refactor of topic handling and image serving

ui/images.go

@@ -28,6 +28,7 @@ import (
 
 	"git.erbosoft.com/amy/amsterdam/database"
 	"github.com/disintegration/imaging"
+	"github.com/labstack/echo/v4"
 )
 
 //go:embed static_images/*
@@ -55,14 +56,12 @@ func mimeTypeFromFilename(filename string) string {
 
 /* AmServeImage serves an image from internal storage.
  * Parameters:
- *     ctxt - The AmContext for the request.
+ *     c - The Echo context for this request.
  * Returns:
- *     Type of content to be rendered
- *     Content to be rendered
- *     Standard Go error return
+ *     Standard Go error return.
  */
-func AmServeImage(ctxt AmContext) (string, any, error) {
-	components := strings.SplitAfter(ctxt.URLPath(), "/")
+func AmServeImage(c echo.Context) error {
+	components := strings.SplitAfter(c.Request().URL.Path, "/")
 	var err error = nil
 	if len(components) == 4 {
 		switch components[2] {
@@ -70,27 +69,24 @@ func AmServeImage(ctxt AmContext) (string, any, error) {
 			var b []byte
 			b, err = static_images.ReadFile(filepath.Join("static_images", components[3]))
 			if err == nil {
-				ctxt.SetOutputType(mimeTypeFromFilename(components[3]))
-				return "bytes", b, nil
+				return c.Blob(http.StatusOK, mimeTypeFromFilename(components[3]), b)
 			}
 		case "store/":
 			var id int
 			id, err = strconv.Atoi(components[3])
 			if err == nil {
 				var img *database.ImageStore
-				img, err = database.AmLoadImage(ctxt.Ctx(), int32(id))
+				img, err = database.AmLoadImage(c.Request().Context(), int32(id))
 				if err == nil {
-					ctxt.SetOutputType(img.MimeType)
-					return "bytes", img.Data, nil
+					return c.Blob(http.StatusOK, img.MimeType, img.Data)
 				}
 			}
 		}
 	}
-	ctxt.SetRC(http.StatusNotFound)
 	if err == nil {
-		err = fmt.Errorf("image not found: %s", ctxt.URLPath())
+		err = fmt.Errorf("image not found: %s", c.Request().URL.Path)
 	}
-	return ErrorPage(ctxt, err)
+	return c.String(http.StatusNotFound, err.Error())
 }
 
 /* AmProcessUploadedImage takes an image and resizes it to a specified size, returning its data.

ui/middleware.go

@@ -12,8 +12,10 @@ package ui
 
 import (
 	"errors"
+	"fmt"
 	"net/http"
 	"net/url"
+	"strconv"
 
 	"git.erbosoft.com/amy/amsterdam/config"
 	"git.erbosoft.com/amy/amsterdam/database"
@@ -119,6 +121,7 @@ func ValidateConference(next echo.HandlerFunc) echo.HandlerFunc {
 	}
 }
 
+// SetConference is middleware that sets the conference context based on the URL.
 func SetConference(next echo.HandlerFunc) echo.HandlerFunc {
 	return func(c echo.Context) error {
 		ctxt := AmContextFromEchoContext(c)
@@ -140,3 +143,22 @@ func SetConference(next echo.HandlerFunc) echo.HandlerFunc {
 		return next(c)
 	}
 }
+
+// SetTopic is middleware that sets the topic context based on the URL.
+func SetTopic(next echo.HandlerFunc) echo.HandlerFunc {
+	return func(c echo.Context) error {
+		ctxt := AmContextFromEchoContext(c)
+		conf := ctxt.GetScratch("currentConference").(*database.Conference)
+
+		var topic *database.Topic = nil
+		if rawTopic, err := strconv.ParseInt(ctxt.URLParam("topic"), 10, 16); err == nil {
+			topic, err = database.AmGetTopicByNumber(ctxt.Ctx(), conf, int16(rawTopic))
+		}
+		if topic == nil {
+			ctxt.SetRC(http.StatusNotFound)
+			return middlewareErrorPage(c, ctxt, fmt.Errorf("topic not found: %s", ctxt.URLParam("topic")))
+		}
+		ctxt.SetScratch("currentTopic", topic)
+		return next(c)
+	}
+}