move connecting and sending to func

src/modem.rs

@@ -483,7 +483,7 @@ impl<UART: serial::Uart> Modem<UART> {
         conn.set_user_name(Some(username.to_string()));
         conn.set_password(Some(password.to_string()));
         let _ = conn.encode(&mut buf)?;
-        self.tcp_manual_send(&mut buf).ok();
+        let _ = self.tcp_manual_send(&mut buf)?;
 
         let reply = self.mqtt_receive_reply()?;
         println!("mqtt decoded packet: ({:?})", reply);
@@ -503,9 +503,7 @@ impl<UART: serial::Uart> Modem<UART> {
             message.as_bytes(),
         );
         let _ = packet.encode(&mut buf)?;
-        println!("created mqtt publish packet ... ({})",
-            std::str::from_utf8(buf.as_slice()).unwrap_or(""));
-        self.tcp_manual_send(&mut buf).ok();
+        self.tcp_manual_send(&mut buf)?;
         Ok(())
     }
 }
@@ -552,8 +550,6 @@ where
     let mqtt_username = include_str!("../secret/username").trim();
     let mqtt_password = include_str!("../secret/password").trim();
 
-    mdm.init(pwrkey, rst, power)?;
-
     // thread::sleep(Duration::from_millis(500));
 
     //println!("setting up client TLS cert");
@@ -564,15 +560,11 @@ where
     //let _ = mdm.ssl_set_client_cert(client_cert_path, "t")?;
     //let _ = mdm.fs_list("C:\\USER\\")?;
 
-    let _ = mdm.echo(false);
-    // Retry 5 times to open a TCP connection, otherwise fail and wait for reboot.
-    let mut retries = 0;
-
-    loop {
+    fn start_sending(mdm: &mut Modem<serial::UART1>, mqtt_username: &str, mqtt_password: &str, receiver: Receiver<Msg>) -> anyhow::Result<()> {
         if !mdm.is_gprs_attached()? {
             let _ = mdm.gprs_attach_ap(crate::config::MTS)?;
+            let _ = mdm.try_connect_gprs()?;
         }
-        if let Ok(()) = mdm.try_connect_gprs() {
         // When command AT+CIPQSEND=0, it is in normal sending mode. In this mode, after user
         // sends data by AT+CIPSEND, if the server receives TCP data, it will give ACK message
         // to module, and the module will respond SEND OK.
@@ -580,10 +572,9 @@ where
         // Enables getting data from network manually.
         let _ = mdm.send("AT+CIPRXGET=1", "OK");
 
-            if let Err(_) = mdm.tcp_connect("51.158.66.64", 7887) {
-                if retries < 5 {
-                    retries += 1;
-                    continue;
+        for _ in 0..5 {
+            if let Ok(_) = mdm.tcp_connect("51.158.66.64", 7887) {
+                break
             }
         }
 
@@ -618,7 +609,14 @@ where
                 }
             }
         };
+
+        Ok(())
+    }
+
+    mdm.init(pwrkey, rst, power)?;
+    let _ = mdm.echo(false)?;
+    let _ = start_sending(&mut mdm, mqtt_username, mqtt_password, receiver)?;
     let _ = mdm.tcp_close_connection()?;
-        }
-    }
+
+    Ok(())
 }