JSON serializer
Serialize an HL7v2 AST into a compact, structured JSON document.
Serialize an HL7v2 AST into a compact, structured JSON document.
What it does
@glion/jsonify takes an HL7v2 AST — typically produced by @glion/parser — and emits a JSON representation that strips unist metadata (position, raw, type discriminators) and keeps only the meaningful HL7v2 shape: segment names, field indexes, values, and children. The result is a clean payload for downstream APIs, message queues, and analytics stores that want structured HL7v2 without the parser's internal tree representation.
Install
npm install @glion/jsonifyUse
import { hl7v2Parser } from "@glion/parser";
import { hl7v2Jsonify } from "@glion/jsonify";
import { unified } from "unified";
const msg = `MSH|^~\\&|HIS|RIH|EKG|EKG|200202150930||ADT^A01|MSG00001|P|2.4\rPID|||555-44-4444||DOE^JOHN`;
const file = await unified().use(hl7v2Parser).use(hl7v2Jsonify).process(msg);
console.log(String(file));Yields:
{
"type": "Message",
"children": [
{
"type": "Segment",
"name": "MSH",
"children": [
{ "type": "Field", "name": "MSH-1", "value": "|" },
{ "type": "Field", "name": "MSH-2", "value": "^~\\&" }
]
},
{
"type": "Segment",
"name": "PID",
"children": [
{ "type": "Field", "name": "PID-3", "value": "555-44-4444" },
{ "type": "Field", "name": "PID-5", "value": "DOE^JOHN" }
]
}
]
}API
unified().use(hl7v2Jsonify)
Register the plugin as the compiler of a unified processor. The processor's process() call returns a file whose stringified contents is the JSON document. No options.
JSON shape
Every node in the output has the following shape:
interface HL7v2JsonNode {
type: string; // "Message", "Segment", "Field", "Component", ...
name?: string; // segment name (e.g. "MSH") or field id (e.g. "PID-3")
index?: number; // positional index where relevant
value?: string; // leaf value for Field / Component / Subcomponent
delimiter?: string; // delimiter character when it is meaningful to preserve
children?: HL7v2JsonNode[]; // recursive shape for composite nodes
}Only the fields relevant to a given node appear in the output — Field nodes carry name and value, composite nodes carry name and children, and so on.