Hello, That'd be useful if there was a context that would be shared by every instances of a subflow. It's like having private static variables in a class. Every instances of the class have access to theses static variables. I can see many uses of this. For exemple: I want get config from a databa…

I totally agree with @adesjardins . A subflow is by essence a flow made to be reusable in another flow. It makes sense that the subflow can access the flow context of the flow using it, thus minimizing integration efforts between a flow and its subflow. Currently the only way I found to share infor…

[image] martin1: A subflow is by essence a flow made to be reusable in another flow. It makes sense that the subflow can access the flow context of the flow using it, thus minimizing integration efforts between a flow and its subflow. What if I have two flow tabs A and B and they each use a f…

OK, I admit a little misconception on my part on the scope of flows in node-red. :slight_smile: However, I can totally see something like that happening in a function node in a subflow: var namespace = get_flow_namespace(); // returns string eg: 'ns1-myflow' var contextData = flow.get(namespace);…

So why don't you - just before calling the sub flow - retreive the flow.variable and add it to msg.payload that will be sent to the sub flow?

Yes, it is a solution. I just like it less because I am trying to work in a more functional programming paradigm and I like to consider my msg object immutable. This is because my messages pass through many complex flows and I cannot keep track of the message state easily. So, yes, for now I will …

[image] martin1: I am trying to work in a more functional programming paradigm and I like to consider my msg object immutable Trying to operate this way in a node-red flow is probably self-defeating -- the msg object is expected to have its contents changed as it flows through each node... an…

It is also a bit of an anti-pattern to store per-message data in context. As soon as you have two messages being handled by your flow at the same time you then have to make sure one message's use of context doesn't conflict with the other.

I think I was not clear at first. I don't ask for a flow and a subflow to share the flow context. I don't ask for a subflow to share his flow context with other subflows. It would be a new context called... static_subflow. It's like static variables of a class X. If you instaciate multiple time …

Hi @adesjardins - my apologies for not responding to your original request. Yes, the concept of a subflow have its own context is one we're aware of and we will address it at some point. What we cannot practically do is introduce another context object in addition to flow and global - as nodes woul…

Shared subflow context

Core Development Feature Requests

adesjardins 8 November 2018 15:22 11

Nice,

I understand the difficulty of this. I think that sub-context shloud do it.

Thanks

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Shared subflow context

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