feat: generate multi-image thumbnails for multi-image tweets (#373)

CHANGELOG.md

@@ -5,6 +5,7 @@
 - Breaking: Go version 1.17 is now the minimum required version to build this. (#292)
 - Breaking: Thumbnail generation now requires libvips. See [docs/build.md](./docs/build.md) for prerequisite instructions. (#366, #369)
 - Breaking: Resolver caches are now stored in PostgreSQL. See [docs/build.md](./docs/build.md) for prerequisite instructions. (#271)
+- Twitter: Generate thumbnails with all images of a tweet. (#373)
 - YouTube: Added support for 'YouTube shorts' URLs. (#299)
 - Fix: SevenTV emotes now resolve correctly. (#281, #288, #307)
 - Fix: YouTube videos are no longer resolved as channels. (#284)

internal/caches/twitchusernamecache/cache.go

@@ -19,5 +19,7 @@ func New(ctx context.Context, cfg config.APIConfig, pool db.Pool, helixClient *h
 		helixClient: helixClient,
 	}
 
-	return cache.NewPostgreSQLCache(ctx, cfg, pool, "twitch:username", usernameLoader, 1*time.Hour)
+	return cache.NewPostgreSQLCache(
+		ctx, cfg, pool, cache.NewPrefixKeyProvider("twitch:username"), usernameLoader, 1*time.Hour,
+	)
 }

internal/db/pool.go

@@ -12,6 +12,7 @@ import (
 )
 
 type Pool interface {
+	Query(ctx context.Context, sql string, args ...interface{}) (pgx.Rows, error)
 	QueryRow(ctx context.Context, sql string, args ...interface{}) pgx.Row
 	Exec(ctx context.Context, sql string, arguments ...interface{}) (pgconn.CommandTag, error)
 	Ping(ctx context.Context) error
@@ -21,7 +22,6 @@ type Pool interface {
 
 func NewPool(ctx context.Context, dsn string) (Pool, error) {
 	pool, err := pgxpool.Connect(ctx, dsn)
-
 	if err != nil {
 		return nil, fmt.Errorf("error connecting to pool: %w", err)
 	}

internal/migration/3_dependent_cache.go

@@ -0,0 +1,45 @@
+//go:build !test || migrationtest
+
+package migration
+
+import (
+	"context"
+
+	"github.com/jackc/pgx/v4"
+)
+
+func init() {
+	// The version of this migration
+	const migrationVersion = 3
+
+	Register(
+		migrationVersion,
+		func(ctx context.Context, tx pgx.Tx) error {
+			// The Up action of this migration
+			_, err := tx.Exec(ctx, `
+CREATE TABLE dependent_values (
+    key TEXT UNIQUE NOT NULL,
+    parent_key TEXT NOT NULL,
+    value bytea NOT NULL,
+    http_content_type TEXT NOT NULL,
+    committed BOOLEAN NOT NULL DEFAULT FALSE,
+    expiration_timestamp TIMESTAMP NOT NULL
+);
+
+CREATE INDEX idx_dependent_values_key ON dependent_values(key);
+CREATE INDEX idx_dependent_values_parent_entry_key ON dependent_values(parent_key);
+CREATE INDEX idx_dependent_values_committed ON dependent_values(committed);
+		`)
+
+			return err
+		},
+		func(ctx context.Context, tx pgx.Tx) error {
+			// The Down action of this migration
+			_, err := tx.Exec(ctx, `
+DROP TABLE dependent_values;
+		`)
+
+			return err
+		},
+	)
+}

internal/resolvers/betterttv/emote_resolver.go

@@ -49,7 +49,9 @@ func NewEmoteResolver(ctx context.Context, cfg config.APIConfig, pool db.Pool, e
 	emoteLoader := NewEmoteLoader(emoteAPIURL)
 
 	r := &EmoteResolver{
-		emoteCache: cache.NewPostgreSQLCache(ctx, cfg, pool, "betterttv:emote", resolver.NewResponseMarshaller(emoteLoader), 1*time.Hour),
+		emoteCache: cache.NewPostgreSQLCache(
+			ctx, cfg, pool, cache.NewPrefixKeyProvider("betterttv:emote"),
+			resolver.NewResponseMarshaller(emoteLoader), 1*time.Hour),
 	}
 
 	return r

internal/resolvers/default/initialize.go

@@ -23,16 +23,16 @@ const (
 <b>URL:</b> {{.URL}}</div>`
 )
 
