Build for older windows version in CI

.github/workflows/build.yml

@@ -6,7 +6,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu-latest, macos-latest, windows-latest]
+        os: [ubuntu-latest, macos-latest, windows-2019]
     runs-on: ${{ matrix.os }}
 
     steps:

remote_send/src/mqtt_server.rs

@@ -187,11 +187,10 @@ impl Mqtt {
             ),
             id: client.machine_id.to_owned(),
         };
-        let data = serde_json::to_vec(&data).unwrap();
+        let data = serde_json::to_vec(&data)?;
 
         let server = self.server.upgrade().unwrap();
-        server
-            .send_packet(
+        server.send_packet(
             client_id,
             PublishPacket {
                 flags: PublishFlags::QOS1,
@@ -200,8 +199,7 @@ impl Mqtt {
                 data,
             }
             .to_packet(),
-            )
-            .unwrap();
+        )?;
 
         Ok(())
     }