+RUN go get -v -u github.com/davidbyttow/govips/pkg/vips && go install -v ./...
-
-CMD ["image-resizer", "-s", "https://images.example.com/"]

main.go

@@ -22,6 +22,83 @@ func init() {
 	flag.Parse()
 }
 
+func resizeHandler(w http.ResponseWriter, r *http.Request) {
+	// Get the query parameters from the request URL
+	path := r.URL.EscapedPath()
+	parm := strings.Split(path, "/")
+	if len(parm) < 4 {
+		writeError(w, "", "", "error in arguments", http.StatusBadRequest)
+		return
+	}
+
+	method := parm[1]
+	args := parm[2]
+	imgPath := strings.Join(parm[3:], "/")
+
+	// Start fetching the image from the given url
+	resp, err := http.Get(*imgServer + imgPath)
+	if err != nil {
+		writeError(w, imgPath, method, "failed to fetch image", http.StatusNotFound)
+		return
+	}
+	defer resp.Body.Close()
+
+	switch method {
+	case "resize":
+		size := strings.Split(args, "x")
+		if len(size) < 2 {
+			writeError(w, imgPath, method, "url, width, and height are required", http.StatusBadRequest)
+			return
+		}
+		width := size[0]
+		height := size[1]
+
+		// Validate that all three required fields are present
+		if imgPath == "" || width == "" || height == "" {
+			writeError(w, imgPath, method, "url, width, and height are required", http.StatusBadRequest)
+			return
+		}
+
+		// Convert width and height to integers
+		iw, errW := strconv.Atoi(width)
+		ih, errH := strconv.Atoi(height)
+		if errW != nil || errH != nil {
+			writeError(w, imgPath, method, "width and height must be integers", http.StatusBadRequest)
+			return
+		}
+
+		// Ensure that a valid response was given
+		if resp.StatusCode/100 != 2 {
+			writeError(w, imgPath, method, fmt.Sprintf("failed to fetch image (%v)", resp.StatusCode), http.StatusBadRequest)
+			return
+		}
+
+		// govips returns the output of the image as a []byte object. We don't need
+		// it since we are directly piping it to the ResponseWriter
+		_, _, err = vips.NewTransform().
+			Load(resp.Body).
+			ResizeStrategy(vips.ResizeStrategyEmbed).
+			Resize(iw, ih).
+			Output(w).
+			Apply()
+
+		if err != nil {
+			writeError(w, imgPath, method, "failed to resize", http.StatusInternalServerError)
+			return
+		}
+
+	default:
+		writeError(w, imgPath, method, "unknown method", http.StatusBadRequest)
+		return
+	}
+
+}
+
+func writeError(w http.ResponseWriter, imgPath, method, err string, status int) {
+	w.WriteHeader(status)
+	w.Write([]byte(fmt.Sprintf("Error [%s %s]: %s", method, imgPath, err)))
+}
+
 func main() {
 	// Start vips with the default configuration
 	vips.Startup(nil)
@@ -30,70 +107,3 @@ func main() {
 	http.HandleFunc("/", resizeHandler)
 	log.Fatal(http.ListenAndServe(*listenAddr, nil))
 }
-
-func resizeHandler(w http.ResponseWriter, r *http.Request) {
-	// Get the query parameters from the request URL
-	path := r.URL.EscapedPath()
-	parm := strings.Split(path, "/")
-	if len(parm) < 3 {
-		w.Write([]byte(fmt.Sprintf("url, width and height are required")))
-		w.WriteHeader(http.StatusBadRequest)
-		return
-	}
-	queryUrl := parm[2]
-	size := strings.Split(parm[1], "x")
-	if len(size) < 2 {
-		w.Write([]byte(fmt.Sprintf("url, width and height are required")))
-		w.WriteHeader(http.StatusBadRequest)
-		return
-	}
-	queryWidth := size[0]
-	queryHeight := size[1]
-
-	// Validate that all three required fields are present
-	if queryUrl == "" || queryWidth == "" || queryHeight == "" {
-		w.Write([]byte(fmt.Sprintf("url, width and height are required")))
-		w.WriteHeader(http.StatusBadRequest)
-		return
-	}
-
-	// Convert width and height to integers
-	width, errW := strconv.Atoi(queryWidth)
-	height, errH := strconv.Atoi(queryHeight)
-	if errW != nil || errH != nil {
-		w.Write([]byte(fmt.Sprintf("width and height must be integers")))
-		w.WriteHeader(http.StatusBadRequest)
-		return
-	}
-
-	// Start fetching the image from the given url
-	resp, err := http.Get(*imgServer + queryUrl)
-	if err != nil {
-		w.Write([]byte(fmt.Sprintf("failed to get %s: %v", queryUrl, err)))
-		w.WriteHeader(http.StatusBadRequest)
-		return
-	}
-
-	// Ensure that a valid response was given
-	if resp.StatusCode/100 != 2 {
-		w.Write([]byte(fmt.Sprintf("failed to get %s: status %d", queryUrl, resp.StatusCode)))
-		w.WriteHeader(http.StatusBadRequest)
-		return
-	}
-	defer resp.Body.Close()
-
-	// govips returns the output of the image as a []byte object. We don't need
-	// it since we are directly piping it to the ResponseWriter
-	_, _, err = vips.NewTransform().
-		Load(resp.Body).
-		ResizeStrategy(vips.ResizeStrategyStretch).
-		Resize(width, height).
-		Output(w).
-		Apply()
-
-	if err != nil {
-		w.Write([]byte(fmt.Sprintf("failed to resize %s: %v", queryUrl, err)))
-		w.WriteHeader(http.StatusInternalServerError)
-		return
-	}
-}