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Is it safe to run multiple isolated instances of NodeBB and use LB to distribute load?

Moved Developer FAQ
  • stevefan1999-personalS

    I use a k8s deployment and scale it up according to my need to run the cluster instead of using the official guide of using built-in worker cluster forking mode, so I think that maybe there will be some problem if I run that with k8s, and I think the most notable potential problem would be the websocket requirement? Because it is a stateful protocol, there can be some disassociation problem of message ordering/context difference.

    I also see that I can add a Redis pubsub, and would that help solving this problem?

    julianJ 1 Reply
    0
  • julianJ

    @stevefan1999-personal Considerations when scaling NodeBB are detailed here: https://docs.nodebb.org/configuring/scaling/

    ... but possibly not in the most digestable way. In summary, here's what you need:

    • Redis configured in config.json so it will be used as pubsub and for storing user sessions (volatile data)
    • One of the workers needs isPrimary set to true in config.json, conversely, the other instances need jobsDisabled set to false
    • For socket.io, you will need to make sure to use a ip hashing strategy when routing requests from the load balancer. A typical round-robin style means the socket.io handshake will fail since it ends up hitting different servers.
    2

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    How do I retrieve the latest translations from Transifex without waiting for Misty?

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    julianJ

    Once a day, Misty pulls the latest translations in from Transifex. If you are a translator, and you wish to see your translations in NodeBB sooner rather than later, you can do so by running the pull command via the Transifex command line client.

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    How do I add custom user fields to my theme?

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    julianJ

    If you have a custom theme that introduces custom user fields into the edit page, you might have noticed that the fields don't seem to show up on the frontend even if they're saved in the database.
    Likewise, if you have some custom data you want to maintain on a per-user basis, and you tried using user.updateProfile, you might've noticed that your fields don't seem to save.

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    If you've saved a custom field into the user hash and you wish to retrieve it via User.getUsersFields(), you will have to explicitly whitelist it by attaching a hook listener to filter:user.whitelistFields. That plugin hook sends in { uids, whitelist }, where uids is an array of uids (requested by the calling script), and whitelist, which is an array containing user field properties.

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    Setting user data is comparatively simpler. We recommend using the user.updateProfile() method, as that has some sanity checks and special handling for certain fields. To allow the saving of a certain field, you will need to pass it in to the third argument of user.updateProfile():

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    How to add main post content of topic to topic lists?

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    nullpointerN

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  • julianJ

    How do I log into NodeBB from a separate app/SSO?

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    julianJ

    This topic was created as an entry in the Developer FAQ. Respond below if you have additional information to add re: SSO or other session-sharing implementations.

    The recommended method of sharing sessions between two separate and distinct applications is through OAuth2. We recommend this approach because NodeBB maintains its own user records, so that we can keep track of user-related metrics and other data. Relying on another database would be tricky, prone to breaking, and quite possibly dangerous.

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    Once that is set up, you'll want to take a look at the SSO plugin skeleton for customised OAuth deployments -- nodebb-plugin-sso-oauth. You'll take this plugin, fork it, and modify it to communicate with your OAuth endpoint.

    Once everything is working properly, you should be able to register and log in/out via your web app.

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