Two-Path Optional Field Normalizer with Per-Field Provenance

How it works

1. 1.Manual Trigger starts the run with one empty item
2. 2.Code node emits five heterogeneous sample records with _idx
3. 3.If node checks discount_rate is defined, not null and not empty string
4. 4.Present path: Set with includeOtherFields adds _discount_path=present and discount_rate_text
5. 5.Absent path: NoOp passes the record through safely
6. 6.Merge in append mode with two inputs rejoins both branches
7. 7.Final Code node applies defaults, builds field_status, trims/uppercases and sorts by index

Use cases

• Unifying customer records coming from different JSON sources
• Preparing data before loading into systems that require a fixed schema
• Data quality auditing to see which fields were defaulted
• Avoiding silent failures downstream when optional fields are missing

Requirements

• n8n 2.45.7 or newer
• No credentials or external calls required
• Replace the sample node with your real source using the same keys
• Add _idx if you need original ordering preserved

Setup and testing in n8n

1. Import the template JSON into n8n
2. Click Execute Workflow and open Apply Defaults And Field Status
3. Verify five records ordered from index 0 to 4
4. Verify C-1004 shows invalid_default_applied while C-1002 and C-1005 show missing_default_applied
5. Edge case: empty the records array in the sample node and confirm status=empty_input
6. Edge case: add a record with discount_rate '0.2' and confirm it stays 0.2 with status original

Service Value

Ready-made workflow template for automation delivery and service execution.