[bugfix] Wrap media in read closer (#941)

* use readcloser for content.Content

* call media postdata function no matter what

* return a readcloser from data func

* tidy of logic of readertostore

* fix whoopsie

5 files changed, 20 insertions, 29 deletions

diff --git a/internal/processing/account/update.go b/internal/processing/account/update.go
index f39361c06..2ef3bfe25 100644
--- a/internal/processing/account/update.go
+++ b/internal/processing/account/update.go
@@ -192,7 +192,7 @@ func (p *processor) UpdateAvatar(ctx context.Context, avatar *multipart.FileHead
 		return nil, fmt.Errorf("UpdateAvatar: avatar with size %d exceeded max image size of %d bytes", avatar.Size, maxImageSize)
 	}
 
-	dataFunc := func(innerCtx context.Context) (io.Reader, int64, error) {
+	dataFunc := func(innerCtx context.Context) (io.ReadCloser, int64, error) {
 		f, err := avatar.Open()
 		return f, avatar.Size, err
 	}
@@ -219,7 +219,7 @@ func (p *processor) UpdateHeader(ctx context.Context, header *multipart.FileHead
 		return nil, fmt.Errorf("UpdateHeader: header with size %d exceeded max image size of %d bytes", header.Size, maxImageSize)
 	}
 
-	dataFunc := func(innerCtx context.Context) (io.Reader, int64, error) {
+	dataFunc := func(innerCtx context.Context) (io.ReadCloser, int64, error) {
 		f, err := header.Open()
 		return f, header.Size, err
 	}
diff --git a/internal/processing/admin/createemoji.go b/internal/processing/admin/createemoji.go
index 93ae17496..a315e144e 100644
--- a/internal/processing/admin/createemoji.go
+++ b/internal/processing/admin/createemoji.go
@@ -52,7 +52,7 @@ func (p *processor) EmojiCreate(ctx context.Context, account *gtsmodel.Account,
 
 	emojiURI := uris.GenerateURIForEmoji(emojiID)
 
-	data := func(innerCtx context.Context) (io.Reader, int64, error) {
+	data := func(innerCtx context.Context) (io.ReadCloser, int64, error) {
 		f, err := form.Image.Open()
 		return f, form.Image.Size, err
 	}
diff --git a/internal/processing/media/create.go b/internal/processing/media/create.go
index eb0c251e9..451a77391 100644
--- a/internal/processing/media/create.go
+++ b/internal/processing/media/create.go
@@ -30,7 +30,7 @@ import (
 )
 
 func (p *processor) Create(ctx context.Context, account *gtsmodel.Account, form *apimodel.AttachmentRequest) (*apimodel.Attachment, gtserror.WithCode) {
-	data := func(innerCtx context.Context) (io.Reader, int64, error) {
+	data := func(innerCtx context.Context) (io.ReadCloser, int64, error) {
 		f, err := form.File.Open()
 		return f, form.File.Size, err
 	}
diff --git a/internal/processing/media/getfile.go b/internal/processing/media/getfile.go
index 693b8685b..522d47435 100644
--- a/internal/processing/media/getfile.go
+++ b/internal/processing/media/getfile.go
@@ -29,6 +29,7 @@ import (
 	apimodel "github.com/superseriousbusiness/gotosocial/internal/api/model"
 	"github.com/superseriousbusiness/gotosocial/internal/gtserror"
 	"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
+	"github.com/superseriousbusiness/gotosocial/internal/log"
 	"github.com/superseriousbusiness/gotosocial/internal/media"
 	"github.com/superseriousbusiness/gotosocial/internal/uris"
 )
@@ -139,7 +140,7 @@ func (p *processor) getAttachmentContent(ctx context.Context, requestingAccount
 		// if it's the thumbnail that's requested then the user will have to wait a bit while we process the
 		// large version and derive a thumbnail from it, so use the normal recaching procedure: fetch the media,
 		// process it, then return the thumbnail data
-		data = func(innerCtx context.Context) (io.Reader, int64, error) {
+		data = func(innerCtx context.Context) (io.ReadCloser, int64, error) {
 			transport, err := p.transportController.NewTransportForUsername(innerCtx, requestingUsername)
 			if err != nil {
 				return nil, 0, err
@@ -168,9 +169,9 @@ func (p *processor) getAttachmentContent(ctx context.Context, requestingAccount
 		bufferedReader := bufio.NewReaderSize(pipeReader, int(attachmentContent.ContentLength))
 
