devtools: Don't panic when sending to a disconnected client fails.

components/devtools/actors/browsing_context.rs

@@ -160,7 +160,7 @@ impl Actor for BrowsingContextActor {
                         }
                     }
                 }
-                stream.write_json_packet(&ReconfigureReply { from: self.name() });
+                let _ = stream.write_json_packet(&ReconfigureReply { from: self.name() });
                 ActorMessageStatus::Processed
             },
 
@@ -215,7 +215,7 @@ impl Actor for BrowsingContextActor {
                         title: self.title.borrow().clone(),
                     }],
                 };
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
 

components/devtools/actors/console.rs

@@ -380,7 +380,7 @@ impl Actor for ConsoleActor {
                     from: self.name(),
                     messages: messages,
                 };
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
 
@@ -396,7 +396,7 @@ impl Actor for ConsoleActor {
                         .collect(),
                     traits: StartedListenersTraits,
                 };
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
 
@@ -413,7 +413,7 @@ impl Actor for ConsoleActor {
                         .map(|listener| listener.as_str().unwrap().to_owned())
                         .collect(),
                 };
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
 
@@ -425,13 +425,13 @@ impl Actor for ConsoleActor {
                     matches: vec![],
                     matchProp: "".to_owned(),
                 };
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
 
             "evaluateJS" => {
                 let msg = self.evaluateJS(&registry, &msg);
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
 
@@ -443,7 +443,9 @@ impl Actor for ConsoleActor {
                 };
                 // Emit an eager reply so that the client starts listening
                 // for an async event with the resultID
-                stream.write_json_packet(&early_reply);
+                if stream.write_json_packet(&early_reply).is_err() {
+                    return Ok(ActorMessageStatus::Processed);
+                }
 
                 if msg.get("eager").and_then(|v| v.as_bool()).unwrap_or(false) {
                     // We don't support the side-effect free evaluation that eager evalaution
@@ -464,7 +466,7 @@ impl Actor for ConsoleActor {
                     helperResult: reply.helperResult,
                 };
                 // Send the data from evaluateJS along with a resultID
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
 
@@ -473,7 +475,7 @@ impl Actor for ConsoleActor {
                     from: self.name(),
                     updated: vec![],
                 };
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
 

components/devtools/actors/device.rs

@@ -44,7 +44,7 @@ impl Actor for DeviceActor {
                         platformVersion: "71.0".to_string(),
                     },
                 };
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
 

components/devtools/actors/inspector.rs

@@ -72,13 +72,13 @@ impl Actor for HighlighterActor {
         Ok(match msg_type {
             "showBoxModel" => {
                 let msg = ShowBoxModelReply { from: self.name() };
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
 
             "hideBoxModel" => {
                 let msg = HideBoxModelReply { from: self.name() };
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
 
@@ -123,7 +123,7 @@ impl Actor for NodeActor {
                     ))
                     .unwrap();
                 let reply = ModifyAttributeReply { from: self.name() };
-                stream.write_json_packet(&reply);
+                let _ = stream.write_json_packet(&reply);
                 ActorMessageStatus::Processed
             },
 
@@ -293,7 +293,7 @@ impl Actor for WalkerActor {
         Ok(match msg_type {
             "querySelector" => {
                 let msg = QuerySelectorReply { from: self.name() };
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
 
@@ -310,13 +310,13 @@ impl Actor for WalkerActor {
                     from: self.name(),
                     node: node,
                 };
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
 
             "clearPseudoClassLocks" => {
                 let msg = ClearPseudoclassesReply { from: self.name() };
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
 
@@ -343,7 +343,7 @@ impl Actor for WalkerActor {
                         .collect(),
                     from: self.name(),
                 };
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
 
@@ -481,7 +481,7 @@ impl Actor for PageStyleActor {
                     sheets: vec![],
                     from: self.name(),
                 };
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
 
@@ -491,7 +491,7 @@ impl Actor for PageStyleActor {
                     computed: vec![],
                     from: self.name(),
                 };
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
 
@@ -576,7 +576,7 @@ impl Actor for PageStyleActor {
                 };
                 let msg = serde_json::to_string(&msg).unwrap();
                 let msg = serde_json::from_str::<Value>(&msg).unwrap();
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
 
@@ -625,7 +625,7 @@ impl Actor for InspectorActor {
                         root: node,
                     },
                 };
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
 
@@ -647,7 +647,7 @@ impl Actor for InspectorActor {
                         actor: self.pageStyle.borrow().clone().unwrap(),
                     },
                 };
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
 