-var (
-	defaultTooltip = template.Must(template.New("default_tooltip").Parse(defaultTooltipString))
-)
+var defaultTooltip = template.Must(template.New("default_tooltip").Parse(defaultTooltipString))
 
 func Initialize(ctx context.Context, cfg config.APIConfig, pool db.Pool, router *chi.Mux, helixClient *helix.Client) {
 	defaultLinkResolver := New(ctx, cfg, pool, helixClient)
 
 	cached := stampede.Handler(512, 10*time.Second)
 	imageCached := stampede.Handler(256, 2*time.Second)
+	generatedValuesCached := stampede.Handler(256, 2*time.Second)
 
 	router.With(cached).Get("/link_resolver/{url}", defaultLinkResolver.HandleRequest)
 	router.With(imageCached).Get("/thumbnail/{url}", defaultLinkResolver.HandleThumbnailRequest)
+	router.With(generatedValuesCached).Get("/generated/{url}", defaultLinkResolver.HandleGeneratedValueRequest)
 }

internal/resolvers/default/link_resolver.go

@@ -33,6 +33,7 @@ type LinkResolver struct {
 
 	linkCache      cache.Cache
 	thumbnailCache cache.Cache
+	generatedCache cache.DependentCache
 }
 
 func (r *LinkResolver) HandleRequest(w http.ResponseWriter, req *http.Request) {
@@ -148,7 +149,6 @@ func (r *LinkResolver) HandleThumbnailRequest(w http.ResponseWriter, req *http.R
 	}
 
 	response, err := r.thumbnailCache.Get(ctx, url, req)
-
 	if err != nil {
 		log.Errorw("Error in thumbnail request",
 			"url", url,
@@ -167,7 +167,50 @@ func (r *LinkResolver) HandleThumbnailRequest(w http.ResponseWriter, req *http.R
 	}
 }
 
+func (r *LinkResolver) HandleGeneratedValueRequest(w http.ResponseWriter, req *http.Request) {
+	ctx := req.Context()
+	log := logger.FromContext(ctx)
+
+	url, err := utils.UnescapeURLArgument(req, "url")
+	if err != nil {
+		_, err = resolver.WriteInvalidURL(w)
+		if err != nil {
+			log.Errorw("Error writing response",
+				"error", err,
+			)
+		}
+		return
+	}
+
+	payload, contentType, err := r.generatedCache.Get(ctx, url)
+	if err != nil {
+		log.Errorw("Error in request for generated value",
+			"url", url,
+			"error", err,
+		)
+		return
+	}
+
+	if payload == nil {
+		log.Warnw("Requested generated value does not exist",
+			"url", url,
+		)
+		return
+	}
+
+	w.Header().Add("Content-Type", contentType)
+	w.WriteHeader(http.StatusOK)
+	_, err = w.Write(payload)
+	if err != nil {
+		log.Errorw("Error writing response",
+			"error", err,
+		)
+	}
+}
+
 func New(ctx context.Context, cfg config.APIConfig, pool db.Pool, helixClient *helix.Client) *LinkResolver {
+	generatedCache := cache.NewPostgreSQLDependentCache(ctx, cfg, pool, cache.NewPrefixKeyProvider("default:dependent"))
+
 	customResolvers := []resolver.Resolver{}
 
