[bugfix] Parse video metadata more accurately; allow Range in fileserver (#1342)

* don't serve unused fields for video attachments

* parse video bitrate + duration more accurately

* use ServeContent where appropriate to respect Range

* abstract temp file seeker into its own function

5 files changed, 38 insertions, 36 deletions

diff --git a/internal/api/client/media/mediacreate_test.go b/internal/api/client/media/mediacreate_test.go
index 6ac63a356..320636721 100644
--- a/internal/api/client/media/mediacreate_test.go
+++ b/internal/api/client/media/mediacreate_test.go
@@ -201,7 +201,7 @@ func (suite *MediaCreateTestSuite) TestMediaCreateSuccessful() {
 			Size:   "512x288",
 			Aspect: 1.7777778,
 		},
-		Focus: apimodel.MediaFocus{
+		Focus: &apimodel.MediaFocus{
 			X: -0.5,
 			Y: 0.5,
 		},
@@ -290,7 +290,7 @@ func (suite *MediaCreateTestSuite) TestMediaCreateSuccessfulV2() {
 			Size:   "512x288",
 			Aspect: 1.7777778,
 		},
-		Focus: apimodel.MediaFocus{
+		Focus: &apimodel.MediaFocus{
 			X: -0.5,
 			Y: 0.5,
 		},
diff --git a/internal/api/client/media/mediaupdate_test.go b/internal/api/client/media/mediaupdate_test.go
index 3b1d94368..1425d80ef 100644
--- a/internal/api/client/media/mediaupdate_test.go
+++ b/internal/api/client/media/mediaupdate_test.go
@@ -172,7 +172,7 @@ func (suite *MediaUpdateTestSuite) TestUpdateImage() {
 	suite.EqualValues(apimodel.MediaMeta{
 		Original: apimodel.MediaDimensions{Width: 800, Height: 450, FrameRate: "", Duration: 0, Bitrate: 0, Size: "800x450", Aspect: 1.7777778},
 		Small:    apimodel.MediaDimensions{Width: 256, Height: 144, FrameRate: "", Duration: 0, Bitrate: 0, Size: "256x144", Aspect: 1.7777778},
-		Focus:    apimodel.MediaFocus{X: -0.1, Y: 0.3},
+		Focus:    &apimodel.MediaFocus{X: -0.1, Y: 0.3},
 	}, attachmentReply.Meta)
 	suite.Equal(toUpdate.Blurhash, attachmentReply.Blurhash)
 	suite.Equal(toUpdate.ID, attachmentReply.ID)
diff --git a/internal/api/fileserver/servefile.go b/internal/api/fileserver/servefile.go
index 2b47db6f2..592d83672 100644
--- a/internal/api/fileserver/servefile.go
+++ b/internal/api/fileserver/servefile.go
@@ -29,6 +29,7 @@ import (
 	apimodel "github.com/superseriousbusiness/gotosocial/internal/api/model"
 	apiutil "github.com/superseriousbusiness/gotosocial/internal/api/util"
 	"github.com/superseriousbusiness/gotosocial/internal/gtserror"
+	"github.com/superseriousbusiness/gotosocial/internal/iotools"
 	"github.com/superseriousbusiness/gotosocial/internal/log"
 	"github.com/superseriousbusiness/gotosocial/internal/oauth"
 )
@@ -128,8 +129,34 @@ func (m *Module) ServeFile(c *gin.Context) {
 		return
 	}
 
-	// we're good, return the slurped bytes + the rest of the content
-	c.DataFromReader(http.StatusOK, content.ContentLength, format, io.MultiReader(
-		bytes.NewReader(b), content.Content,
-	), nil)
+	// reconstruct the original content reader
+	r := io.MultiReader(bytes.NewReader(b), content.Content)
+
+	// Check the Range header: if this is a simple query for the whole file, we can return it now.
+	if c.GetHeader("Range") == "" && c.GetHeader("If-Range") == "" {
+		c.DataFromReader(http.StatusOK, content.ContentLength, format, r, nil)
+		return
+	}
+
+	// Range is set, so we need a ReadSeeker to pass to the ServeContent function.
+	tfs, err := iotools.TempFileSeeker(r)
+	if err != nil {
+		err = fmt.Errorf("ServeFile: error creating temp file seeker: %w", err)
+		apiutil.ErrorHandler(c, gtserror.NewErrorInternalError(err), m.processor.InstanceGet)
+		return
+	}
+	defer func() {
+		if err := tfs.Close(); err != nil {
+			log.Errorf("ServeFile: error closing temp file seeker: %s", err)
+		}
+	}()
+
+	// to avoid ServeContent wasting time seeking for the
+	// mime type, set this header already since we know it
+	c.Header("Content-Type", format)
+
+	// allow ServeContent to handle the rest of the request;
+	// it will handle Range as appropriate, and write correct
+	// response headers, http code, etc
+	http.ServeContent(c.Writer, c.Request, fileName, content.ContentUpdated, tfs)
 }
diff --git a/internal/api/model/attachment.go b/internal/api/model/attachment.go
index 244f3cd8d..79de44540 100644
--- a/internal/api/model/attachment.go
+++ b/internal/api/model/attachment.go
@@ -98,40 +98,12 @@ type Attachment struct {
 //
 // swagger:model mediaMeta
 type MediaMeta struct {
-	Length string `json:"length,omitempty"`
-	// Duration of the media in seconds.
-	// Only set for video and audio.
-	// example: 5.43
-	Duration float32 `json:"duration,omitempty"`
-	// Framerate of the media.
-	// Only set for video and gifs.
-	// example: 30
-	FPS uint16 `json:"fps,omitempty"`
-	// Size of the media, in the format `[width]x[height]`.
-	// Not set for audio.
-	// example: 1920x1080
-	Size string `json:"size,omitempty"`
-	// Width of the media in pixels.
-	// Not set for audio.
-	// example: 1920
-	Width int `json:"width,omitempty"`
-	// Height of the media in pixels.
-	// Not set for audio.
-	// example: 1080
-	Height int `json:"height,omitempty"`
-	// Aspect ratio of the media.
-	// Equal to width / height.
-	// example: 1.777777778
-	Aspect        float32 `json:"aspect,omitempty"`
-	AudioEncode   string  `json:"audio_encode,omitempty"`
-	AudioBitrate  string  `json:"audio_bitrate,omitempty"`
-	AudioChannels string  `json:"audio_channels,omitempty"`
 	// Dimensions of the original media.
 	Original MediaDimensions `json:"original"`
 	// Dimensions of the thumbnail/small version of the media.
 	Small MediaDimensions `json:"small,omitempty"`
 	// Focus data for the media.
-	Focus MediaFocus `json:"focus,omitempty"`
+	Focus *MediaFocus `json:"focus,omitempty"`
 }
 
 // MediaFocus models the focal point of a piece of media.
diff --git a/internal/api/model/content.go b/internal/api/model/content.go
index 94b32d112..4c0151c2c 100644
--- a/internal/api/model/content.go
+++ b/internal/api/model/content.go
@@ -21,6 +21,7 @@ package model
 import (
 	"io"
 	"net/url"
+	"time"
 )
 
 // Content wraps everything needed to serve a blob of content (some kind of media) through the API.
@@ -29,6 +30,8 @@ type Content struct {
 	ContentType string
 	// ContentLength in bytes
 	ContentLength int64
+	// Time when the content was last updated.
+	ContentUpdated time.Time
 	// Actual content
 	Content io.ReadCloser
 	// Resource URL to forward to if the file can be fetched from the storage directly (e.g signed S3 URL)