thenAllPlugin

Global then plugin, executed whenever a child node is created in the stream chain, used for global monitoring and handling of node creation.

Type Definition

thenAllPlugin: (unsubscribe: () => void, observable: Observable<T>) => void

Parameters

• unsubscribe: Unsubscribe function, can be used to unsubscribe the current observer node
• observable: The newly created observer node instance

Return Value

No return value (void)

Core Behavior

• Global execution: Executes whenever a child node is created via then, catch, or finally in the stream chain
• Node creation timing: Executes immediately after a new observer node is created
• Root node only: Can only be used on the root Stream node; child nodes cannot use thenAll plugins
• Propagates to all child nodes: thenAll plugins on the root node affect the creation of all child nodes in the chain

Execution Mechanism

From the source code, the execution logic of thenAll plugins is as follows:

#runThenPlugin(observer: Observable) {
  const thenPlugins = this._root
    ? this._root.#plugin.thenAll.concat(this.#plugin.then)
    : this.#plugin.then
  thenPlugins.forEach((fn) => {
    safeCallback(fn)(() => observer.#unsubscribeObservable(), observer)
  })
}

• Merges the thenAll plugins of the root node and the then plugins of the current node
• Executes each plugin in order, passing in the unsubscribe function and the newly created observer node

Notes

1. Root node only: thenAll plugins can only be used on the root Stream node; using on child nodes will throw an error
2. Does not modify data flow: thenAll plugins do not affect data propagation or processing
3. Execution timing: Executes immediately after each new node is created, not during data flow
4. Unsubscribe: Use the provided unsubscribe function to unsubscribe a specific node
5. Performance consideration: Avoid complex calculations in plugins, as they execute on every node creation

Relationship with Other Plugins

• vs then plugin: thenAll executes on all node creations, then plugin only on specific nodes
• vs executeAll: thenAll executes when nodes are created, executeAll executes when data flows
• vs execute: thenAll is global, execute is per node
• Applicable scenarios: thenAll is suitable for global monitoring, debugging, performance analysis, etc., that need to intervene during node creation