Fix

geoMap.go

@@ -61,25 +61,33 @@ func (a *goBlog) serveGeoMap(w http.ResponseWriter, r *http.Request) {
 		}
 	}
 
+	locationsJson := ""
+	if len(locations) > 0 {
 		locationsJsonBytes, err := json.Marshal(locations)
 		if err != nil {
 			a.serveError(w, r, err.Error(), http.StatusInternalServerError)
 			return
 		}
+		locationsJson = string(locationsJsonBytes)
+	}
 
+	tracksJson := ""
+	if len(tracks) > 0 {
 		tracksJsonBytes, err := json.Marshal(tracks)
 		if err != nil {
 			a.serveError(w, r, err.Error(), http.StatusInternalServerError)
 			return
 		}
+		tracksJson = string(tracksJsonBytes)
+	}
 
 	mapPath := bc.getRelativePath(defaultIfEmpty(bc.Map.Path, defaultGeoMapPath))
 	a.render(w, r, templateGeoMap, &renderData{
 		BlogString: blog,
 		Canonical:  a.getFullAddress(mapPath),
 		Data: map[string]interface{}{
-			"locations": string(locationsJsonBytes),
+			"locations": locationsJson,
-			"tracks":    string(tracksJsonBytes),
+			"tracks":    tracksJson,
 		},
 	})
 }

templates/assets/js/geomap.js

@@ -1,7 +1,7 @@
 (function () {
     let mapEl = document.getElementById('map')
-    let locations = JSON.parse(mapEl.dataset.locations)
+    let locations = (mapEl.dataset.locations == "") ? [] : JSON.parse(mapEl.dataset.locations)
-    let tracks = JSON.parse(mapEl.dataset.tracks)
+    let tracks = (mapEl.dataset.tracks == "") ? [] : JSON.parse(mapEl.dataset.tracks)
 
     let map = L.map('map')