gotosocial/internal/media/processingmedia.go

520 lines
15 KiB
Go

// GoToSocial
// Copyright (C) GoToSocial Authors admin@gotosocial.org
// SPDX-License-Identifier: AGPL-3.0-or-later
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
package media
import (
"bytes"
"context"
"errors"
"image/jpeg"
"io"
"time"
errorsv2 "codeberg.org/gruf/go-errors/v2"
"codeberg.org/gruf/go-runners"
"github.com/disintegration/imaging"
"github.com/h2non/filetype"
"github.com/superseriousbusiness/exif-terminator"
"github.com/superseriousbusiness/gotosocial/internal/gtserror"
"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
"github.com/superseriousbusiness/gotosocial/internal/log"
"github.com/superseriousbusiness/gotosocial/internal/storage"
"github.com/superseriousbusiness/gotosocial/internal/uris"
"github.com/superseriousbusiness/gotosocial/internal/util"
)
// ProcessingMedia represents a piece of media
// currently being processed. It exposes functions
// for retrieving data from the process.
type ProcessingMedia struct {
media *gtsmodel.MediaAttachment // processing media attachment details
dataFn DataFunc // load-data function, returns media stream
recache bool // recaching existing (uncached) media
done bool // done is set when process finishes with non ctx canceled type error
proc runners.Processor // proc helps synchronize only a singular running processing instance
err error // error stores permanent error value when done
mgr *Manager // mgr instance (access to db / storage)
}
// AttachmentID returns the ID of the underlying
// media attachment without blocking processing.
func (p *ProcessingMedia) AttachmentID() string {
return p.media.ID // immutable, safe outside mutex.
}
// LoadAttachment blocks until the thumbnail and
// fullsize content has been processed, and then
// returns the attachment.
//
// If processing could not be completed fully
// then an error will be returned. The attachment
// will still be returned in that case, but it will
// only be partially complete and should be treated
// as a placeholder.
func (p *ProcessingMedia) LoadAttachment(ctx context.Context) (*gtsmodel.MediaAttachment, error) {
// Attempt to load synchronously.
media, done, err := p.load(ctx)
if err == nil {
// No issue, return media.
return media, nil
}
if !done {
// Provided context was cancelled,
// e.g. request aborted early before
// its context could be used to finish
// loading the attachment. Enqueue for
// asynchronous processing, which will
// use a background context.
log.Warnf(ctx, "reprocessing media %s after canceled ctx", p.media.ID)
go p.mgr.state.Workers.Media.Enqueue(p.Process)
}
// Media could not be retrieved FULLY,
// but partial attachment should be present.
return media, err
}
// Process allows the receiving object to fit the
// runners.WorkerFunc signature. It performs a
// (blocking) load and logs on error.
func (p *ProcessingMedia) Process(ctx context.Context) {
if _, _, err := p.load(ctx); err != nil {
log.Errorf(ctx, "error(s) processing media: %v", err)
}
}
// load performs a concurrency-safe load of ProcessingMedia, only
// marking itself as complete when returned error is NOT a context cancel.
func (p *ProcessingMedia) load(ctx context.Context) (*gtsmodel.MediaAttachment, bool, error) {
var (
done bool
err error
)
err = p.proc.Process(func() error {
if p.done {
// Already proc'd.
return p.err
}
defer func() {
// This is only done when ctx NOT cancelled.
done = err == nil || !errorsv2.IsV2(err,
context.Canceled,
context.DeadlineExceeded,
)
if !done {
return
}
// Store final values.
p.done = true
p.err = err
}()
// Gather errors as we proceed.
var errs = gtserror.NewMultiError(4)
// Attempt to store media and calculate
// full-size media attachment details.
//
// This will update p.media as it goes.
storeErr := p.store(ctx)
if storeErr != nil {
errs.Append(storeErr)
}
// Finish processing by reloading media into
// memory to get dimension and generate a thumb.
//
// This will update p.media as it goes.
if finishErr := p.finish(ctx); finishErr != nil {
errs.Append(finishErr)
}
// If this isn't a file we were able to process,
// we may have partially stored it (eg., it's a
// jpeg, which is fine, but streaming it to storage
// was interrupted halfway through and so it was
// never decoded). Try to clean up in this case.
if p.media.Type == gtsmodel.FileTypeUnknown {
deleteErr := p.mgr.state.Storage.Delete(ctx, p.media.File.Path)
if deleteErr != nil && !errors.Is(deleteErr, storage.ErrNotFound) {
errs.Append(deleteErr)
}
}
var dbErr error
switch {
case !p.recache:
// First time caching this attachment, insert it.
dbErr = p.mgr.state.DB.PutAttachment(ctx, p.media)
case p.recache && len(errs) == 0:
// Existing attachment we're recaching, update it.
