dendrite/mediaapi/thumbnailer/thumbnailer_nfnt.go
Andrew Morgan bc382bba46
Fix pipeline, emoji and syntax (#713)
Fixes #697

Switched to golangci-lint, fixes issues with buildkite and does some linting fixes to appease the new linters.
2019-06-19 14:05:03 +01:00

272 lines
7.8 KiB
Go

// Copyright 2017 Vector Creations Ltd
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// +build !bimg
package thumbnailer
import (
"context"
"image"
"image/draw"
// Imported for gif codec
_ "image/gif"
"image/jpeg"
// Imported for png codec
_ "image/png"
"os"
"time"
"github.com/matrix-org/dendrite/common/config"
"github.com/matrix-org/dendrite/mediaapi/storage"
"github.com/matrix-org/dendrite/mediaapi/types"
"github.com/nfnt/resize"
log "github.com/sirupsen/logrus"
)
// GenerateThumbnails generates the configured thumbnail sizes for the source file
func GenerateThumbnails(
ctx context.Context,
src types.Path,
configs []config.ThumbnailSize,
mediaMetadata *types.MediaMetadata,
activeThumbnailGeneration *types.ActiveThumbnailGeneration,
maxThumbnailGenerators int,
db *storage.Database,
logger *log.Entry,
) (busy bool, errorReturn error) {
img, err := readFile(string(src))
if err != nil {
logger.WithError(err).WithField("src", src).Error("Failed to read src file")
return false, err
}
for _, singleConfig := range configs {
// Note: createThumbnail does locking based on activeThumbnailGeneration
busy, err = createThumbnail(
ctx, src, img, types.ThumbnailSize(singleConfig), mediaMetadata,
activeThumbnailGeneration, maxThumbnailGenerators, db, logger,
)
if err != nil {
logger.WithError(err).WithField("src", src).Error("Failed to generate thumbnails")
return false, err
}
if busy {
return true, nil
}
}
return false, nil
}
// GenerateThumbnail generates the configured thumbnail size for the source file
func GenerateThumbnail(
ctx context.Context,
src types.Path,
config types.ThumbnailSize,
mediaMetadata *types.MediaMetadata,
activeThumbnailGeneration *types.ActiveThumbnailGeneration,
maxThumbnailGenerators int,
db *storage.Database,
logger *log.Entry,
) (busy bool, errorReturn error) {
img, err := readFile(string(src))
if err != nil {
logger.WithError(err).WithFields(log.Fields{
"src": src,
}).Error("Failed to read src file")
return false, err
}
// Note: createThumbnail does locking based on activeThumbnailGeneration
busy, err = createThumbnail(
ctx, src, img, config, mediaMetadata, activeThumbnailGeneration,
maxThumbnailGenerators, db, logger,
)
if err != nil {
logger.WithError(err).WithFields(log.Fields{
"src": src,
}).Error("Failed to generate thumbnails")
return false, err
}
if busy {
return true, nil
}
return false, nil
}
func readFile(src string) (image.Image, error) {
file, err := os.Open(src)
if err != nil {
return nil, err
}
defer file.Close() // nolint: errcheck
img, _, err := image.Decode(file)
if err != nil {
return nil, err
}
return img, nil
}
func writeFile(img image.Image, dst string) (err error) {
out, err := os.Create(dst)
if err != nil {
return err
}
defer (func() { err = out.Close() })()
return jpeg.Encode(out, img, &jpeg.Options{
Quality: 85,
})
}
// createThumbnail checks if the thumbnail exists, and if not, generates it
// Thumbnail generation is only done once for each non-existing thumbnail.
func createThumbnail(
ctx context.Context,
src types.Path,
img image.Image,
config types.ThumbnailSize,
mediaMetadata *types.MediaMetadata,
activeThumbnailGeneration *types.ActiveThumbnailGeneration,
maxThumbnailGenerators int,
db *storage.Database,
logger *log.Entry,
) (busy bool, errorReturn error) {
logger = logger.WithFields(log.Fields{
"Width": config.Width,
"Height": config.Height,
"ResizeMethod": config.ResizeMethod,
