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chiyi
2026-07-03 00:15:41 +08:00
parent 7bb0531c4b
commit 273892f98f
15 changed files with 416 additions and 61 deletions
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backend/go.mod
+8 -7
View File
@@ -12,7 +12,7 @@ require (
github.com/google/uuid v1.6.0
github.com/matoous/go-nanoid/v2 v2.1.0
github.com/redis/go-redis/v9 v9.16.0
golang.org/x/crypto v0.46.0
golang.org/x/crypto v0.51.0
gorm.io/datatypes v1.2.7
gorm.io/driver/postgres v1.6.0
gorm.io/gorm v1.31.0
@@ -60,12 +60,13 @@ require (
github.com/ugorji/go/codec v1.3.0 // indirect
go.uber.org/mock v0.5.2 // indirect
golang.org/x/arch v0.20.0 // indirect
golang.org/x/mod v0.30.0 // indirect
golang.org/x/net v0.48.0 // indirect
golang.org/x/sync v0.19.0 // indirect
golang.org/x/sys v0.39.0 // indirect
golang.org/x/text v0.32.0 // indirect
golang.org/x/tools v0.39.0 // indirect
golang.org/x/image v0.43.0 // indirect
golang.org/x/mod v0.36.0 // indirect
golang.org/x/net v0.54.0 // indirect
golang.org/x/sync v0.21.0 // indirect
golang.org/x/sys v0.44.0 // indirect
golang.org/x/text v0.38.0 // indirect
golang.org/x/tools v0.45.0 // indirect
google.golang.org/protobuf v1.36.9 // indirect
gorm.io/driver/mysql v1.5.6 // indirect
)
backend/go.sum
+16
View File
@@ -138,25 +138,41 @@ golang.org/x/arch v0.20.0 h1:dx1zTU0MAE98U+TQ8BLl7XsJbgze2WnNKF/8tGp/Q6c=
golang.org/x/arch v0.20.0/go.mod h1:bdwinDaKcfZUGpH09BB7ZmOfhalA8lQdzl62l8gGWsk=
golang.org/x/crypto v0.46.0 h1:cKRW/pmt1pKAfetfu+RCEvjvZkA9RimPbh7bhFjGVBU=
golang.org/x/crypto v0.46.0/go.mod h1:Evb/oLKmMraqjZ2iQTwDwvCtJkczlDuTmdJXoZVzqU0=
golang.org/x/crypto v0.51.0 h1:IBPXwPfKxY7cWQZ38ZCIRPI50YLeevDLlLnyC5wRGTI=
golang.org/x/crypto v0.51.0/go.mod h1:8AdwkbraGNABw2kOX6YFPs3WM22XqI4EXEd8g+x7Oc8=
golang.org/x/image v0.43.0 h1:FLxcP4ec2350nTfOC8ysKtqYSIFbk/QGjw1ZHNP4tsY=
golang.org/x/image v0.43.0/go.mod h1:rrpelvGFt+kLPAjPM4HeWPgrl0FtafueU//e5N0qk/Q=
golang.org/x/mod v0.30.0 h1:fDEXFVZ/fmCKProc/yAXXUijritrDzahmwwefnjoPFk=
golang.org/x/mod v0.30.0/go.mod h1:lAsf5O2EvJeSFMiBxXDki7sCgAxEUcZHXoXMKT4GJKc=
golang.org/x/mod v0.36.0 h1:JJjpVx6myfUsUdAzZuOSTTmRE0PfZeNWzzvKrP7amb4=
golang.org/x/mod v0.36.0/go.mod h1:moc6ELqsWcOw5Ef3xVprK5ul/MvtVvkIXLziUOICjUQ=
golang.org/x/net v0.0.0-20211104170005-ce137452f963/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
golang.org/x/net v0.48.0 h1:zyQRTTrjc33Lhh0fBgT/H3oZq9WuvRR5gPC70xpDiQU=
golang.org/x/net v0.48.0/go.mod h1:+ndRgGjkh8FGtu1w1FGbEC31if4VrNVMuKTgcAAnQRY=
golang.org/x/net v0.54.0 h1:2zJIZAxAHV/OHCDTCOHAYehQzLfSXuf/5SoL/Dv6w/w=
golang.org/x/net v0.54.0/go.mod h1:Sj4oj8jK6XmHpBZU/zWHw3BV3abl4Kvi+Ut7cQcY+cQ=
golang.org/x/sync v0.19.0 h1:vV+1eWNmZ5geRlYjzm2adRgW2/mcpevXNg50YZtPCE4=
golang.org/x/sync v0.19.0/go.mod h1:9KTHXmSnoGruLpwFjVSX0lNNA75CykiMECbovNTZqGI=
golang.org/x/sync v0.21.0 h1:HLII4xRRTtCRkxYp4HNFF0Js/Og6q2i++KXbg0gHCwM=
golang.org/x/sync v0.21.0/go.mod h1:9xrNwdLfx4jkKbNva9FpL6vEN7evnE43NNNJQ2LF3+0=
golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
