I built a website sort of like an online directory for restaurants in my home town, and I am letting the users to leave their reviews about a specific restaurant, and what I need is to give access to the manager or owner of a specific restaurant to reply those reviews or to leave a comment on his node "restaurant", and he cannot reply or comments other restaurants except his. is their any way to achieve that?
IMO the Message module would be a possible solution to answer this question. Using this module, you can create your own custom "Reviews", which can be used to store (save) the data about them in relevant (custom) fields such as dates, contact info, scores and what not).
About Message types: think of them as equivalent to Content types, whereas you create messages (instead of nodes) of a specific Message type (instead of Content type).
Example included in Commerce Kickstart
A great sample of this can be found in Commerce Kickstart, which uses the Commerce Message module, to create "Events logging". In that case in the format of an Order History, as shown in this screenprint (from this module's project page).
More info about the Message module
The Message module is an amazing module, it is fully entity based, which implies that it perfectly (out of the box) integrates with modules such as Views, etc. And there is also quite a few questions about it on drupal.SE, many of them tagged with message-stack.
Though there is not a lot of documentation about it (which is what makes it a hidden gem ...). A possible way to get started with it, and to get an idea of the kind of things it can be used for, is to have a look at the answers to:
- How to create a basic message - notifications system displaying a real time message counter badge?
- How to show message view containing own and following activity?
- How to integrate messaging into a custom module?
- Is there a simple way to notify users about new posts on the site?