Register cached errors (#587)

* register fetch errors in `cachedMeta.js`

* bugfix warning

Author: nleush

lib/core.js

@@ -1459,9 +1459,9 @@
 
                 var fetch_data = {...data};
 
-                if (!data.error) {
+                if (!data.error && !data.status_code) {
                     console.warn('No error param in registerFetchError data');
-                } else {
+                } else if (data.error) {
                     // Convert runtime `error` to `error_code` and `error_message`.
                     if (typeof data.error === 'string') {
                         fetch_data.error_code = data.error

lib/plugins/system/meta/cachedMeta.js

@@ -73,11 +73,6 @@ export default {
                         return noCacheFound();
                     }
 
-                    options.registerFetch({
-                        source: 'cache',
-                        url: url
-                    });
-
                     if (data.error) {
 
                         if (data.error.redirect) {
@@ -88,13 +83,36 @@ export default {
                             }
                         }
 
+                        if (data.error.responseStatusCode !== 200) {
+                            options.registerFetchError({
+                                source: 'cache',
+                                url: url,
+                                status_code: data.error.responseStatusCode
+                            });
+                        }
+
                         // If data object has error attribute - return as error (e.g. redirect).
                         log('   -- Using cached htmlparser error for: ' + url);
                         cb(data.error);
                     } else if (data.htmlparser) {
+
+                        if (data.htmlparser.__statusCode !== 200) {
+                            options.registerFetchError({
+                                source: 'cache',
+                                url: url,
+                                status_code: data.htmlparser.__statusCode
+                            });
+                        }
+
                         log('   -- Using cached htmlparser data for: ' + url);
                         cb(null, data.htmlparser);
                     } else {
+
+                        options.registerFetch({
+                            source: 'cache',
+                            url: url
+                        });
+                        
                         log('   -- Using cached meta for: ' + url);
                         cb(null, {
                             meta: data,