Add a config for blurhash

api/custom/version.go

@@ -9,13 +9,14 @@ import (
 )
 
 func GetVersion(r *http.Request, rctx rcontext.RequestContext, user api.UserInfo) interface{} {
+	unstableFeatures := make(map[string]bool)
+	unstableFeatures["xyz.amorgan.blurhash"] = rctx.Config.Features.MSC2448Blurhash.Enabled
+
 	return &api.DoNotCacheResponse{
 		Payload: map[string]interface{}{
-			"Version":   version.Version,
-			"GitCommit": version.GitCommit,
-			"unstable_features": []string{
-				"xyz.amorgan.blurhash",
-			},
+			"Version":           version.Version,
+			"GitCommit":         version.GitCommit,
+			"unstable_features": unstableFeatures,
 		},
 	}
 }

api/r0/upload.go

@@ -58,13 +58,19 @@ func UploadMedia(r *http.Request, rctx rcontext.RequestContext, user api.UserInf
 		return api.InternalServerError("Unexpected Error")
 	}
 
-	hash, err := info_controller.GetOrCalculateBlurhash(media, rctx)
-	if err != nil {
-		rctx.Log.Warn("Failed to calculate blurhash: " + err.Error())
+	if rctx.Config.Features.MSC2448Blurhash.Enabled {
+		hash, err := info_controller.GetOrCalculateBlurhash(media, rctx)
+		if err != nil {
+			rctx.Log.Warn("Failed to calculate blurhash: " + err.Error())
+		}
+
+		return &MediaUploadedResponse{
+			ContentUri: media.MxcUri(),
+			Blurhash:   hash,
+		}
 	}
 
 	return &MediaUploadedResponse{
 		ContentUri: media.MxcUri(),
-		Blurhash:   hash,
 	}
 }

api/webserver/webserver.go

@@ -135,8 +135,9 @@ func Init() *sync.WaitGroup {
 			routes["/_matrix/media/"+version+"/info/{server:[a-zA-Z0-9.:\\-_]+}/{mediaId:[a-zA-Z0-9.\\-_]+}"] = route{"GET", infoHandler}
 			routes["/_matrix/media/"+version+"/download/{server:[a-zA-Z0-9.:\\-_]+}/{mediaId:[a-zA-Z0-9.\\-_]+}"] = route{"DELETE", purgeOneHandler}
 
-			// MSC2448: Blurhash
-			routes["/_matrix/media/"+version+"/xyz.amorgan/upload"] = route{"POST", uploadHandler}
+			if config.Get().Features.MSC2448Blurhash.Enabled {
+				routes["/_matrix/media/"+version+"/xyz.amorgan/upload"] = route{"POST", uploadHandler}
+			}
 		}
 	}
 

common/config/conf_min_shared.go

@@ -7,6 +7,7 @@ type MinimumRepoConfig struct {
 	Identicons     IdenticonsConfig  `yaml:"identicons"`
 	Quarantine     QuarantineConfig  `yaml:"quarantine"`
 	TimeoutSeconds TimeoutsConfig    `yaml:"timeouts"`
+	Features       FeatureConfig     `yaml:"featureSupport"`
 }
 
 func NewDefaultMinimumRepoConfig() MinimumRepoConfig {
@@ -38,5 +39,17 @@ func NewDefaultMinimumRepoConfig() MinimumRepoConfig {
 			ClientServer: 30,
 			Federation:   120,
 		},
+		Features: FeatureConfig{
+			MSC2448Blurhash: MSC2448Config{
+				Enabled:         false,
+				MaxRenderWidth:  1024,
+				MaxRenderHeight: 1024,
+				GenerateWidth:   64,
+				GenerateHeight:  64,
+				XComponents:     4,
+				YComponents:     3,
+				Punch:           1,
+			},
+		},
 	}
 }

common/config/models_domain.go

@@ -72,3 +72,18 @@ type TimeoutsConfig struct {
 	Federation   int `yaml:"federationTimeoutSeconds"`
 	ClientServer int `yaml:"clientServerTimeoutSeconds"`
 }
+
+type FeatureConfig struct {
+	MSC2448Blurhash MSC2448Config `yaml:"MSC2448"`
+}
+
+type MSC2448Config struct {
+	Enabled         bool `yaml:"enabled"`
+	MaxRenderWidth  int  `yaml:"maxWidth"`
+	MaxRenderHeight int  `yaml:"maxHeight"`
+	GenerateWidth   int  `yaml:"thumbWidth"`
+	GenerateHeight  int  `yaml:"thumbHeight"`
+	XComponents     int  `yaml:"xComponents"`
+	YComponents     int  `yaml:"yComponents"`
+	Punch           int  `yaml:"punch"`
+}

