n8n-nodes-ephemeral-context

A powerful, in-memory "RAM" for n8n workflows. Teleport data between branches, manage counters, and build complex state entirely in memory.

Stop fighting with complex Merge Nodes just to pass data between disconnected branches. This node allows you to store, retrieve, and accumulate data instantly across any part of a workflow execution, or even share data across different workflows.

🚀 Key Features

• Teleport Data: Set variables in Branch A, read them in Branch B.
• Global High-Speed Cache: Share data between separate workflow executions (e.g., API rate limit counters).
• Advanced State Management: Atomic counters, Queues (Push/Pop/Shift), and Existence checks.
• Safety First: Memory limits to prevent crashes and automatic garbage collection.

📦 Operations

1. Set Value

Store values in memory.

• Modes:
  • Always Set: Overwrite or create.
  • If Not Exists (NX): Only set if the key is missing (locks).
  • If Exists (XX): Update only if it already exists.
• Key: Supports dot-notation (e.g., user.details.id).
• Value: String, Number, Boolean, Array, or Object.

2. Get / Check / Clear

• Get Value: Retrieve a specific value by key.
• Get All: Retrieve the entire store for the current scope.
• Check Exists: Efficiently check true/false if a key exists.
• Clear: Remove a specific key or reset the entire scope.

3. Atomic Counters

Thread-safe numeric operations.

• Increment / Decrement: Modify a number without race conditions. Perfect for counting loops or rate limiting.

4. Array Operations

Turn arrays into Queues or Stacks.

• Push: Append to end.
• Unshift: Prepend to start.
• Pop: Remove and return the last item (Stack LIFO).
• Shift: Remove and return the first item (Queue FIFO).
• Remove Item: Remove a key entirely.

🌐 Scopes

Control how long your data lives:

| Scope | Lifetime | Visibility | Use Case | | :--- | :--- | :--- | :--- | | Execution (Default) | Single Run | Isolated to current run | Passing variables between IF branches | | Workflow | App Lifecycle | Shared by all runs of ONE workflow | Aggregating data across multiple webhook calls | | Global | App Lifecycle | Shared by ALL workflows | Global rate limiters, cross-workflow signals |

Note: All data is stored in Memory (RAM). If you restart your n8n instance, all data is lost.

💡 Usage Scenarios

Scenario A: The "Disconnected Branch"

You have an IF node and want to collect data from both branches without complex merges.

• True Branch: Push ID to processed_ids.
• False Branch: Push ID to failed_ids.
• Finally: Get All to see the full report.

Scenario B: Global Rate Limiter

Prevent a specific API from being called too often across multiple workflows.

1. Scope: Global
2. Operation: Increment key api_usage_minute.
3. Checks if api_usage_minute > 100 before making the request.

Scenario C: "Once Processed" Lock

Ensure a resource is only processed once, even if triggered simultaneously.

1. Operation: Set with mode If Not Exists (NX).
2. Key: lock_resource_123.
3. If result success: false, stop execution.

⚠️ Limitations & Safety

1. Ephemeral: Data is lost on n8n restart.
2. Memory Limits:
   • Maximum 10MB per value.
   • Maximum 100MB total store size (soft limit).
3. Cluster Environments:
   • This node uses Process RAM.
   • If you use Queue Mode with multiple workers, "Global" and "Workflow" scopes WILL NOT sync between servers.
   • Execution scope works fine as long as the execution stays on one worker (avoid Wait nodes if using Queue Mode).

📥 Installation

npm install @ksoftm/n8n-nodes-ephemeral-context

License

MIT