 	// Register Link Resolvers from internal/resolvers/
@@ -179,7 +222,7 @@ func New(ctx context.Context, cfg config.APIConfig, pool db.Pool, helixClient *h
 	oembed.Initialize(ctx, cfg, pool, &customResolvers)
 	supinic.Initialize(ctx, cfg, pool, &customResolvers)
 	twitch.Initialize(ctx, cfg, pool, helixClient, &customResolvers)
-	twitter.Initialize(ctx, cfg, pool, &customResolvers)
+	twitter.Initialize(ctx, cfg, pool, &customResolvers, generatedCache)
 	wikipedia.Initialize(ctx, cfg, pool, &customResolvers)
 	youtube.Initialize(ctx, cfg, pool, &customResolvers)
 	seventv.Initialize(ctx, cfg, pool, &customResolvers)
@@ -195,11 +238,20 @@ func New(ctx context.Context, cfg config.APIConfig, pool db.Pool, helixClient *h
 		enableLilliput:   cfg.EnableLilliput,
 	}
 
+	thumbnailCache := cache.NewPostgreSQLCache(
+		ctx, cfg, pool, cache.NewPrefixKeyProvider("default:thumbnail"), thumbnailLoader,
+		10*time.Minute,
+	)
+	linkCache := cache.NewPostgreSQLCache(
+		ctx, cfg, pool, cache.NewPrefixKeyProvider("default:link"), linkLoader, 10*time.Minute,
+	)
+
 	r := &LinkResolver{
 		customResolvers: customResolvers,
 
-		linkCache:      cache.NewPostgreSQLCache(ctx, cfg, pool, "default:link", linkLoader, 10*time.Minute),
-		thumbnailCache: cache.NewPostgreSQLCache(ctx, cfg, pool, "default:thumbnail", thumbnailLoader, 10*time.Minute),
+		linkCache:      linkCache,
+		thumbnailCache: thumbnailCache,
+		generatedCache: generatedCache,
 	}
 
 	return r

internal/resolvers/discord/invite_resolver.go

@@ -45,7 +45,9 @@ func NewInviteResolver(ctx context.Context, cfg config.APIConfig, pool db.Pool)
 	// We cache invites longer on purpose as the API is pretty strict with its rate limiting, and the information changes very seldomly anyway
 	// TODO: Log 429 errors from the loader
 	r := &InviteResolver{
-		inviteCache: cache.NewPostgreSQLCache(ctx, cfg, pool, "discord:invite", resolver.NewResponseMarshaller(inviteLoader), 6*time.Hour),
+		inviteCache: cache.NewPostgreSQLCache(
+			ctx, cfg, pool, cache.NewPrefixKeyProvider("discord:invite"),
+			resolver.NewResponseMarshaller(inviteLoader), 6*time.Hour),
 	}
 
 	return r

internal/resolvers/frankerfacez/emote_resolver.go

@@ -47,7 +47,9 @@ func NewEmoteResolver(ctx context.Context, cfg config.APIConfig, pool db.Pool, e
 	emoteLoader := NewEmoteLoader(emoteAPIURL)
 
 	r := &EmoteResolver{
-		emoteCache: cache.NewPostgreSQLCache(ctx, cfg, pool, "frankerfacez:emote", resolver.NewResponseMarshaller(emoteLoader), 1*time.Hour),
+		emoteCache: cache.NewPostgreSQLCache(
+			ctx, cfg, pool, cache.NewPrefixKeyProvider("frankerfacez:emote"),
+			resolver.NewResponseMarshaller(emoteLoader), 1*time.Hour),
 	}
 
 	return r

internal/resolvers/imgur/resolver.go

@@ -45,7 +45,9 @@ func NewResolver(ctx context.Context, cfg config.APIConfig, pool db.Pool, imgurC
 	}
 
 	r := &Resolver{
-		imgurCache: cache.NewPostgreSQLCache(ctx, cfg, pool, "imgur", resolver.NewResponseMarshaller(loader), 1*time.Hour),
+		imgurCache: cache.NewPostgreSQLCache(
+			ctx, cfg, pool, cache.NewPrefixKeyProvider("imgur"),
+			resolver.NewResponseMarshaller(loader), 1*time.Hour),
 	}
 
 	return r

internal/resolvers/livestreamfails/clip_resolver.go

@@ -51,7 +51,9 @@ func NewClipResolver(ctx context.Context, cfg config.APIConfig, pool db.Pool, ap
 	}
 
