run golangci-lint and apply suggested fixes

daemon/logging/logging_formatters.go

@@ -161,10 +161,16 @@ func (f *LogfmtFormatter) Format(e *logger.Entry) ([]byte, error) {
 	enc := logfmt.NewEncoder(&buf)
 
 	if f.metadataFlags&MetadataTime != 0 {
-		enc.EncodeKeyval(FieldTime, e.Time)
+		err := enc.EncodeKeyval(FieldTime, e.Time)
+		if err != nil {
+			return nil, errors.Wrap(err, "logfmt: encode time")
+		}
 	}
 	if f.metadataFlags&MetadataLevel != 0 {
-		enc.EncodeKeyval(FieldLevel, e.Level)
+		err := enc.EncodeKeyval(FieldLevel, e.Level)
+		if err != nil {
+			return nil, errors.Wrap(err, "logfmt: encode level")
+		}
 	}
 
 	// at least try and put job and task in front
@@ -181,8 +187,10 @@ func (f *LogfmtFormatter) Format(e *logger.Entry) ([]byte, error) {
 		prefixed[pf] = true
 	}
 
-	enc.EncodeKeyval(FieldMessage, e.Message)
-
+	err := enc.EncodeKeyval(FieldMessage, e.Message)
+	if err != nil {
+		return nil, errors.Wrap(err, "logfmt: encode message")
+	}
 	for k, v := range e.Fields {
 		if !prefixed[k] {
 			if err := logfmtTryEncodeKeyval(enc, k, v); err != nil {
@@ -201,7 +209,10 @@ func logfmtTryEncodeKeyval(enc *logfmt.Encoder, field, value interface{}) error
 	case nil: // ok
 		return nil
 	case logfmt.ErrUnsupportedValueType:
-		enc.EncodeKeyval(field, fmt.Sprintf("<%T>", value))
+		err := enc.EncodeKeyval(field, fmt.Sprintf("<%T>", value))
+		if err != nil {
+			return errors.Wrap(err, "cannot encode unsuuported value type Go type")
+		}
 		return nil
 	}
 	return errors.Wrapf(err, "cannot encode field '%s'", field)

daemon/logging/logging_outlets.go

@@ -30,7 +30,10 @@ func (h WriterOutlet) WriteEntry(entry logger.Entry) error {
 		return err
 	}
 	_, err = h.writer.Write(bytes)
-	h.writer.Write([]byte("\n"))
+	if err != nil {
+		return err
+	}
+	_, err = h.writer.Write([]byte("\n"))
 	return err
 }
 
@@ -94,8 +97,10 @@ func (h *TCPOutlet) outLoop(retryInterval time.Duration) {
 				conn = nil
 			}
 		}
-		conn.SetWriteDeadline(time.Now().Add(retryInterval))
-		_, err = io.Copy(conn, msg)
+		err = conn.SetWriteDeadline(time.Now().Add(retryInterval))
+		if err == nil {
+			_, err = io.Copy(conn, msg)
+		}
 		if err != nil {
 			retry = time.Now().Add(retryInterval)
 			conn.Close()