feat: add custom error handler (#285)

* improvement: replace lib

* improvement: replace router for services

* feat: replace async routes

* feat: add custom error handler

lib/server.js

@@ -149,29 +149,32 @@ class CampsiServer extends MQTTEmitter {
     this.app.use((req, res, next) => {
       res.status(404).json({ message: `Can't find ${req.method} ${req.path}` });
     });
-
-    this.app.use((err, req, res, next) => {
-      if (res.headersSent) {
-        return next(err);
-      }
-
-      // An error may happen in a middleware registred before the pino middleware.
-      if (req.log) {
-        req.log.error(err, err.message);
-      } else {
-        this.logger.error(err, err.message);
-      }
-
-      if (err instanceof ValidationError) {
-        return res.status(400).send(err.validationErrors);
-      }
-
-      const { message, status } = err;
-      res.status(status || 500).json({
-        message,
-        stack: process.env.NODE_ENV !== 'production' ? err.stack : undefined
+    if (this.config.errorHandler) {
+      this.app.use(this.config.errorHandler(this));
+    } else {
+      this.app.use((err, req, res, next) => {
+        if (res.headersSent) {
+          return next(err);
+        }
+
+        // An error may happen in a middleware registred before the pino middleware.
+        if (req.log) {
+          req.log.error(err, err.message);
+        } else {
+          this.logger.error(err, err.message);
+        }
+
+        if (err instanceof ValidationError) {
+          return res.status(400).send(err.validationErrors);
+        }
+
+        const { message, status } = err;
+        res.status(status || 500).json({
+          message,
+          stack: process.env.NODE_ENV !== 'production' ? err.stack : undefined
+        });
       });
-    });
+    }
     this.emit('campsi/ready');
   }
 }