 		// the caller will read from the buffered reader, so it doesn't matter if they drop out without reading everything
-		attachmentContent.Content = bufferedReader
+		attachmentContent.Content = io.NopCloser(bufferedReader)
 
-		data = func(innerCtx context.Context) (io.Reader, int64, error) {
+		data = func(innerCtx context.Context) (io.ReadCloser, int64, error) {
 			transport, err := p.transportController.NewTransportForUsername(innerCtx, requestingUsername)
 			if err != nil {
 				return nil, 0, err
@@ -195,17 +196,15 @@ func (p *processor) getAttachmentContent(ctx context.Context, requestingAccount
 		// close the pipewriter after data has been piped into it, so the reader on the other side doesn't block;
 		// we don't need to close the reader here because that's the caller's responsibility
 		postDataCallback = func(innerCtx context.Context) error {
-			// flush the buffered writer into the buffer of the reader...
-			if err := bufferedWriter.Flush(); err != nil {
-				return err
-			}
-
-			// and close the underlying pipe writer
-			if err := pipeWriter.Close(); err != nil {
-				return err
-			}
-
-			return nil
+			// close the underlying pipe writer when we're done with it
+			defer func() {
+				if err := pipeWriter.Close(); err != nil {
+					log.Errorf("getAttachmentContent: error closing pipeWriter: %s", err)
+				}
+			}()
+
+			// and flush the buffered writer into the buffer of the reader
+			return bufferedWriter.Flush()
 		}
 	}
 
diff --git a/internal/processing/media/getfile_test.go b/internal/processing/media/getfile_test.go
index 6e5271607..ba7269535 100644
--- a/internal/processing/media/getfile_test.go
+++ b/internal/processing/media/getfile_test.go
@@ -91,10 +91,7 @@ func (suite *GetFileTestSuite) TestGetRemoteFileUncached() {
 	suite.NotNil(content)
 	b, err := io.ReadAll(content.Content)
 	suite.NoError(err)
-
-	if closer, ok := content.Content.(io.Closer); ok {
-		suite.NoError(closer.Close())
-	}
+	suite.NoError(content.Content.Close())
 
 	suite.Equal(suite.testRemoteAttachments[testAttachment.RemoteURL].Data, b)
 	suite.Equal(suite.testRemoteAttachments[testAttachment.RemoteURL].ContentType, content.ContentType)
@@ -151,9 +148,7 @@ func (suite *GetFileTestSuite) TestGetRemoteFileUncachedInterrupted() {
 	suite.NoError(err)
 
 	// close the reader
-	if closer, ok := content.Content.(io.Closer); ok {
-		suite.NoError(closer.Close())
-	}
+	suite.NoError(content.Content.Close())
 
 	// the attachment should still be updated in the database even though the caller hung up
 	if !testrig.WaitFor(func() bool {
@@ -201,10 +196,7 @@ func (suite *GetFileTestSuite) TestGetRemoteFileThumbnailUncached() {
 	suite.NotNil(content)
 	b, err := io.ReadAll(content.Content)
 	suite.NoError(err)
-
-	if closer, ok := content.Content.(io.Closer); ok {
-		suite.NoError(closer.Close())
-	}
+	suite.NoError(content.Content.Close())
 
 	suite.Equal(thumbnailBytes, b)
 	suite.Equal("image/jpeg", content.ContentType)