feat(server): ✨ detect MIME type from file headers

server/pkg/apis/files.go

@@ -1,8 +1,10 @@
 package apis
 
 import (
+	"mime"
 	"mime/multipart"
 	"net/http"
+	"path/filepath"
 
 	"github.com/labstack/echo/v5"
 	"github.com/pocketbase/pocketbase/apis"
@@ -12,9 +14,28 @@ import (
 	"github.com/pocketbase/pocketbase/tools/filesystem"
 )
 
+const ApplicationOctetStream = "application/octet-stream"
+
 func newFile(app core.App, files *models.Collection, author *models.Record, file *multipart.FileHeader) (*models.Record, error) {
 	f, err := filesystem.NewFileFromMultipart(file)
 
+	var contentType string
+
+	if ct := file.Header.Get("Content-Type"); ct != "" {
+		contentType = ct
+	}
+
+	// Guess content-type from extension if missing
+	if contentType == "" || contentType == ApplicationOctetStream {
+		if ext := filepath.Ext(file.Filename); ext != "" {
+			contentType = mime.TypeByExtension(ext)
+		}
+	}
+
+	if contentType == "" {
+		contentType = ApplicationOctetStream
+	}
+
 	if err != nil {
 		return nil, apis.NewApiError(http.StatusInternalServerError, "", err)
 	}
@@ -27,6 +48,7 @@ func newFile(app core.App, files *models.Collection, author *models.Record, file
 		"author":          author.Id,
 		"tags":            "[]",
 		"tagsSuggestions": "[]",
+		"type":            contentType,
 	})
 	form.AddFiles("file", f)