})
// Check if request is larger than original
if config.Width >= img.Bounds().Dx() && config.Height >= img.Bounds().Dy() {
return false, nil
}
dst := GetThumbnailPath(src, config)
// Note: getActiveThumbnailGeneration uses mutexes and conditions from activeThumbnailGeneration
isActive, busy, err := getActiveThumbnailGeneration(dst, config, activeThumbnailGeneration, maxThumbnailGenerators, logger)
if err != nil {
return false, err
}
if busy {
return true, nil
}
if isActive {
// Note: This is an active request that MUST broadcastGeneration to wake up waiting goroutines!
// Note: broadcastGeneration uses mutexes and conditions from activeThumbnailGeneration
defer func() {
// Note: errorReturn is the named return variable so we wrap this in a closure to re-evaluate the arguments at defer-time
// if err := recover(); err != nil {
// broadcastGeneration(dst, activeThumbnailGeneration, config, err.(error), logger)
// panic(err)
// }
broadcastGeneration(dst, activeThumbnailGeneration, config, errorReturn, logger)
}()
}
exists, err := isThumbnailExists(ctx, dst, config, mediaMetadata, db, logger)
if err != nil || exists {
return false, err
}
start := time.Now()
width, height, err := adjustSize(dst, img, config.Width, config.Height, config.ResizeMethod == types.Crop, logger)
if err != nil {
return false, err
}
logger.WithFields(log.Fields{
"ActualWidth": width,
"ActualHeight": height,
"processTime": time.Since(start),
}).Info("Generated thumbnail")
stat, err := os.Stat(string(dst))
if err != nil {
return false, err
}
thumbnailMetadata := &types.ThumbnailMetadata{
MediaMetadata: &types.MediaMetadata{
MediaID: mediaMetadata.MediaID,
Origin: mediaMetadata.Origin,
// Note: the code currently always creates a JPEG thumbnail
ContentType: types.ContentType("image/jpeg"),
FileSizeBytes: types.FileSizeBytes(stat.Size()),
},
ThumbnailSize: types.ThumbnailSize{
Width: config.Width,
Height: config.Height,
ResizeMethod: config.ResizeMethod,
},
}
err = db.StoreThumbnail(ctx, thumbnailMetadata)
if err != nil {
logger.WithError(err).WithFields(log.Fields{
"ActualWidth": width,
"ActualHeight": height,
}).Error("Failed to store thumbnail metadata in database.")
return false, err
}
return false, nil
}
// adjustSize scales an image to fit within the provided width and height
// If the source aspect ratio is different to the target dimensions, one edge will be smaller than requested
// If crop is set to true, the image will be scaled to fill the width and height with any excess being cropped off
func adjustSize(dst types.Path, img image.Image, w, h int, crop bool, logger *log.Entry) (int, int, error) {
var out image.Image
var err error
if crop {
inAR := float64(img.Bounds().Dx()) / float64(img.Bounds().Dy())
outAR := float64(w) / float64(h)
var scaleW, scaleH uint
if inAR > outAR {
// input has shorter AR than requested output so use requested height and calculate width to match input AR
scaleW = uint(float64(h) * inAR)
scaleH = uint(h)
} else {
// input has taller AR than requested output so use requested width and calculate height to match input AR
scaleW = uint(w)
scaleH = uint(float64(w) / inAR)
}
scaled := resize.Resize(scaleW, scaleH, img, resize.Lanczos3)
xoff := (scaled.Bounds().Dx() - w) / 2
yoff := (scaled.Bounds().Dy() - h) / 2
tr := image.Rect(0, 0, w, h)
target := image.NewRGBA(tr)
draw.Draw(target, tr, scaled, image.Pt(xoff, yoff), draw.Src)
out = target
} else {
out = resize.Thumbnail(uint(w), uint(h), img, resize.Lanczos3)
}
if err = writeFile(out, string(dst)); err != nil {
logger.WithError(err).Error("Failed to encode and write image")
return -1, -1, err
}
return out.Bounds().Max.X, out.Bounds().Max.Y, nil
}