From 55ef904286be426450b66be3b8754bd9faa0a2ce Mon Sep 17 00:00:00 2001
From: Jan-Lukas Else <mail@jlelse.de>
Date: Sat, 13 Nov 2021 20:40:25 +0100
Subject: [PATCH] Fix

---
 geoMap.go                     | 28 ++++++++++++++++++----------
 templates/assets/js/geomap.js |  4 ++--
 2 files changed, 20 insertions(+), 12 deletions(-)

diff --git a/geoMap.go b/geoMap.go
index 6a9edda..855039c 100644
--- a/geoMap.go
+++ b/geoMap.go
@@ -61,16 +61,24 @@ func (a *goBlog) serveGeoMap(w http.ResponseWriter, r *http.Request) {
 		}
 	}
 
-	locationsJsonBytes, err := json.Marshal(locations)
-	if err != nil {
-		a.serveError(w, r, err.Error(), http.StatusInternalServerError)
-		return
+	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)
 	}
 
-	tracksJsonBytes, err := json.Marshal(tracks)
-	if err != nil {
-		a.serveError(w, r, err.Error(), http.StatusInternalServerError)
-		return
+	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))
@@ -78,8 +86,8 @@ func (a *goBlog) serveGeoMap(w http.ResponseWriter, r *http.Request) {
 		BlogString: blog,
 		Canonical:  a.getFullAddress(mapPath),
 		Data: map[string]interface{}{
-			"locations": string(locationsJsonBytes),
-			"tracks":    string(tracksJsonBytes),
+			"locations": locationsJson,
+			"tracks":    tracksJson,
 		},
 	})
 }
diff --git a/templates/assets/js/geomap.js b/templates/assets/js/geomap.js
index 9258f33..e8eca8c 100644
--- a/templates/assets/js/geomap.js
+++ b/templates/assets/js/geomap.js
@@ -1,7 +1,7 @@
 (function () {
     let mapEl = document.getElementById('map')
-    let locations = JSON.parse(mapEl.dataset.locations)
-    let tracks = JSON.parse(mapEl.dataset.tracks)
+    let locations = (mapEl.dataset.locations == "") ? [] : JSON.parse(mapEl.dataset.locations)
+    let tracks = (mapEl.dataset.tracks == "") ? [] : JSON.parse(mapEl.dataset.tracks)
 
     let map = L.map('map')