 	r := &ClipResolver{
-		clipCache: cache.NewPostgreSQLCache(ctx, cfg, pool, "livestreamfails:clip", resolver.NewResponseMarshaller(clipLoader), 1*time.Hour),
+		clipCache: cache.NewPostgreSQLCache(
+			ctx, cfg, pool, cache.NewPrefixKeyProvider("livestreamfails:clip"),
+			resolver.NewResponseMarshaller(clipLoader), 1*time.Hour),
 	}
 
 	return r

internal/resolvers/oembed/resolver.go

@@ -55,8 +55,11 @@ func NewResolver(ctx context.Context, cfg config.APIConfig, pool db.Pool, data [
 	}
 
 	r := &Resolver{
-		oEmbedCache: cache.NewPostgreSQLCache(ctx, cfg, pool, "oembed", resolver.NewResponseMarshaller(loader), 1*time.Hour),
-		oEmbed:      oEmbed,
+		oEmbedCache: cache.NewPostgreSQLCache(
+			ctx, cfg, pool, cache.NewPrefixKeyProvider("oembed"),
+			resolver.NewResponseMarshaller(loader), 1*time.Hour,
+		),
+		oEmbed: oEmbed,
 	}
 
 	return r, nil

internal/resolvers/seventv/emote_resolver.go

@@ -43,7 +43,9 @@ func NewEmoteResolver(ctx context.Context, cfg config.APIConfig, pool db.Pool, a
 	emoteLoader := NewEmoteLoader(cfg, apiURL)
 
 	r := &EmoteResolver{
-		emoteCache: cache.NewPostgreSQLCache(ctx, cfg, pool, "seventv:emote", resolver.NewResponseMarshaller(emoteLoader), 1*time.Hour),
+		emoteCache: cache.NewPostgreSQLCache(
+			ctx, cfg, pool, cache.NewPrefixKeyProvider("seventv:emote"),
+			resolver.NewResponseMarshaller(emoteLoader), 1*time.Hour),
 	}
 
 	return r

internal/resolvers/supinic/track_resolver.go

@@ -48,7 +48,9 @@ func NewTrackResolver(ctx context.Context, cfg config.APIConfig, pool db.Pool) *
 	trackLoader := &TrackLoader{}
 
 	r := &TrackResolver{
-		trackCache: cache.NewPostgreSQLCache(ctx, cfg, pool, "supinic:track", resolver.NewResponseMarshaller(trackLoader), 1*time.Hour),
+		trackCache: cache.NewPostgreSQLCache(
+			ctx, cfg, pool, cache.NewPrefixKeyProvider("supinic:track"),
+			resolver.NewResponseMarshaller(trackLoader), 1*time.Hour),
 	}
 
 	return r

internal/resolvers/twitch/clip_resolver.go

@@ -13,9 +13,7 @@ import (
 	"github.com/Chatterino/api/pkg/resolver"
 )
 
-var (
-	clipSlugRegex = regexp.MustCompile(`^\/(\w{2,25}\/clip\/)?(clip\/)?([a-zA-Z0-9]+(?:-[-\w]{16})?)$`)
-)
+var clipSlugRegex = regexp.MustCompile(`^\/(\w{2,25}\/clip\/)?(clip\/)?([a-zA-Z0-9]+(?:-[-\w]{16})?)$`)
 
 type ClipResolver struct {
 	clipCache cache.Cache
@@ -76,7 +74,10 @@ func NewClipResolver(ctx context.Context, cfg config.APIConfig, pool db.Pool, he
 	}
 
 	r := &ClipResolver{
-		clipCache: cache.NewPostgreSQLCache(ctx, cfg, pool, "twitch:clip", resolver.NewResponseMarshaller(clipLoader), 1*time.Hour),
+		clipCache: cache.NewPostgreSQLCache(
+			ctx, cfg, pool, cache.NewPrefixKeyProvider("twitch:clip"),
+			resolver.NewResponseMarshaller(clipLoader), 1*time.Hour,
+		),
 	}
 
 	return r