[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

3 files changed, 23 insertions, 9 deletions

diff --git a/internal/federation/dereferencing/emoji.go b/internal/federation/dereferencing/emoji.go
index 16f5acf25..806a3f5ee 100644
--- a/internal/federation/dereferencing/emoji.go
+++ b/internal/federation/dereferencing/emoji.go
@@ -23,6 +23,7 @@ import (
 	"io"
 	"net/url"
 
+	"github.com/superseriousbusiness/gotosocial/internal/config"
 	"github.com/superseriousbusiness/gotosocial/internal/db"
 	"github.com/superseriousbusiness/gotosocial/internal/gtserror"
 	"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
@@ -90,9 +91,12 @@ func (d *Dereferencer) GetEmoji(
 		return nil, err
 	}
 
+	// Get maximum supported remote emoji size.
+	maxsz := config.GetMediaEmojiRemoteMaxSize()
+
 	// Prepare data function to dereference remote emoji media.
-	data := func(context.Context) (io.ReadCloser, int64, error) {
-		return tsport.DereferenceMedia(ctx, url)
+	data := func(context.Context) (io.ReadCloser, error) {
+		return tsport.DereferenceMedia(ctx, url, int64(maxsz))
 	}
 
 	// Pass along for safe processing.
@@ -171,9 +175,12 @@ func (d *Dereferencer) RefreshEmoji(
 		return nil, err
 	}
 
+	// Get maximum supported remote emoji size.
+	maxsz := config.GetMediaEmojiRemoteMaxSize()
+
 	// Prepare data function to dereference remote emoji media.
-	data := func(context.Context) (io.ReadCloser, int64, error) {
-		return tsport.DereferenceMedia(ctx, url)
+	data := func(context.Context) (io.ReadCloser, error) {
+		return tsport.DereferenceMedia(ctx, url, int64(maxsz))
 	}
 
 	// Pass along for safe processing.
diff --git a/internal/federation/dereferencing/emoji_test.go b/internal/federation/dereferencing/emoji_test.go
index fdb815762..12965207c 100644
--- a/internal/federation/dereferencing/emoji_test.go
+++ b/internal/federation/dereferencing/emoji_test.go
@@ -75,7 +75,7 @@ func (suite *EmojiTestSuite) TestDereferenceEmojiBlocking() {
 	suite.Equal("image/gif", emoji.ImageContentType)
 	suite.Equal("image/png", emoji.ImageStaticContentType)
 	suite.Equal(37796, emoji.ImageFileSize)
-	suite.Equal(7951, emoji.ImageStaticFileSize)
+	suite.Equal(9824, emoji.ImageStaticFileSize)
 	suite.WithinDuration(time.Now(), emoji.UpdatedAt, 10*time.Second)
 	suite.False(*emoji.Disabled)
 	suite.Equal(emojiURI, emoji.URI)
diff --git a/internal/federation/dereferencing/media.go b/internal/federation/dereferencing/media.go
index 874107b13..956866e94 100644
--- a/internal/federation/dereferencing/media.go
+++ b/internal/federation/dereferencing/media.go
@@ -22,6 +22,7 @@ import (
 	"io"
 	"net/url"
 
+	"github.com/superseriousbusiness/gotosocial/internal/config"
 	"github.com/superseriousbusiness/gotosocial/internal/gtserror"
 	"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
 	"github.com/superseriousbusiness/gotosocial/internal/media"
@@ -69,12 +70,15 @@ func (d *Dereferencer) GetMedia(
 		return nil, gtserror.Newf("failed getting transport for %s: %w", requestUser, err)
 	}
 
+	// Get maximum supported remote media size.
+	maxsz := config.GetMediaRemoteMaxSize()
+
 	// Start processing remote attachment at URL.
 	processing, err := d.mediaManager.CreateMedia(
 		ctx,
 		accountID,
-		func(ctx context.Context) (io.ReadCloser, int64, error) {
-			return tsport.DereferenceMedia(ctx, url)
+		func(ctx context.Context) (io.ReadCloser, error) {
+			return tsport.DereferenceMedia(ctx, url, int64(maxsz))
 		},
 		info,
 	)
@@ -163,11 +167,14 @@ func (d *Dereferencer) RefreshMedia(
 		return nil, gtserror.Newf("failed getting transport for %s: %w", requestUser, err)
 	}
 
+	// Get maximum supported remote media size.
+	maxsz := config.GetMediaRemoteMaxSize()
+
 	// Start processing remote attachment recache.
 	processing := d.mediaManager.RecacheMedia(
 		media,
-		func(ctx context.Context) (io.ReadCloser, int64, error) {
-			return tsport.DereferenceMedia(ctx, url)
+		func(ctx context.Context) (io.ReadCloser, error) {
+			return tsport.DereferenceMedia(ctx, url, int64(maxsz))
 		},
 	)