golang.org/x/sys v0.0.0-20210423082822-04245dca01da/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
golang.org/x/sys v0.39.0 h1:CvCKL8MeisomCi6qNZ+wbb0DN9E5AATixKsvNtMoMFk=
golang.org/x/sys v0.39.0/go.mod h1:OgkHotnGiDImocRcuBABYBEXf8A9a87e/uXjp9XT3ks=
golang.org/x/sys v0.44.0 h1:ildZl3J4uzeKP07r2F++Op7E9B29JRUy+a27EibtBTQ=
golang.org/x/sys v0.44.0/go.mod h1:4GL1E5IUh+htKOUEOaiffhrAeqysfVGipDYzABqnCmw=
golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
golang.org/x/text v0.3.6/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
golang.org/x/text v0.32.0 h1:ZD01bjUt1FQ9WJ0ClOL5vxgxOI/sVCNgX1YtKwcY0mU=
golang.org/x/text v0.32.0/go.mod h1:o/rUWzghvpD5TXrTIBuJU77MTaN0ljMWE47kxGJQ7jY=
golang.org/x/text v0.38.0 h1:sXmwo9DwP3OK9EZ7PqAdaooSGozfl/3a6/xJcbzPRhE=
golang.org/x/text v0.38.0/go.mod h1:YXZt3QhHUKYT53r2lLKFIVi6Ao1jdzrTR/KQ09qyxF4=
golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
golang.org/x/tools v0.39.0 h1:ik4ho21kwuQln40uelmciQPp9SipgNDdrafrYA4TmQQ=
golang.org/x/tools v0.39.0/go.mod h1:JnefbkDPyD8UU2kI5fuf8ZX4/yUeh9W877ZeBONxUqQ=
golang.org/x/tools v0.45.0 h1:18qN3FAooORvApf5XjCXgsuayZOEtXf6JK18I3+ONa8=
golang.org/x/tools v0.45.0/go.mod h1:LuUGqqaXcXMEFEruIVJVm5mgDD8vww/z/SR1gQ4uE/0=
google.golang.org/protobuf v1.36.9 h1:w2gp2mA27hUeUzj9Ex9FBjsBm40zfaDtEWow293U7Iw=
google.golang.org/protobuf v1.36.9/go.mod h1:fuxRtAxBytpl4zzqUh6/eyUujkJdNiuEkXntxiD/uRU=
gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
backend/internal/http/handler/images.go
+18 -1
View File
@@ -38,7 +38,16 @@ func (h *ImageHandler) Serve(c *gin.Context) {
return
}
public, err := h.imageAccess.IsPublic(c.Request.Context(), rel)
// A thumbnail shares its original's visibility, and old images without a
// stored thumb fall back to the original object.
origRel := rel
if service.IsThumbKey(rel) {
origRel = service.OrigKey(rel)
} else if service.IsLastFrameKey(rel) {
origRel = service.LastFrameOrigKey(rel)
}
public, err := h.imageAccess.IsPublic(c.Request.Context(), origRel)
if err != nil {
c.JSON(http.StatusInternalServerError, gin.H{"detail": "failed to authorize image"})
return
@@ -65,6 +74,14 @@ func (h *ImageHandler) Serve(c *gin.Context) {
c.JSON(http.StatusBadGateway, gin.H{"detail": "failed to fetch object"})
return
}
if resp.StatusCode == http.StatusNotFound && origRel != rel {
resp.Body.Close()
resp, err = h.store.Get(c.Request.Context(), origRel, c.GetHeader("Range"))
if err != nil {
c.JSON(http.StatusBadGateway, gin.H{"detail": "failed to fetch object"})
return
}
}
defer resp.Body.Close()
if resp.StatusCode == http.StatusNotFound {
c.JSON(http.StatusNotFound, gin.H{"detail": "not found"})
backend/internal/provider/grok/client.go
+94 -14
View File
@@ -153,6 +153,14 @@ func (c *Client) FetchCreditsBalance(ctx context.Context, token string) (map[str
used = fullCredits
}
remaining := fullCredits - used
// 恢复时间: prefer the subscription's billing-period end (when the plan renews
// and credits reset) over the credits-config timestamp. Free accounts have no
// subscription, so this falls back to the credits-config reset above.
