This commit is contained in:
an 2019-01-13 21:09:53 +01:00
parent 271590f775
commit 34817456b1
2 changed files with 79 additions and 76 deletions

View File

@ -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 && \
go install -v ./...
CMD ["image-resizer", "-s", "https://images.example.com/"]
ldconfig
RUN go get -v -u github.com/davidbyttow/govips/pkg/vips && go install -v ./...

144
main.go
View File

@ -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
}
}