func (e *GoImageEngine) Transform(img *imagefile.ImageFile, operation *Operation, qs map[string]string) (*imagefile.ImageFile, error) {
params := map[string]string{
"upscale": "1",
"h": "0",
"w": "0",
"deg": "90",
}
err := mergo.Merge(&qs, params)
if err != nil {
return nil, err
}
var quality int
var format string
q, ok := qs["q"]
if ok {
quality, err := strconv.Atoi(q)
if err != nil {
return nil, err
}
if quality > 100 {
return nil, fmt.Errorf("Quality should be <= 100")
}
} else {
quality = e.DefaultQuality
}
format, ok = qs["fmt"]
filepath := img.Filepath
if ok {
if _, ok := ContentTypes[format]; !ok {
return nil, fmt.Errorf("Unknown format %s", format)
}
}
if format == "" && e.Format != "" {
format = e.Format
}
if format == "" {
format = img.Format()
}
if format == "" {
format = e.DefaultFormat
}
if format != img.Format() {
index := len(filepath) - len(img.Format())
filepath = filepath[:index] + format
}
file := &imagefile.ImageFile{
Source: img.Source,
Key: img.Key,
Headers: img.Headers,
Filepath: filepath,
}
options := &Options{
Quality: quality,
Format: Formats[format],
}
switch operation {
case Flip:
pos, ok := qs["pos"]
if !ok {
return nil, fmt.Errorf("Parameter \"pos\" not found in query string")
}
content, err := e.Flip(img, pos, options)
if err != nil {
return nil, err
}
file.Processed = content
return file, err
case Rotate:
deg, err := strconv.Atoi(qs["deg"])
if err != nil {
return nil, err
}
content, err := e.Rotate(img, deg, options)
if err != nil {
return nil, err
}
file.Processed = content
return file, err
case Thumbnail, Resize, Fit:
var upscale bool
var w int
var h int
if upscale, err = strconv.ParseBool(qs["upscale"]); err != nil {
return nil, err
}
if w, err = strconv.Atoi(qs["w"]); err != nil {
return nil, err
}
if h, err = strconv.Atoi(qs["h"]); err != nil {
return nil, err
}
options.Upscale = upscale
switch operation {
case Resize:
content, err := e.Resize(img, w, h, options)
if err != nil {
return nil, err
}
file.Processed = content
return file, err
case Thumbnail:
content, err := e.Thumbnail(img, w, h, options)
if err != nil {
return nil, err
}
file.Processed = content
return file, err
case Fit:
content, err := e.Fit(img, w, h, options)
if err != nil {
return nil, err
}
file.Processed = content
return file, err
}
case Original:
file.Processed = img.Source
return file, err
}
return nil, fmt.Errorf("Operation not found for %s", operation)
}
func (a *Application) ImageFileFromRequest(req *Request, async bool, load bool) (*image.ImageFile, error) {
var file *image.ImageFile = &image.ImageFile{
Key: req.Key,
Storage: a.DestStorage,
Headers: map[string]string{},
}
var err error
key := a.WithPrefix(req.Key)
// Image from the KVStore found
stored, err := gokvstores.String(req.Connection.Get(key))
file.Filepath = stored
if stored != "" {
a.Logger.Infof("Key %s found in kvstore: %s", key, stored)
if load {
file, err = image.FromStorage(a.DestStorage, stored)
if err != nil {
return nil, err
}
}
} else {
a.Logger.Infof("Key %s not found in kvstore", key)
// Image not found from the KVStore, we need to process it
// URL available in Query String
if req.URL != nil {
file, err = image.FromURL(req.URL)
} else {
// URL provided we use http protocol to retrieve it
file, err = image.FromStorage(a.SourceStorage, req.Filepath)
}
if err != nil {
return nil, err
}
file, err = a.Engine.Transform(file, req.Operation, req.QueryString)
if err != nil {
return nil, err
}
file.Filepath = fmt.Sprintf("%s.%s", a.ShardFilename(req.Key), file.Format())
}
file.Key = req.Key
file.Storage = a.DestStorage
file.Headers["Content-Type"] = file.ContentType()
file.Headers["ETag"] = req.Key
if stored == "" {
if async == true {
go a.Store(req.Filepath, file)
} else {
err = a.Store(req.Filepath, file)
}
}
return file, err
}