- keep an original error object in error

 - add event handler for taking care lderror in `error` and `unhandledrejection` events

Author: zbryikt

CHANGELOG.md

@@ -1,8 +1,10 @@
 # Change Logs
 
-## v2.2.1 (upcoming)
+## v2.3.0
 
  - add 1028 `resource unavailable`
+ - keep an original error object in `error`
+ - add event handler for taking care lderror in `error` and `unhandledrejection` events
 
 
 ## v2.2.0

README.md

@@ -24,11 +24,12 @@ or
 
 ## Members
 
- - `id` - lderror deined error code.
- - `message` - custom error message (optional)
- - `stack` - stacktrace (optional)
- - `code` - http status code, if applicable (optional)
- - `log` - should this error be logged. default false. 
+ - `id`: lderror deined error code.
+ - `message`: custom error message (optional)
+ - `stack`: stacktrace (optional)
+ - `code`: http status code, if applicable (optional)
+ - `log`: should this error be logged. default false.
+ - `error`: an Error object constructed
 
 
 ## Helper Functions
@@ -57,6 +58,11 @@ lderror exports several help functions for making use lderror easier:
        - options:
          - `o`: user-defined object returned by `rule(id)`.
          - `e`: the original error object.
+ - `lderror.eventHandler`: helper event handler. See below section for more information.
+   - `eventHandler` provides two member functions:
+     - `error(evt)`: handler for `error` event.
+     - `rejection(evt)`: handler for `unhandledrejection` event.
+   - for both functions, return true if `lderror` is handled. otherwise false.
 
 
 ### Error Handler
@@ -95,11 +101,27 @@ Work along with `@plotdb/block` + `ldcvmgr`:
       .catch handler
 
 
+## error / unhandledrejection events
+
+You can use `lderror.eventHandler.error` and `lderror.eventHandler.rejection` to take care of lderror related errors:
+
+    window.addEventListenen("error", lderror.eventHandler.error);
+    window.addEventListenen("unhandledrejection", lderror.eventHandler.rejection);
+
+These handlers simply check if incoming error is a lderror with original error object; if it is, additional information is logged and the original error object will be thrown for showing stacktrace information.
+
+To wrap them along with your own event handler, test its return value and proceed if it returns `false`:
+
+    window.addEventListenen("error", function(evt) {
+      if(!lderror.eventHandler.error) { /* your own handler */ }
+    });
+
+
 ## Customized information
 
 Additional information can be added if needed:
 
- - redirect - instruct a redirect url in order to proper take care of this error. 
+ - redirect - instruct a redirect url in order to proper take care of this error.
 
 
 ## License

dist/index.js

@@ -35,7 +35,7 @@
     1028: "resource unavailable"
   };
   lderror = function(opt, id){
-    var _id, that;
+    var _id, that, e;
     opt == null && (opt = "");
     id == null && (id = 0);
     if (!(this instanceof lderror)) {
@@ -64,8 +64,9 @@
             : idmap[0] + " (id: " + (this.id || 0) + ")";
       }
     }
-    this.stack = new Error().stack;
     this.name = lderror.prototype.name;
+    this.stack = (e = import$(new Error(), this)).stack;
+    this.error = e;
     return this;
   };
   lderror.prototype = import$(Object.create(Error.prototype), {
@@ -140,6 +141,30 @@
     };
     return h;
   };
+  lderror.eventHandler = {
+    error: function(e){
+      if (e.error && e.error.name === 'lderror' && e.error.error && e.error !== e.error.error) {
+        console.warn("uncaught lderror", e.error);
+        console.warn("with its internal Error object thrown:");
+        e.preventDefault();
+        setTimeout(function(){
+          throw e.error.error;
+        }, 0);
+        return true;
+      }
+      return false;
+    },
+    rejection: function(e){
+      if (e.reason && e.reason.name === 'lderror' && e.reason.error) {
+        console.warn("Unhandled rejection with lderror:", e.reason);
+        console.warn("with its internal Error object thrown:");
+        throw e.reason.error;
+        e.preventDefault();
+        return true;
+      }
+      return false;
+    }
+  };
   if (typeof module != 'undefined' && module !== null) {
     module.exports = lderror;
   } else if (typeof window != 'undefined' && window !== null) {

dist/index.min.js

@@ -49,9 +49,12 @@ lderror = (opt="", id = 0) ->
       @message = if idmap[@id or 0] => that
       else if @id >= 100 and @id < 600 => "http code: #{@id}"
       else "#{idmap.0} (id: #{@id or 0})"
-  @stack = (new Error!).stack
   # otherwise stringify wont keep the name
   @name = lderror.prototype.name
+  @stack = (e = (new Error!) <<< @).stack
+  # this is especially useful to handle unhandledrejection.
+  # simply throw it again gives us the full stack to trace in dev console
+  @error = e
   @
 
 lderror.prototype = Object.create(Error.prototype) <<< do
@@ -88,5 +91,25 @@ lderror.handler = (o={}) ->
   h.is-on = ~> !![v for k,v of @s].filter((v)->v).length
   h
 
+lderror.event-handler =
+  error: (e) ->
+    if e.error and e.error.name == \lderror and e.error.error and e.error != e.error.error =>
+      console.warn "uncaught lderror", e.error
+      console.warn "with its internal Error object thrown:"
+      e.preventDefault!
+      # add a setTimeout so it will be handled again by this handler
+      setTimeout (->throw e.error.error), 0
+      return true
+    return false
+
+  rejection: (e) ->
+    if e.reason and e.reason.name == \lderror and e.reason.error =>
+      console.warn "Unhandled rejection with lderror:", e.reason
+      console.warn "with its internal Error object thrown:"
+      throw e.reason.error
+      e.preventDefault!
+      return true
+    return false
+
 if module? => module.exports = lderror
 else if window? => window.lderror = lderror