common/config/watch.go

@@ -60,7 +60,8 @@ func onFileChanged() {
 	bindPortChange := configNew.General.Port != configNow.General.Port
 	forwardAddressChange := configNew.General.TrustAnyForward != configNow.General.TrustAnyForward
 	forwardedHostChange := configNew.General.UseForwardedHost != configNow.General.UseForwardedHost
-	if bindAddressChange || bindPortChange || forwardAddressChange || forwardedHostChange {
+	featureChanged := hasWebFeatureChanged(configNew, configNow)
+	if bindAddressChange || bindPortChange || forwardAddressChange || forwardedHostChange || featureChanged {
 		logrus.Warn("Webserver configuration changed - remounting")
 		globals.WebReloadChan <- true
 	}
@@ -93,3 +94,11 @@ func onFileChanged() {
 	logrus.Info("Restarting recurring tasks")
 	globals.RecurringTasksReloadChan <- true
 }
+
+func hasWebFeatureChanged(configNew *MainRepoConfig, configNow *MainRepoConfig) bool {
+	if configNew.Features.MSC2448Blurhash.Enabled != configNow.Features.MSC2448Blurhash.Enabled {
+		return true
+	}
+
+	return false
+}

config.sample.yaml

@@ -392,3 +392,28 @@ metrics:
 
   # The port to listen on. Cannot be the same as the general web server port.
   port: 9000
+
+# Options for controlling various MSCs/unstable features of the media repo
+# Sections of this config might disappear or be added over time. By default all
+# features are disabled in here and must be explicitly enabled to be used.
+featureSupport:
+  # MSC2248 - Blurhash
+  MSC2448:
+    # Whether or not this MSC is enabled for use in the media repo
+    enabled: false
+
+    # Maximum dimensions for converting a blurhash to an image
+    maxWidth: 1024
+    maxHeight: 1024
+
+    # Thumbnail size in pixels to use to generate the blurhash string
+    thumbWidth: 64
+    thumbHeight: 64
+
+    # The X and Y components to use. Higher numbers blur less, lower numbers blur more.
+    xComponents: 4
+    yComponents: 3
+
+    # The amount of contrast to apply when converting a blurhash to an image. Lower values
+    # make the effect more subtle, larger values make it stronger.
+    punch: 1

controllers/info_controller/info_controller.go

@@ -40,7 +40,7 @@ func GetOrCalculateBlurhash(media *types.Media, rctx rcontext.RequestContext) (s
 
 	// Resize the image to make the blurhash a bit more reasonable to calculate
 	rctx.Log.Info("Resizing image for blurhash (faster calculation)")
-	smallImg := imaging.Fill(imgSrc, 128, 128, imaging.Center, imaging.Lanczos)
+	smallImg := imaging.Fill(imgSrc, rctx.Config.Features.MSC2448Blurhash.GenerateWidth, rctx.Config.Features.MSC2448Blurhash.GenerateHeight, imaging.Center, imaging.Lanczos)
 	imgBuf := &bytes.Buffer{}
 	err = imaging.Encode(imgBuf, smallImg, imaging.PNG)
 	if err != nil {
@@ -52,7 +52,7 @@ func GetOrCalculateBlurhash(media *types.Media, rctx rcontext.RequestContext) (s
 	}
 
 	rctx.Log.Info("Calculating blurhash")
-	encoded, err := blurhash.Encode(4, 3, &decoded)
+	encoded, err := blurhash.Encode(rctx.Config.Features.MSC2448Blurhash.XComponents, rctx.Config.Features.MSC2448Blurhash.YComponents, &decoded)
 	if err != nil {
 		return "", err
 	}

docs/config.md

@@ -65,3 +65,6 @@ identicons:
 
 Per-domain configs can also be layered - just ensure that each layer has the `homeserver` property in it. They inherit
 from the main config for options not defined in their layers.
+
+Note: all feature configs which require webserver routes to be added will need to be additionally defined in the main 
+config as enabled or disabled, then turned on and off for individual domains.