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Version: v0.1.15

Validate many resources against one schema registry

A validateResource call given schemas merges them with the built-in schemas into a new registry on every call. To validate many resources against the same schemas, build the registry once with buildRegistry and pass it as registry. Every call then reads that one registry, and its findings are the same as with schemas.

Build the registry once​

Build it where the schemas are made, and keep it for as long as the schemas do not change. Here the schema is a made-up resource type with one required element:

import { buildRegistry, parseResource, validateResource } from "@cosyte/fhir";

const registry = buildRegistry([
  { type: "Widget", elements: { status: { min: 1, max: 1, types: ["code"] } } },
]);

const widgets = ['{"resourceType":"Widget","status":"on"}', '{"resourceType":"Widget"}'];
const results = widgets.map((text) =>
  validateResource(parseResource(text).resource, { mode: "lenient", registry }),
);
results.map((result) => result.valid); // => [true, false]
results[1]?.issues.map((issue) => issue.code); // => ["CARDINALITY_MIN"]

Pass the registry, not the schemas​

When a call passes both registry and schemas, the registry is used and schemas is not read. Pass one or the other, so that a reader of the call sees which schemas it validates against.

Change a built-in schema​

The built-in schemas a registry returns are frozen and shared by every registry. To change one, copy it and its elements with a spread, change the copy, and register the copy with buildRegistry:

import { buildRegistry, parseResource, validateResource } from "@cosyte/fhir";

const builtIn = buildRegistry()("Patient");
const registry = buildRegistry([
  {
    type: "Patient",
    elements: {
      ...builtIn?.elements,
      birthDate: { min: 1, max: 1, types: ["date"] },
    },
  },
]);

const { resource } = parseResource('{"resourceType":"Patient","id":"syn-0001"}');
validateResource(resource, { registry }).issues.map((issue) => issue.code); // => ["CARDINALITY_MIN"]
validateResource(resource).valid; // => true

What it saves​

It saves the merge on every call, and a little peak heap. What a call allocates is about the same either way. The benchmark suite reads the two side by side on the vital-signs Observation, as validateResource with caller schemas each call and validateResource with a registry built once; Performance gives the latest readings.

Reference​