[feature] support processing of (many) more media types (#3090)

* initial work replacing our media decoding / encoding pipeline with ffprobe + ffmpeg

* specify the video codec to use when generating static image from emoji

* update go-storage library (fixes incompatibility after updating go-iotools)

* maintain image aspect ratio when generating a thumbnail for it

* update readme to show go-ffmpreg

* fix a bunch of media tests, move filesize checking to callers of media manager for more flexibility

* remove extra debug from error message

* fix up incorrect function signatures

* update PutFile to just use regular file copy, as changes are file is on separate partition

* fix remaining tests, remove some unneeded tests now we're working with ffmpeg/ffprobe

* update more tests, add more code comments

* add utilities to generate processed emoji / media outputs

* fix remaining tests

* add test for opus media file, add license header to utility cmds

* limit the number of concurrently available ffmpeg / ffprobe instances

* reduce number of instances

* further reduce number of instances

* fix envparsing test with configuration variables

* update docs and configuration with new media-{local,remote}-max-size variables

1 files changed, 35 insertions, 15 deletions

diff --git a/internal/processing/account/update.go b/internal/processing/account/update.go
index ba9360c36..fda871bd5 100644
--- a/internal/processing/account/update.go
+++ b/internal/processing/account/update.go
@@ -24,7 +24,7 @@ import (
 	"io"
 	"mime/multipart"
 
-	"codeberg.org/gruf/go-bytesize"
+	"codeberg.org/gruf/go-iotools"
 	"github.com/superseriousbusiness/gotosocial/internal/ap"
 	apimodel "github.com/superseriousbusiness/gotosocial/internal/api/model"
 	"github.com/superseriousbusiness/gotosocial/internal/config"
@@ -365,21 +365,31 @@ func (p *Processor) UpdateAvatar(
 	*gtsmodel.MediaAttachment,
 	gtserror.WithCode,
 ) {
-	max := config.GetMediaImageMaxSize()
-	if sz := bytesize.Size(avatar.Size); sz > max {
-		text := fmt.Sprintf("size %s exceeds max media size %s", sz, max)
+	// Get maximum supported local media size.
+	maxsz := config.GetMediaLocalMaxSize()
+
+	// Ensure media within size bounds.
+	if avatar.Size > int64(maxsz) {
+		text := fmt.Sprintf("media exceeds configured max size: %s", maxsz)
 		return nil, gtserror.NewErrorBadRequest(errors.New(text), text)
 	}
 
-	data := func(_ context.Context) (io.ReadCloser, int64, error) {
-		f, err := avatar.Open()
-		return f, avatar.Size, err
+	// Open multipart file reader.
+	mpfile, err := avatar.Open()
+	if err != nil {
+		err := gtserror.Newf("error opening multipart file: %w", err)
+		return nil, gtserror.NewErrorInternalError(err)
 	}
 
+	// Wrap the multipart file reader to ensure is limited to max.
+	rc, _, _ := iotools.UpdateReadCloserLimit(mpfile, int64(maxsz))
+
 	// Write to instance storage.
 	return p.c.StoreLocalMedia(ctx,
 		account.ID,
-		data,
+		func(ctx context.Context) (reader io.ReadCloser, err error) {
+			return rc, nil
+		},
 		media.AdditionalMediaInfo{
 			Avatar:      util.Ptr(true),
 			Description: description,
@@ -400,21 +410,31 @@ func (p *Processor) UpdateHeader(
 	*gtsmodel.MediaAttachment,
 	gtserror.WithCode,
 ) {
-	max := config.GetMediaImageMaxSize()
-	if sz := bytesize.Size(header.Size); sz > max {
-		text := fmt.Sprintf("size %s exceeds max media size %s", sz, max)
+	// Get maximum supported local media size.
+	maxsz := config.GetMediaLocalMaxSize()
+
+	// Ensure media within size bounds.
+	if header.Size > int64(maxsz) {
+		text := fmt.Sprintf("media exceeds configured max size: %s", maxsz)
 		return nil, gtserror.NewErrorBadRequest(errors.New(text), text)
 	}
 
-	data := func(_ context.Context) (io.ReadCloser, int64, error) {
-		f, err := header.Open()
-		return f, header.Size, err
+	// Open multipart file reader.
+	mpfile, err := header.Open()
+	if err != nil {
+		err := gtserror.Newf("error opening multipart file: %w", err)
+		return nil, gtserror.NewErrorInternalError(err)
 	}
 
+	// Wrap the multipart file reader to ensure is limited to max.
+	rc, _, _ := iotools.UpdateReadCloserLimit(mpfile, int64(maxsz))
+
 	// Write to instance storage.
 	return p.c.StoreLocalMedia(ctx,
 		account.ID,
-		data,
+		func(ctx context.Context) (reader io.ReadCloser, err error) {
+			return rc, nil
+		},
 		media.AdditionalMediaInfo{
 			Header:      util.Ptr(true),
 			Description: description,