gitlab-org--gitlab-foss/workhorse/cmd/gitlab-resize-image/main.go

44 lines
975 B
Go

package main
import (
"fmt"
"image"
"os"
"strconv"
"github.com/disintegration/imaging"
"gitlab.com/gitlab-org/gitlab-workhorse/cmd/gitlab-resize-image/png"
)
func main() {
if err := _main(); err != nil {
fmt.Fprintf(os.Stderr, "%s: fatal: %v\n", os.Args[0], err)
os.Exit(1)
}
}
func _main() error {
widthParam := os.Getenv("GL_RESIZE_IMAGE_WIDTH")
requestedWidth, err := strconv.Atoi(widthParam)
if err != nil {
return fmt.Errorf("GL_RESIZE_IMAGE_WIDTH: %w", err)
}
pngReader, err := png.NewReader(os.Stdin)
if err != nil {
return fmt.Errorf("construct PNG reader: %w", err)
}
src, formatName, err := image.Decode(pngReader)
if err != nil {
return fmt.Errorf("decode: %w", err)
}
imagingFormat, err := imaging.FormatFromExtension(formatName)
if err != nil {
return fmt.Errorf("find imaging format: %w", err)
}
image := imaging.Resize(src, requestedWidth, 0, imaging.Lanczos)
return imaging.Encode(os.Stdout, image, imagingFormat)
}