sub, _ := c.FetchSubscription(ctx, token)
if sub != nil && strings.TrimSpace(sub.BillingPeriodEnd) != "" {
reset = strings.TrimSpace(sub.BillingPeriodEnd)
}
return map[string]any{
"remaining": remaining,
"used": used,
@@ -163,6 +171,78 @@ func (c *Client) FetchCreditsBalance(ctx context.Context, token string) (map[str
}, nil
}
// Subscription is the membership view parsed from GET /rest/subscriptions.
type Subscription struct {
Member bool // an active subscription exists
Tier string // e.g. SUBSCRIPTION_TIER_GROK_PRO ("" for free)
Status string // e.g. SUBSCRIPTION_STATUS_ACTIVE
BillingPeriodEnd string // RFC3339; when the plan renews / credits reset
FreeTrial bool // currently in a free-trial offer
}
// FetchSubscription reads GET /rest/subscriptions and reports the account's
// membership. An empty subscriptions array means a free account (Member=false).
// A 401/403 maps to ErrAuth; other transport/HTTP errors are returned so callers
// can treat them as best-effort (they already have the credit balance).
func (c *Client) FetchSubscription(ctx context.Context, token string) (*Subscription, error) {
token = strings.TrimSpace(strings.TrimPrefix(token, "Bearer "))
if token == "" {
return nil, ErrAuth
}
client, err := c.newTLSClient()
if err != nil {
return nil, err
}
req, err := http.NewRequest(http.MethodGet, apiBase+"/rest/subscriptions", nil)
if err != nil {
return nil, err
}
req = req.WithContext(ctx)
c.applyHeaders(req, token, nil)
resp, err := client.Do(req)
if err != nil {
return nil, fmt.Errorf("%w: %v", ErrTemporaryUpstream, err)
}
defer resp.Body.Close()
raw, _ := io.ReadAll(resp.Body)
if resp.StatusCode == 401 || resp.StatusCode == 403 {
return nil, ErrAuth
}
if resp.StatusCode != 200 {
return nil, fmt.Errorf("%w: subscriptions http %d", ErrTemporaryUpstream, resp.StatusCode)
}
var body struct {
Subscriptions []struct {
Tier string `json:"tier"`
Status string `json:"status"`
BillingPeriodEnd string `json:"billingPeriodEnd"`
ActiveOffer struct {
FreeTrial *struct {
TrialDays int `json:"trialDays"`
} `json:"freeTrial"`
} `json:"activeOffer"`
} `json:"subscriptions"`
}
if err := json.Unmarshal(raw, &body); err != nil {
return nil, fmt.Errorf("%w: subscriptions non-json", ErrTemporaryUpstream)
}
out := &Subscription{}
// Pick the active subscription (fall back to the first entry) as the membership.
for i, s := range body.Subscriptions {
if i == 0 || strings.EqualFold(s.Status, "SUBSCRIPTION_STATUS_ACTIVE") {
out.Member = true
out.Tier = strings.TrimSpace(s.Tier)
out.Status = strings.TrimSpace(s.Status)
out.BillingPeriodEnd = strings.TrimSpace(s.BillingPeriodEnd)
out.FreeTrial = s.ActiveOffer.FreeTrial != nil
if strings.EqualFold(s.Status, "SUBSCRIPTION_STATUS_ACTIVE") {
break
}
}
}
return out, nil
}
// FetchSession reads the account profile via GET /api/auth/session and returns
// (email, userID). A 401/403 means the sso session is dead → ErrAuth.
func (c *Client) FetchSession(ctx context.Context, token string) (email, userID string, err error) {
@@ -271,21 +351,21 @@ func statsigID(path, method string) string {
// extra overrides/adds per-request headers (e.g. content-type).
