Subscription thread safety

[gitmodimo]

It seems subscribe/unsubscribe/deliver is not thread safe.
These fields in Request class are not protected:

	internal::sorted_map<SubscriptionKey, std::shared_ptr<SubscriptionData>> _subscriptions;
	internal::sorted_map<SubscriptionName, internal::sorted_set<SubscriptionKey>> _listeners;

[Coder666]

We had the same issue and just put a thread safe wrapper around the desired functionality.

Note also that running multiple concurrent queries on the service::Request/Operations object is not thread safe either, we simply allocate one per thread/query as required.

[wravery]

We had the same issue and just put a thread safe wrapper around the desired functionality.

This sounds like a good workaround, but I will look into protecting the subscription members.

Note also that running multiple concurrent queries on the service::Request/Operations object is not thread safe either, we simply allocate one per thread/query as required.

@Coder666, do you mean because of the state in the ValidateExecutableVisitor in the _validation member? That could be protected too.

[Coder666]

Is there any chance of getting this back ported into 3.X.X ?

[wravery]

Yes, that's what #205 did. 👍🏼

[Coder666]

Cheers