@@ -670,7 +670,7 @@ impl Actor for InspectorActor {
                         actor: self.highlighter.borrow().clone().unwrap(),
                     },
                 };
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
 

components/devtools/actors/network_event.rs

@@ -201,7 +201,7 @@ impl Actor for NetworkEventActor {
                     headerSize: headersSize,
                     rawHeaders: rawHeadersString,
                 };
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
             "getRequestCookies" => {
@@ -217,7 +217,7 @@ impl Actor for NetworkEventActor {
                     from: self.name(),
                     cookies: cookies,
                 };
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
             "getRequestPostData" => {
@@ -226,7 +226,7 @@ impl Actor for NetworkEventActor {
                     postData: self.request.body.clone(),
                     postDataDiscarded: false,
                 };
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
             "getResponseHeaders" => {
@@ -251,7 +251,7 @@ impl Actor for NetworkEventActor {
                         headerSize: headersSize,
                         rawHeaders: rawHeadersString,
                     };
-                    stream.write_json_packet(&msg);
+                    let _ = stream.write_json_packet(&msg);
                 }
                 ActorMessageStatus::Processed
             },
@@ -268,7 +268,7 @@ impl Actor for NetworkEventActor {
                     from: self.name(),
                     cookies: cookies,
                 };
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
             "getResponseContent" => {
@@ -277,7 +277,7 @@ impl Actor for NetworkEventActor {
                     content: self.response.body.clone(),
                     contentDiscarded: self.response.body.is_none(),
                 };
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
             "getEventTimings" => {
@@ -297,7 +297,7 @@ impl Actor for NetworkEventActor {
                     timings: timingsObj,
                     totalTime: total,
                 };
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
             "getSecurityInfo" => {
@@ -308,7 +308,7 @@ impl Actor for NetworkEventActor {
                         state: "insecure".to_owned(),
                     },
                 };
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
             _ => ActorMessageStatus::Ignored,

components/devtools/actors/performance.rs

@@ -72,7 +72,7 @@ impl Actor for PerformanceActor {
                         },
                     },
                 };
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
             "canCurrentlyRecord" => {
@@ -83,7 +83,7 @@ impl Actor for PerformanceActor {
                         errors: vec![],
                     },
                 };
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
             _ => ActorMessageStatus::Ignored,

components/devtools/actors/preference.rs

@@ -35,7 +35,7 @@ impl Actor for PreferenceActor {
                     from: self.name(),
                     value: false,
                 };
-                stream.write_json_packet(&reply);
+                let _ = stream.write_json_packet(&reply);
                 ActorMessageStatus::Processed
             },
 
@@ -44,7 +44,7 @@ impl Actor for PreferenceActor {
                     from: self.name(),
                     value: "".to_owned(),
                 };
-                stream.write_json_packet(&reply);
+                let _ = stream.write_json_packet(&reply);
                 ActorMessageStatus::Processed
             },
 
@@ -53,7 +53,7 @@ impl Actor for PreferenceActor {
                     from: self.name(),
                     value: 0,
                 };
-                stream.write_json_packet(&reply);
+                let _ = stream.write_json_packet(&reply);
                 ActorMessageStatus::Processed
             },
 

components/devtools/actors/process.rs

@@ -41,7 +41,7 @@ impl Actor for ProcessActor {
                     from: self.name(),
                     workers: vec![],
                 };
-                stream.write_json_packet(&reply);
+                let _ = stream.write_json_packet(&reply);
                 ActorMessageStatus::Processed
             },
 

components/devtools/actors/root.rs

@@ -131,7 +131,7 @@ impl Actor for RootActor {
                     from: "root".to_owned(),
                     addons: vec![],
                 };
-                stream.write_json_packet(&actor);
+                let _ = stream.write_json_packet(&actor);
                 ActorMessageStatus::Processed
             },
 
@@ -144,7 +144,7 @@ impl Actor for RootActor {
                         isParent: true,
                     }],
                 };
-                stream.write_json_packet(&reply);
+                let _ = stream.write_json_packet(&reply);
                 ActorMessageStatus::Processed
             },
 
@@ -157,7 +157,7 @@ impl Actor for RootActor {
                         isParent: true,
                     },
                 };
-                stream.write_json_packet(&reply);
+                let _ = stream.write_json_packet(&reply);
                 ActorMessageStatus::Processed
             },
 