func (c *Client) applyHeaders(req *http.Request, token string, extra map[string]string) {
h := http.Header{
"accept": {"*/*"},
"accept-language": {"en-US,en;q=0.9"},
"content-type": {"application/json"},
"origin": {origin},
"referer": {origin + "/"},
"user-agent": {userAgent},
"x-statsig-id": {statsigID(req.URL.Path, req.Method)},
"x-xai-request-id": {uuid.NewString()},
"sec-ch-ua": {`"Chromium";v="133", "Not(A:Brand";v="99"`},
"sec-ch-ua-mobile": {"?0"},
"accept": {"*/*"},
"accept-language": {"en-US,en;q=0.9"},
"content-type": {"application/json"},
"origin": {origin},
"referer": {origin + "/"},
"user-agent": {userAgent},
"x-statsig-id": {statsigID(req.URL.Path, req.Method)},
"x-xai-request-id": {uuid.NewString()},
"sec-ch-ua": {`"Chromium";v="133", "Not(A:Brand";v="99"`},
"sec-ch-ua-mobile": {"?0"},
"sec-ch-ua-platform": {`"Windows"`},
"sec-fetch-dest": {"empty"},
"sec-fetch-mode": {"cors"},
"sec-fetch-site": {"same-origin"},
"cookie": {"sso=" + token + "; sso-rw=" + token},
"sec-fetch-dest": {"empty"},
"sec-fetch-mode": {"cors"},
"sec-fetch-site": {"same-origin"},
"cookie": {"sso=" + token + "; sso-rw=" + token},
}
for k, v := range extra {
h[k] = []string{v}
backend/internal/provider/grok/video.go
+16 -3
View File
@@ -331,9 +331,10 @@ func mapStatus(path string, status int, raw []byte) error {
switch {
case status == 200:
return nil
case status == 403 && strings.Contains(strings.ToLower(string(raw)), "anti-bot"):
// grok bot-detection (proxy/TLS fingerprint), NOT a dead token — transient,
// so a good account isn't killed by an IP/anti-bot hiccup.
case status == 403 && isBotChallenge(string(raw)):
// grok bot-detection or a Cloudflare challenge page ("Just a moment…"),
// NOT a dead token — transient, so a good account isn't killed by an
// IP/anti-bot hiccup.
return fmt.Errorf("%w: %s 403 %s", ErrTemporaryUpstream, path, clip(raw, 160))
case status == 401 || status == 403:
return fmt.Errorf("%w: %s %d %s", ErrAuth, path, status, clip(raw, 160))
@@ -355,6 +356,18 @@ func mapStatus(path string, status int, raw []byte) error {
}
}
// isBotChallenge reports whether a 403 body is an anti-bot interstitial rather
// than a real auth rejection: grok's own "anti-bot" marker or a Cloudflare
// challenge page ("Just a moment…" / cf-chl / challenge-platform).
func isBotChallenge(s string) bool {
s = strings.ToLower(s)
return strings.Contains(s, "anti-bot") ||
strings.Contains(s, "just a moment") ||
strings.Contains(s, "cf-chl") ||
strings.Contains(s, "challenge-platform") ||
strings.Contains(s, "cf_chl")
}
func isCreditError(s string) bool {
s = strings.ToLower(s)
return strings.Contains(s, "usagepoolexhausted") || strings.Contains(s, "credit") || strings.Contains(s, "insufficient") || strings.Contains(s, "quota")
backend/internal/service/admin_read.go
+20 -17
View File
@@ -62,25 +62,25 @@ func (s *AdminReadService) ModelsView(ctx context.Context) ([]map[string]any, er
out := make([]map[string]any, 0, len(items))
for _, item := range items {
out = append(out, map[string]any{
"id": item.ID,
"type": item.Type,
"name": item.Name,
"provider": item.Provider,
"enabled": item.Enabled,
"ratios": repo.JSONStrings(item.Ratios),
"prices": map[string]any(item.Prices),
"resolutions": repo.JSONStrings(item.Resolutions),
"image_to_image": item.ImageToImage,
"duration_prices": map[string]any(item.DurationPrices),
"id": item.ID,
"type": item.Type,
"name": item.Name,
"provider": item.Provider,
"enabled": item.Enabled,
"ratios": repo.JSONStrings(item.Ratios),
"prices": map[string]any(item.Prices),
"resolutions": repo.JSONStrings(item.Resolutions),
"image_to_image": item.ImageToImage,