//
// (We only want to update if everything went OK so far,
// otherwise we'd better leave previous version alone.)
dbErr = p.mgr.state.DB.UpdateAttachment(ctx, p.media)
}
if dbErr != nil {
errs.Append(dbErr)
}
err = errs.Combine()
return err
})
return p.media, done, err
}
// store calls the data function attached to p if it hasn't been called yet,
// and updates the underlying attachment fields as necessary. It will then stream
// bytes from p's reader directly into storage so that it can be retrieved later.
func (p *ProcessingMedia) store(ctx context.Context) error {
// Load media from provided data fun
rc, sz, err := p.dataFn(ctx)
if err != nil {
return gtserror.Newf("error executing data function: %w", err)
}
defer func() {
// Ensure data reader gets closed on return.
if err := rc.Close(); err != nil {
log.Errorf(ctx, "error closing data reader: %v", err)
}
}()
// Assume we're given correct file
// size, we can overwrite this later
// once we know THE TRUTH.
fileSize := int(sz)
p.media.File.FileSize = fileSize
// Prepare to read bytes from
// file header or magic number.
hdrBuf := newHdrBuf(fileSize)
// Read into buffer as much as possible.
//
// UnexpectedEOF means we couldn't read up to the
// given size, but we may still have read something.
//
// EOF means we couldn't read anything at all.
//
// Any other error likely means the connection messed up.
//
// In other words, rather counterintuitively, we
// can only proceed on no error or unexpected error!
n, err := io.ReadFull(rc, hdrBuf)
if err != nil {
if err != io.ErrUnexpectedEOF {
return gtserror.Newf("error reading first bytes of incoming media: %w", err)
}
// Initial file size was misreported, so we didn't read
// fully into hdrBuf. Reslice it to the size we did read.
log.Warnf(ctx,
"recovered from misreported file size; reported %d; read %d",
fileSize, n,
)
hdrBuf = hdrBuf[:n]
fileSize = n
p.media.File.FileSize = fileSize
}
// Parse file type info from header buffer.
// This should only ever error if the buffer
// is empty (ie., the attachment is 0 bytes).
info, err := filetype.Match(hdrBuf)
if err != nil {
return gtserror.Newf("error parsing file type: %w", err)
}
// Recombine header bytes with remaining stream
r := io.MultiReader(bytes.NewReader(hdrBuf), rc)
// Assume we'll put
// this file in storage.
store := true
switch info.Extension {
case "mp4":
// No problem.
case "gif":
// No problem
case "jpg", "jpeg", "png", "webp":
if fileSize > 0 {
// A file size was provided so we can clean
// exif data from image as we're streaming it.
r, err = terminator.Terminate(r, fileSize, info.Extension)
if err != nil {
return gtserror.Newf("error cleaning exif data: %w", err)
}
}
default:
// The file is not a supported format that
// we can process, so we can't do much with it.
log.Warnf(ctx,
"media extension '%s' not officially supported, will be processed as "+
"type '%s' with minimal metadata, and will not be cached locally",
info.Extension, gtsmodel.FileTypeUnknown,
)
// Don't bother storing this.
store = false
}
// Fill in correct attachment
// data now we're parsed it.
p.media.URL = uris.URIForAttachment(
p.media.AccountID,
string(TypeAttachment),
string(SizeOriginal),
p.media.ID,
info.Extension,
)
// Prefer discovered mime type, fall back to
// generic "this contains some bytes" type.
mime := info.MIME.Value
if mime == "" {
mime = "application/octet-stream"
}
p.media.File.ContentType = mime
// Calculate attachment file path.
p.media.File.Path = uris.StoragePathForAttachment(
p.media.AccountID,
string(TypeAttachment),
string(SizeOriginal),
p.media.ID,
info.Extension,
)
// We should only try to store the file if it's
// a format we can keep processing, otherwise be
// a bit cheeky: don't store it and let users
// click through to the remote server instead.
if !store {
return nil
}
// File shouldn't already exist in storage at this point,
// but we do a check as it's worth logging / cleaning up.
if have, _ := p.mgr.state.Storage.Has(ctx, p.media.File.Path); have {
log.Warnf(ctx, "media already exists at storage path: %s", p.media.File.Path)
// Attempt to remove existing media at storage path (might be broken / out-of-date)
if err := p.mgr.state.Storage.Delete(ctx, p.media.File.Path); err != nil {
return gtserror.Newf("error removing media from storage: %v", err)
}
}
// Write the final reader stream to our storage.
wroteSize, err := p.mgr.state.Storage.PutStream(ctx, p.media.File.Path, r)
if err != nil {
return gtserror.Newf("error writing media to storage: %w", err)
}
// Set actual written size
// as authoritative file size.
p.media.File.FileSize = int(wroteSize)
// We can now consider this cached.
p.media.Cached = util.Ptr(true)
return nil
}
func (p *ProcessingMedia) finish(ctx context.Context) error {
// Make a jolly assumption about thumbnail type.
p.media.Thumbnail.ContentType = mimeImageJpeg
// Calculate attachment thumbnail file path
p.media.Thumbnail.Path = uris.StoragePathForAttachment(
p.media.AccountID,
string(TypeAttachment),
string(SizeSmall),
p.media.ID,
// Always encode attachment
// thumbnails as jpg.