@@ -169,7 +169,7 @@ impl Actor for RootActor {
                     deviceActor: self.device.clone(),
                     preferenceActor: self.preference.clone(),
                 };
-                stream.write_json_packet(&actor);
+                let _ = stream.write_json_packet(&actor);
                 ActorMessageStatus::Processed
             },
 
@@ -188,7 +188,7 @@ impl Actor for RootActor {
                         })
                         .collect(),
                 };
-                stream.write_json_packet(&actor);
+                let _ = stream.write_json_packet(&actor);
                 ActorMessageStatus::Processed
             },
 
@@ -197,7 +197,7 @@ impl Actor for RootActor {
                     from: self.name(),
                     registrations: vec![],
                 };
-                stream.write_json_packet(&reply);
+                let _ = stream.write_json_packet(&reply);
                 ActorMessageStatus::Processed
             },
 
@@ -210,7 +210,7 @@ impl Actor for RootActor {
                         .map(|name| registry.find::<WorkerActor>(name).encodable())
                         .collect(),
                 };
-                stream.write_json_packet(&reply);
+                let _ = stream.write_json_packet(&reply);
                 ActorMessageStatus::Processed
             },
 
@@ -220,7 +220,7 @@ impl Actor for RootActor {
                     from: self.name(),
                     tab: tab.encodable(&registry),
                 };
-                stream.write_json_packet(&reply);
+                let _ = stream.write_json_packet(&reply);
                 ActorMessageStatus::Processed
             },
 
@@ -232,7 +232,7 @@ impl Actor for RootActor {
                         device: DeviceActor::description(),
                     },
                 };
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
 

components/devtools/actors/stylesheets.rs

@@ -34,7 +34,7 @@ impl Actor for StyleSheetsActor {
                     from: self.name(),
                     styleSheets: vec![],
                 };
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
 

components/devtools/actors/tab.rs

@@ -54,7 +54,7 @@ impl Actor for TabDescriptorActor {
                 let frame = registry
                     .find::<BrowsingContextActor>(&self.browsing_context_actor)
                     .encodable();
-                stream.write_json_packet(&GetTargetReply {
+                let _ = stream.write_json_packet(&GetTargetReply {
                     from: self.name(),
                     frame,
                 });

components/devtools/actors/thread.rs

@@ -100,8 +100,8 @@ impl Actor for ThreadActor {
                         type_: "attached".to_owned(),
                     },
                 };
-                stream.write_json_packet(&msg);
-                stream.write_json_packet(&VoidAttachedReply { from: self.name() });
+                let _ = stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&VoidAttachedReply { from: self.name() });
                 ActorMessageStatus::Processed
             },
 
@@ -110,8 +110,8 @@ impl Actor for ThreadActor {
                     from: self.name(),
                     type_: "resumed".to_owned(),
                 };
-                stream.write_json_packet(&msg);
-                stream.write_json_packet(&VoidAttachedReply { from: self.name() });
+                let _ = stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&VoidAttachedReply { from: self.name() });
                 ActorMessageStatus::Processed
             },
 
@@ -120,12 +120,12 @@ impl Actor for ThreadActor {
                     from: self.name(),
                     type_: "interrupted".to_owned(),
                 };
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
 
             "reconfigure" => {
-                stream.write_json_packet(&ReconfigureReply { from: self.name() });
+                let _ = stream.write_json_packet(&ReconfigureReply { from: self.name() });
                 ActorMessageStatus::Processed
             },
 
@@ -134,7 +134,7 @@ impl Actor for ThreadActor {
                     from: self.name(),
                     sources: vec![],
                 };
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
 

components/devtools/actors/timeline.rs

@@ -14,6 +14,7 @@ use msg::constellation_msg::PipelineId;
 use serde::{Serialize, Serializer};
 use serde_json::{Map, Value};
 use std::cell::RefCell;
+use std::error::Error;
 use std::net::TcpStream;
 use std::sync::{Arc, Mutex};
 use std::thread;
@@ -166,7 +167,9 @@ impl TimelineActor {
                 while let Ok(Some(marker)) = receiver.try_recv() {
                     markers.push(emitter.marker(marker));
                 }
-                emitter.send(markers);
+                if emitter.send(markers).is_err() {
+                    break;
+                }
 
                 thread::sleep(Duration::from_millis(DEFAULT_TIMELINE_DATA_PULL_TIMEOUT));
             })
@@ -235,7 +238,7 @@ impl Actor for TimelineActor {
                     from: self.name(),
                     value: HighResolutionStamp::new(registry.start_stamp(), PreciseTime::now()),
                 };
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
 