"duration_prices": map[string]any(item.DurationPrices),
"prices_agent": map[string]any(item.PricesAgent),
"duration_prices_agent": map[string]any(item.DurationPricesAgent),
"durations": repo.JSONStrings(item.Durations),
"max_reference_images": item.MaxReferenceImages,
"reference_mode": item.ReferenceMode,
"weight": item.Weight,
"generation_count": item.GenerationCount,
"created_at": item.CreatedAt,
"updated_at": item.UpdatedAt,
"durations": repo.JSONStrings(item.Durations),
"max_reference_images": item.MaxReferenceImages,
"reference_mode": item.ReferenceMode,
"weight": item.Weight,
"generation_count": item.GenerationCount,
"created_at": item.CreatedAt,
"updated_at": item.UpdatedAt,
})
}
return out, nil
@@ -574,6 +574,9 @@ func (s *AdminReadService) scanGeneratedFiles(ctx context.Context) ([]generatedF
if isReferenceFile(o.Key) {
continue // reference uploads are not generated outputs — hide from gallery
}
if IsThumbKey(o.Key) || IsLastFrameKey(o.Key) {
continue // thumbnails / last-frame stills are derived — only originals are listed
}
kind := mediaKind(o.Key)
if kind == "" {
continue
backend/internal/service/thumbnail.go
+71
View File
@@ -0,0 +1,71 @@
package service
import (
"bytes"
"image"
"image/jpeg"
"strings"
"golang.org/x/image/draw"
_ "image/gif"
_ "image/jpeg"
_ "image/png"
_ "golang.org/x/image/webp"
)
// thumbSuffix is appended to an image's object key to form its thumbnail key
// ("u/x.png" → "u/x.png.thumb.jpg"). List views load the thumbnail; preview and
// download always use the original.
const thumbSuffix = ".thumb.jpg"
// thumbMaxDim bounds the thumbnail's longest side. 512px is crisp for grid
// cards / table rows while staying ~20-50 KB as JPEG.
const thumbMaxDim = 512
// ThumbKey returns the thumbnail object key for an image key.
func ThumbKey(rel string) string { return rel + thumbSuffix }
// IsThumbKey reports whether name refers to a thumbnail object, and OrigKey
// maps a thumbnail key back to its original image key.
func IsThumbKey(name string) bool { return strings.HasSuffix(name, thumbSuffix) }
func OrigKey(name string) string { return strings.TrimSuffix(name, thumbSuffix) }
// makeThumbnail downscales an image to thumbMaxDim (longest side) and encodes
// it as JPEG. Images already small enough are re-encoded as-is (so the thumb
// object always exists once generated). Returns an error for undecodable input
// (e.g. video bytes) — callers treat thumbnailing as best-effort.
func makeThumbnail(b []byte) ([]byte, error) {
src, _, err := image.Decode(bytes.NewReader(b))
if err != nil {
return nil, err
}
bounds := src.Bounds()
w, h := bounds.Dx(), bounds.Dy()
tw, th := w, h
if w > thumbMaxDim || h > thumbMaxDim {
if w >= h {
tw = thumbMaxDim
th = h * thumbMaxDim / w
} else {
th = thumbMaxDim
tw = w * thumbMaxDim / h
}
if tw < 1 {
tw = 1
}
if th < 1 {
th = 1
}
}
// JPEG has no alpha — composite onto white so transparent PNGs don't go black.
dst := image.NewRGBA(image.Rect(0, 0, tw, th))
draw.Draw(dst, dst.Bounds(), image.White, image.Point{}, draw.Src)
draw.CatmullRom.Scale(dst, dst.Bounds(), src, bounds, draw.Over, nil)
var out bytes.Buffer
if err := jpeg.Encode(&out, dst, &jpeg.Options{Quality: 78}); err != nil {
return nil, err
}
return out.Bytes(), nil
}
backend/internal/service/v1.go
+16
View File
@@ -515,6 +515,11 @@ func (s *V1Service) prepareImageExecution(ctx context.Context, principal *APIPri
_ = s.events.UpdateStatus(ctx, eventID, "failed", "storage upload failed: "+err.Error(), 0)
return nil, fmt.Errorf("%w: %v", ErrProviderExecution, err)
}
// Best-effort thumbnail for list views; the image serving route falls
// back to the original when the thumb object is missing.