"jpg",
)
// Calculate attachment thumbnail serve path.
p.media.Thumbnail.URL = uris.URIForAttachment(
p.media.AccountID,
string(TypeAttachment),
string(SizeSmall),
p.media.ID,
// Always encode attachment
// thumbnails as jpg.
"jpg",
)
// If original file hasn't been stored, there's
// likely something wrong with the data, or we
// don't want to store it. Skip everything else.
if !*p.media.Cached {
p.media.Processing = gtsmodel.ProcessingStatusProcessed
return nil
}
// Get a stream to the original file for further processing.
rc, err := p.mgr.state.Storage.GetStream(ctx, p.media.File.Path)
if err != nil {
return gtserror.Newf("error loading file from storage: %w", err)
}
defer rc.Close()
// fullImg is the processed version of
// the original (stripped + reoriented).
var fullImg *gtsImage
// Depending on the content type, we
// can do various types of decoding.
switch p.media.File.ContentType {
// .jpeg, .gif, .webp image type
case mimeImageJpeg, mimeImageGif, mimeImageWebp:
fullImg, err = decodeImage(
rc,
imaging.AutoOrientation(true),
)
if err != nil {
return gtserror.Newf("error decoding image: %w", err)
}
// Mark as no longer unknown type now
// we know for sure we can decode it.
p.media.Type = gtsmodel.FileTypeImage
// .png image (requires ancillary chunk stripping)
case mimeImagePng:
fullImg, err = decodeImage(
&pngAncillaryChunkStripper{Reader: rc},
imaging.AutoOrientation(true),
)
if err != nil {
return gtserror.Newf("error decoding image: %w", err)
}
// Mark as no longer unknown type now
// we know for sure we can decode it.
p.media.Type = gtsmodel.FileTypeImage
// .mp4 video type
case mimeVideoMp4:
video, err := decodeVideoFrame(rc)
if err != nil {
return gtserror.Newf("error decoding video: %w", err)
}
// Set video frame as image.
fullImg = video.frame
// Set video metadata in attachment info.
p.media.FileMeta.Original.Duration = &video.duration
p.media.FileMeta.Original.Framerate = &video.framerate
p.media.FileMeta.Original.Bitrate = &video.bitrate
// Mark as no longer unknown type now
// we know for sure we can decode it.
p.media.Type = gtsmodel.FileTypeVideo
}
// fullImg should be in-memory by
// now so we're done with storage.
if err := rc.Close(); err != nil {
return gtserror.Newf("error closing file: %w", err)
}
// Set full-size dimensions in attachment info.
p.media.FileMeta.Original.Width = int(fullImg.Width())
p.media.FileMeta.Original.Height = int(fullImg.Height())
p.media.FileMeta.Original.Size = int(fullImg.Size())
p.media.FileMeta.Original.Aspect = fullImg.AspectRatio()
// Get smaller thumbnail image
thumbImg := fullImg.Thumbnail()
// Garbage collector, you may
// now take our large son.
fullImg = nil
// Only generate blurhash
// from thumb if necessary.
if p.media.Blurhash == "" {
hash, err := thumbImg.Blurhash()
if err != nil {
return gtserror.Newf("error generating blurhash: %w", err)
}
// Set the attachment blurhash.
p.media.Blurhash = hash
}
// Thumbnail shouldn't already exist in storage at this point,
// but we do a check as it's worth logging / cleaning up.
if have, _ := p.mgr.state.Storage.Has(ctx, p.media.Thumbnail.Path); have {
log.Warnf(ctx, "thumbnail already exists at storage path: %s", p.media.Thumbnail.Path)
// Attempt to remove existing thumbnail at storage path (might be broken / out-of-date)
if err := p.mgr.state.Storage.Delete(ctx, p.media.Thumbnail.Path); err != nil {
return gtserror.Newf("error removing thumbnail from storage: %v", err)
}
}
// Create a thumbnail JPEG encoder stream.
enc := thumbImg.ToJPEG(&jpeg.Options{
// Good enough for
// a thumbnail.
Quality: 70,
})
// Stream-encode the JPEG thumbnail image into storage.
sz, err := p.mgr.state.Storage.PutStream(ctx, p.media.Thumbnail.Path, enc)
if err != nil {
return gtserror.Newf("error stream-encoding thumbnail to storage: %w", err)
}
// Set thumbnail dimensions in attachment info.
p.media.FileMeta.Small = gtsmodel.Small{
Width: int(thumbImg.Width()),
Height: int(thumbImg.Height()),
Size: int(thumbImg.Size()),
Aspect: thumbImg.AspectRatio(),
}
// Set written image size.
p.media.Thumbnail.FileSize = int(sz)
// Finally set the attachment as processed and update time.
p.media.Processing = gtsmodel.ProcessingStatusProcessed
p.media.File.UpdatedAt = time.Now()
return nil
}