@@ -245,7 +248,7 @@ impl Actor for TimelineActor {
                     value: HighResolutionStamp::new(registry.start_stamp(), PreciseTime::now()),
                 };
 
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 self.script_sender
                     .send(DropTimelineMarkers(
                         self.pipeline,
@@ -272,7 +275,7 @@ impl Actor for TimelineActor {
                     value: self.is_recording.lock().unwrap().clone(),
                 };
 
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
 
@@ -311,7 +314,7 @@ impl Emitter {
         }
     }
 
-    fn send(&mut self, markers: Vec<TimelineMarkerReply>) {
+    fn send(&mut self, markers: Vec<TimelineMarkerReply>) -> Result<(), Box<dyn Error>> {
         let end_time = PreciseTime::now();
         let reply = MarkersEmitterReply {
             type_: "markers".to_owned(),
@@ -319,7 +322,7 @@ impl Emitter {
             from: self.from.clone(),
             endTime: HighResolutionStamp::new(self.start_stamp, end_time),
         };
-        self.stream.write_json_packet(&reply);
+        self.stream.write_json_packet(&reply)?;
 
         if let Some(ref actor_name) = self.framerate_actor {
             let mut lock = self.registry.lock();
@@ -331,7 +334,7 @@ impl Emitter {
                 delta: HighResolutionStamp::new(self.start_stamp, end_time),
                 timestamps: framerate_actor.take_pending_ticks(),
             };
-            self.stream.write_json_packet(&framerateReply);
+            self.stream.write_json_packet(&framerateReply)?;
         }
 
         if let Some(ref actor_name) = self.memory_actor {
@@ -343,7 +346,9 @@ impl Emitter {
                 delta: HighResolutionStamp::new(self.start_stamp, end_time),
                 measurement: memory_actor.measure(),
             };
-            self.stream.write_json_packet(&memoryReply);
+            self.stream.write_json_packet(&memoryReply)?;
         }
+
+        Ok(())
     }
 }

components/devtools/actors/worker.rs

@@ -82,7 +82,7 @@ impl Actor for WorkerActor {
                     threadActor: self.thread.clone(),
                     consoleActor: self.console.clone(),
                 };
-                stream.write_json_packet(&msg);
+                let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
 

components/devtools/lib.rs

@@ -193,7 +193,10 @@ fn run_server(
         {
             let actors = actors.lock().unwrap();
             let msg = actors.find::<RootActor>("root").encodable();
-            stream.write_json_packet(&msg);
+            if let Err(e) = stream.write_json_packet(&msg) {
+                warn!("Error writing response: {:?}", e);
+                return;
+            }
         }
 
         'outer: loop {
@@ -451,7 +454,7 @@ fn run_server(
                     eventActor: actor.event_actor(),
                 };
                 for stream in &mut connections {
-                    stream.write_json_packet(&msg);
+                    let _ = stream.write_json_packet(&msg);
                 }
             },
             NetworkEvent::HttpResponse(httpresponse) => {
@@ -464,7 +467,7 @@ fn run_server(
                     updateType: "requestHeaders".to_owned(),
                 };
                 for stream in &mut connections {
-                    stream.write_merged_json_packet(&msg, &actor.request_headers());
+                    let _ = stream.write_merged_json_packet(&msg, &actor.request_headers());
                 }
 
                 let msg = NetworkEventUpdateMsg {
@@ -473,7 +476,7 @@ fn run_server(
                     updateType: "requestCookies".to_owned(),
                 };
                 for stream in &mut connections {
-                    stream.write_merged_json_packet(&msg, &actor.request_cookies());
+                    let _ = stream.write_merged_json_packet(&msg, &actor.request_cookies());
                 }
 