if thumb, terr := makeThumbnail(imageBytes); terr == nil {
_ = s.store.Put(genCtx, ThumbKey(relativePath), thumb, "image/jpeg")
}
}
elapsedMS := int(time.Since(startedAt).Milliseconds())
if err := s.events.UpdateStatus(ctx, eventID, "success", "", elapsedMS); err != nil {
@@ -648,6 +653,17 @@ func (s *V1Service) prepareVideoExecution(ctx context.Context, principal *APIPri
_ = s.events.UpdateStatus(ctx, eventID, "failed", "storage upload failed: "+err.Error(), 0)
return nil, fmt.Errorf("%w: %v", ErrProviderExecution, err)
}
// Best-effort stills: first frame (downscaled) for list thumbnails and
// the full-res last frame for 首尾帧 continuation. Missing objects fall
// back to the video itself at serve time.
if thumb, last, terr := extractVideoFrames(genCtx, videoBytes); terr == nil {
if len(thumb) > 0 {
_ = s.store.Put(genCtx, ThumbKey(relativePath), thumb, "image/jpeg")
}
if len(last) > 0 {
_ = s.store.Put(genCtx, LastFrameKey(relativePath), last, "image/jpeg")
}
}
}
elapsedMS := int(time.Since(startedAt).Milliseconds())
if err := s.events.UpdateStatus(ctx, eventID, "success", "", elapsedMS); err != nil {
backend/internal/service/video_frames.go
+76
View File
@@ -0,0 +1,76 @@
package service
import (
"context"
"errors"
"fmt"
"os"
"os/exec"
"path/filepath"
"strings"
)
// lastFrameSuffix marks a video's FULL-RESOLUTION last-frame still
// ("u/x.mp4" → "u/x.mp4.last.jpg"). The 画图台 uses it as the 首帧 reference
// when continuing a video (首尾帧 models); the first-frame THUMBNAIL reuses
// thumbSuffix so list views load videos and images the same way.
const lastFrameSuffix = ".last.jpg"
// LastFrameKey returns the last-frame object key for a video key, and
// IsLastFrameKey reports whether name refers to such a derived object.
func LastFrameKey(rel string) string { return rel + lastFrameSuffix }
func IsLastFrameKey(name string) bool { return strings.HasSuffix(name, lastFrameSuffix) }
func LastFrameOrigKey(name string) string { return strings.TrimSuffix(name, lastFrameSuffix) }
// extractVideoFrames pulls two stills from an mp4 via ffmpeg: the FIRST frame
// downscaled for list thumbnails (≤thumbMaxDim) and the LAST frame at full
// resolution. Callers treat this as best-effort — any missing ffmpeg or decode
// failure just means the derived objects aren't stored.
func extractVideoFrames(ctx context.Context, video []byte) (thumb, last []byte, err error) {
ffmpeg, err := exec.LookPath("ffmpeg")
if err != nil {
return nil, nil, errors.New("ffmpeg not installed")
}
dir, err := os.MkdirTemp("", "vidframes-*")
if err != nil {
return nil, nil, err
}
defer os.RemoveAll(dir)
in := filepath.Join(dir, "in.mp4")
if err := os.WriteFile(in, video, 0o600); err != nil {
return nil, nil, err
}
thumbPath := filepath.Join(dir, "thumb.jpg")
if out, err := exec.CommandContext(ctx, ffmpeg, "-y", "-i", in,
"-vf", fmt.Sprintf("scale='min(%d,iw)':-2", thumbMaxDim),
"-frames:v", "1", "-q:v", "4", thumbPath).CombinedOutput(); err != nil {
return nil, nil, fmt.Errorf("ffmpeg first frame: %v: %s", err, clipTail(out))
}
thumb, err = os.ReadFile(thumbPath)
if err != nil {
return nil, nil, err
}
// -sseof seeks from the end; a tiny negative offset lands on the final
// frame(s). Some encodes have sparse keyframes near EOF, so fall back to a
// wider window before giving up (thumb alone is still useful).
lastPath := filepath.Join(dir, "last.jpg")
for _, off := range []string{"-0.1", "-1"} {
_ = exec.CommandContext(ctx, ffmpeg, "-y", "-sseof", off, "-i", in,
"-frames:v", "1", "-q:v", "2", "-update", "1", lastPath).Run()
if b, rerr := os.ReadFile(lastPath); rerr == nil && len(b) > 0 {
last = b
break
}
}
return thumb, last, nil
}
func clipTail(b []byte) string {
s := strings.TrimSpace(string(b))
if len(s) > 300 {
s = s[len(s)-300:]
}
return s
}