feat(parser): make parse function available standalone (#4300)

Author: sdangol

packages/parser/src/index.ts

@@ -1,2 +1,3 @@
 export { ParseError } from './errors.js';
+export { parse } from './parser.js';
 export { parser } from './parserDecorator.js';

packages/parser/tests/unit/parser.test.ts

@@ -0,0 +1,136 @@
+import { describe, expect, it } from 'vitest';
+import { z } from 'zod';
+import { EventBridgeEnvelope } from '../../src/envelopes/eventbridge.js';
+import { SqsEnvelope } from '../../src/envelopes/sqs.js';
+import { ParseError } from '../../src/errors.js';
+import { parse } from '../../src/parser.js';
+import type { EventBridgeEvent, SqsEvent } from '../../src/types/index.js';
+import { getTestEvent } from './helpers/utils.js';
+
+describe('Parser', () => {
+  const schema = z
+    .object({
+      name: z.string(),
+      age: z.number(),
+    })
+    .strict();
+  const baseSqsEvent = getTestEvent<SqsEvent>({
+    eventsPath: 'sqs',
+    filename: 'base',
+  });
+  const baseEventBridgeEvent = getTestEvent<EventBridgeEvent>({
+    eventsPath: 'eventbridge',
+    filename: 'base',
+  });
+  const JSONPayload = { name: 'John', age: 18 };
+
+  it('parses an event with schema and envelope', async () => {
+    // Prepare
+    const event = structuredClone(baseSqsEvent);
+    event.Records[1].body = 'bar';
+
+    // Act
+
+    const result = parse(event, SqsEnvelope, z.string());
+
+    // Assess
+    expect(result).toStrictEqual(['Test message.', 'bar']);
+  });
+
+  it('throws when envelope does not match', async () => {
+    // Prepare
+    const event = structuredClone(baseEventBridgeEvent);
+
+    // Act & Assess
+    expect(() => parse(event, SqsEnvelope, z.string())).toThrow();
+  });
+
+  it('throws when schema does not match', async () => {
+    // Prepare
+    const event = structuredClone(baseSqsEvent);
+    // @ts-expect-error - setting an invalid body
+    event.Records[1].body = undefined;
+
+    // Act & Assess
+    expect(() => parse(event, SqsEnvelope, z.string())).toThrow();
+  });
+
+  it('parses the event successfully', async () => {
+    // Prepare
+    const event = 42;
+
+    // Act
+    const result = parse(event, undefined, z.number());
+
+    // Assess
+    expect(result).toEqual(event);
+  });
+
+  it('throws when the event does not match the schema', async () => {
+    // Prepare
+    const event = structuredClone(JSONPayload);
+
+    // Act & Assess
+    expect(() => parse(event, undefined, z.number())).toThrow();
+  });
+
+  it('returns the payload when using safeParse', async () => {
+    // Prepare
+    const event = structuredClone(JSONPayload);
+
+    // Act
+    const result = parse(event, undefined, schema, true);
+
+    // Assess
+    expect(result).toEqual({
+      success: true,
+      data: event,
+    });
+  });
+
+  it('returns the error when using safeParse and the payload is invalid', async () => {
+    // Prepare
+    const event = structuredClone(JSONPayload);
+
+    // Act
+    const result = parse(event, undefined, z.string(), true);
+
+    // Assess
+    expect(result).toEqual({
+      success: false,
+      error: expect.any(ParseError),
+      originalEvent: event,
+    });
+  });
+
+  it('returns the payload when using safeParse with envelope', async () => {
+    // Prepare
+    const detail = structuredClone(JSONPayload);
+    const event = structuredClone(baseEventBridgeEvent);
+    event.detail = detail;
+
+    // Act
+    const result = parse(event, EventBridgeEnvelope, schema, true);
+
+    // Assess
+    expect(result).toStrictEqual({
+      success: true,
+      data: detail,
+    });
+  });
+
+  it('returns an error when using safeParse with envelope and the payload is invalid', async () => {
+    // Prepare
+    const event = structuredClone(baseEventBridgeEvent);
+
+    // Act
+    const result = parse(event, EventBridgeEnvelope, z.string(), true);
+
+    // Assess
+    expect(result).toStrictEqual({
+      success: false,
+      error: expect.any(ParseError),
+      originalEvent: event,
+    });
+  });
+});