socketcluster | Highly scalable realtime pub/sub and RPC framework | Websocket library

PubSub is designed to decouple the subscribers and the publisher. So, your request is an anti-pattern of PubSub.

Anyway, if you publish a message into PubSub and there isn't subscription (I said "subsciprions" not "subscriber"), the message is dropped. Your publishers can still check if a subscription exists on a topic before processing the messages. Subscribers check isn't possible.

If there is one (or many) subscription, the message is send to it (if several subscription, the message is duplicated). The message are kept up to 7 days in the subscription, but you can reduce this duration according with your use case. by the way, when a subscriber will listen the subscription, it will be able to only receives and processes the relevant message, not the too old ones.

this context, almost certainly. I'm not entirely certain what this context will a function called inside socket.on get, but arrow functions use the lexical this, so that would be one solution.

In the end after trying many ways, you will try to solve this problem as follows:

Had the same error when used with react-test-renderer :

TypeError: Cannot read property 'default' of undefined

To fix it, I mocked native-base's Icon component in my jest's setup file:

It's a feature. For every Service in the same namespace, you get OTHERSVC_SERVICE_HOST and OTHERSVC_SERVICE_PORT environment variables, plus some others that come from the legacy Docker links feature. I don't know of any way to turn these off.

Actually using these is problematic in practice, because it depends on the consuming pod starting after the producing service is up, which is hard to guarantee; DNS lookups othersvc.default.svc.cluster.local may not resolve at runtime but won't have a missing environment variable. Conversely, if you might configure your pod with an environment variable named something like MICRO_SERVICE_HOST or DATABASE_PORT, those names are liable to be "stepped on" by the generated environment variables.

The way to resolve the issue is to add this to the iOS project file.

The error was emerging from the react-native-firebase package.

Updating the react-native-firebase package to the latest version resolved my problem.

Nevermind, have it figured out. Posting solution in case someone else needs a quick hint:

in scserver.js where it says options = { ... } add this: