From f288f60239e8db5f7d9ee6f3918d70c9d0413ac6 Mon Sep 17 00:00:00 2001
From: Brandon Liu <bdon@bdon.org>
Date: Tue, 8 Jun 2021 18:41:58 +0800
Subject: [PATCH] maplibre: cancel correctly captued in closure [#6]

---
 js/index.src.mjs | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/js/index.src.mjs b/js/index.src.mjs
index b65d9c3..4519a18 100644
--- a/js/index.src.mjs
+++ b/js/index.src.mjs
@@ -206,22 +206,24 @@ export const addProtocol = maplibre_instance => {
         let z = result[2]
         let x = result[3]
         let y = result[4]
-        var cancel = () => {}
+        var cancel = () => { }
         instance.getZxy(+z,+x,+y).then(val => {
             if (val) {
                 let headers = {'Range':'bytes=' + val[0] + '-' + (val[0]+val[1]-1)}
                 const controller = new AbortController()
                 const signal = controller.signal
+                cancel = () => { controller.abort() }
                 fetch(pmtiles_url,{signal:signal,headers:headers}).then(resp => {
                     return resp.arrayBuffer()
                 }).then(arr => {
                     callback(null,arr,null,null)
+                }).catch(e => {
+                    callback(new Error("Canceled"),null,null,null)
                 })
-                cancel = controller.abort
             } else {
                 callback(null,new Uint8Array(),null,null)
             }
         })
-        return { cancel: cancel }
+        return { cancel: () => { cancel() } }
      })
 }