Fix issue #574 for a module without IOCs output (#620)

* Fix issue #574 for a module without IOCs output

src/mvt/common/cmd_check_iocs.py

@@ -65,6 +65,10 @@ class CmdCheckIOCS(Command):
                 m = iocs_module.from_json(
                     file_path, log=logging.getLogger(iocs_module.__module__)
                 )
+                if not m:
+                    log.warning("No result from this module, skipping it")
+                    continue
+
                 if self.iocs.total_ioc_count > 0:
                     m.indicators = self.iocs
                     m.indicators.log = m.log

src/mvt/common/module.py

@@ -69,10 +69,14 @@ class MVTModule:
     @classmethod
     def from_json(cls, json_path: str, log: logging.Logger):
         with open(json_path, "r", encoding="utf-8") as handle:
-            results = json.load(handle)
-            if log:
-                log.info('Loaded %d results from "%s"', len(results), json_path)
-            return cls(results=results, log=log)
+            try:
+                results = json.load(handle)
+                if log:
+                    log.info('Loaded %d results from "%s"', len(results), json_path)
+                return cls(results=results, log=log)
+            except json.decoder.JSONDecodeError as err:
+                log.error('Error to decode the json "%s" file: "%s"', json_path, err)
+                return None
 
     @classmethod
     def get_slug(cls) -> str: