Fix hang issue by moving loop logic into separate function to catch all errors.

src/mpvctl/mpvctl.rs

@@ -33,47 +33,12 @@ impl MpvCtl {
 
         tokio::spawn(async move {
             loop {
-                match framed_read.read_frame().await {
-                    Ok(Some(frame)) => {
-                        println!("Read {}", frame);
-                        // get the request id and push the result into the channel
-                        let reqid = {
-                            let obj = match &frame {
-                                serde_json::Value::Object(obj) => obj,
-                                _ => {
-                                    return Err(
-                                        "Got back a json value that wasn't an object.".to_string()
-                                    );
-                                }
-                            };
-                            match obj.get("request_id") {
-                                Some(serde_json::Value::Number(reqid)) if reqid.is_u64() => {
-                                    reqid.as_u64().unwrap()
-                                }
-                                _ => {
-                                    return Err("Unrecognized request_id".to_string());
-                                }
-                            }
-                        };
-
-                        {
-                            let mut db_handle = read_db_handle.lock().unwrap();
-                            if let Entry::Occupied(o) = (*db_handle).entry(reqid) {
-                                o.remove()
-                                    .send(frame)
-                                    .map_err(|e| "Failed to send frame".to_string())?;
-                            } else {
-                                return Err("No entry found for request id".to_string());
-                            }
-                        }
-                    }
-                    Ok(None) => {
-                        return Ok(());
-                    }
+                match Self::read_loop(&mut framed_read, &read_db_handle).await {
+                    Ok(_) => (),
                     Err(e) => {
-                        return Err("Ran into a problem".to_string());
+                        eprintln!("Error in read loop: {}", e);
                     }
-                }
+                };
             }
         });
 
@@ -84,6 +49,52 @@ impl MpvCtl {
         })
     }
 
+    async fn read_loop(
+        framed_read: &mut MpvFramed,
+        db: &CommandDb,
+    ) -> Result<(), Box<dyn std::error::Error>> {
+        match framed_read.read_frame().await {
+            Ok(Some(frame)) => {
+                println!("Read {}", frame);
+                // get the request id and push the result into the channel
+                let reqid = {
+                    let obj = match &frame {
+                        serde_json::Value::Object(obj) => obj,
+                        _ => {
+                            return Err("Got back a json value that wasn't an object.".into());
+                        }
+                    };
+                    match obj.get("request_id") {
+                        Some(serde_json::Value::Number(reqid)) if reqid.is_u64() => {
+                            reqid.as_u64().unwrap()
+                        }
+                        _ => {
+                            return Err("Unrecognized request_id".into());
+                        }
+                    }
+                };
+
+                {
+                    let mut db_handle = db.lock().unwrap();
+                    if let Entry::Occupied(o) = (*db_handle).entry(reqid) {
+                        o.remove()
+                            .send(frame)
+                            .map_err(|e| "Failed to send frame".to_string())?;
+                    } else {
+                        return Err("No entry found for request id".into());
+                    }
+                }
+            }
+            Ok(None) => {
+                return Ok(());
+            }
+            Err(e) => {
+                return Err("Ran into a problem".into());
+            }
+        }
+        Ok(())
+    }
+
     fn grab_request_id(&mut self) -> u64 {
         let ret = self.next_request_id;
         self.next_request_id += 1;