                 //Send a networkEventUpdate (responseStart) to the client
@@ -485,7 +488,7 @@ fn run_server(
                 };
 
                 for stream in &mut connections {
-                    stream.write_json_packet(&msg);
+                    let _ = stream.write_json_packet(&msg);
                 }
                 let msg = NetworkEventUpdateMsg {
                     from: netevent_actor_name.clone(),
@@ -496,7 +499,7 @@ fn run_server(
                     totalTime: actor.total_time(),
                 };
                 for stream in &mut connections {
-                    stream.write_merged_json_packet(&msg, &extra);
+                    let _ = stream.write_merged_json_packet(&msg, &extra);
                 }
 
                 let msg = NetworkEventUpdateMsg {
@@ -508,7 +511,7 @@ fn run_server(
                     state: "insecure".to_owned(),
                 };
                 for stream in &mut connections {
-                    stream.write_merged_json_packet(&msg, &extra);
+                    let _ = stream.write_merged_json_packet(&msg, &extra);
                 }
 
                 let msg = NetworkEventUpdateMsg {
@@ -517,7 +520,7 @@ fn run_server(
                     updateType: "responseContent".to_owned(),
                 };
                 for stream in &mut connections {
-                    stream.write_merged_json_packet(&msg, &actor.response_content());
+                    let _ = stream.write_merged_json_packet(&msg, &actor.response_content());
                 }
 
                 let msg = NetworkEventUpdateMsg {
@@ -526,7 +529,7 @@ fn run_server(
                     updateType: "responseCookies".to_owned(),
                 };
                 for stream in &mut connections {
-                    stream.write_merged_json_packet(&msg, &actor.response_cookies());
+                    let _ = stream.write_merged_json_packet(&msg, &actor.response_cookies());
                 }
 
                 let msg = NetworkEventUpdateMsg {
@@ -535,7 +538,7 @@ fn run_server(
                     updateType: "responseHeaders".to_owned(),
                 };
                 for stream in &mut connections {
-                    stream.write_merged_json_packet(&msg, &actor.response_headers());
+                    let _ = stream.write_merged_json_packet(&msg, &actor.response_headers());
                 }
             },
         }

components/devtools/protocol.rs

@@ -8,6 +8,7 @@
 
 use serde::Serialize;
 use serde_json::{self, Value};
+use std::error::Error;
 use std::io::{Read, Write};
 use std::net::TcpStream;
 
@@ -26,29 +27,38 @@ pub struct Method {
 }
 
 pub trait JsonPacketStream {
-    fn write_json_packet<T: Serialize>(&mut self, obj: &T);
-    fn write_merged_json_packet<T: Serialize, U: Serialize>(&mut self, base: &T, extra: &U);
+    fn write_json_packet<T: Serialize>(&mut self, obj: &T) -> Result<(), Box<dyn Error>>;
+    fn write_merged_json_packet<T: Serialize, U: Serialize>(
+        &mut self,
+        base: &T,
+        extra: &U,
+    ) -> Result<(), Box<dyn Error>>;
     fn read_json_packet(&mut self) -> Result<Option<Value>, String>;
 }
 
 impl JsonPacketStream for TcpStream {
-    fn write_json_packet<T: Serialize>(&mut self, obj: &T) {
-        let s = serde_json::to_string(obj).unwrap();
+    fn write_json_packet<T: Serialize>(&mut self, obj: &T) -> Result<(), Box<dyn Error>> {
+        let s = serde_json::to_string(obj)?;
         debug!("<- {}", s);
-        write!(self, "{}:{}", s.len(), s).unwrap();
+        write!(self, "{}:{}", s.len(), s)?;
+        Ok(())
     }
 
-    fn write_merged_json_packet<T: Serialize, U: Serialize>(&mut self, base: &T, extra: &U) {
-        let mut obj = serde_json::to_value(base).unwrap();
+    fn write_merged_json_packet<T: Serialize, U: Serialize>(
+        &mut self,
+        base: &T,
+        extra: &U,
+    ) -> Result<(), Box<dyn Error>> {
+        let mut obj = serde_json::to_value(base)?;
         let obj = obj.as_object_mut().unwrap();
-        let extra = serde_json::to_value(extra).unwrap();
+        let extra = serde_json::to_value(extra)?;
         let extra = extra.as_object().unwrap();
 
         for (key, value) in extra {
             obj.insert(key.to_owned(), value.to_owned());
         }
 
-        self.write_json_packet(obj);
+        self.write_json_packet(obj)
     }
 
     fn read_json_packet(&mut self) -> Result<Option<Value>, String> {
@@ -74,7 +84,9 @@ impl JsonPacketStream for TcpStream {
                         Err(_) => return Err("packet length missing / not parsable".to_owned()),
                     };
                     let mut packet = String::new();
-                    self.take(packet_len).read_to_string(&mut packet).unwrap();
+                    self.take(packet_len)
+                        .read_to_string(&mut packet)
+                        .map_err(|e| e.to_string())?;
                     debug!("{}", packet);
                     return match serde_json::from_str(&packet) {
                         Ok(json) => Ok(Some(json)),