fix(parser): LambdaFunctionUrl envelope assumes JSON string in body (#3514)

Author: am29d

packages/parser/src/envelopes/lambda.ts

@@ -2,7 +2,7 @@ import type { ZodSchema, z } from 'zod';
 import { ParseError } from '../errors.js';
 import { LambdaFunctionUrlSchema } from '../schemas/index.js';
 import type { ParsedResult } from '../types/index.js';
-import { Envelope, envelopeDiscriminator } from './envelope.js';
+import { envelopeDiscriminator } from './envelope.js';
 
 /**
  * Lambda function URL envelope to extract data within body key
@@ -14,37 +14,38 @@ export const LambdaFunctionUrlEnvelope = {
    */
   [envelopeDiscriminator]: 'object' as const,
   parse<T extends ZodSchema>(data: unknown, schema: T): z.infer<T> {
-    const parsedEnvelope = LambdaFunctionUrlSchema.parse(data);
-
-    if (!parsedEnvelope.body) {
-      throw new Error('Body field of Lambda function URL event is undefined');
+    try {
+      return LambdaFunctionUrlSchema.extend({
+        body: schema,
+      }).parse(data).body;
+    } catch (error) {
+      throw new ParseError('Failed to parse Lambda function URL body', {
+        cause: error as Error,
+      });
     }
-
-    return Envelope.parse(parsedEnvelope.body, schema);
   },
 
-  safeParse<T extends ZodSchema>(data: unknown, schema: T): ParsedResult<unknown, z.infer<T>> {
-    const parsedEnvelope = LambdaFunctionUrlSchema.safeParse(data);
-
-    if (!parsedEnvelope.success) {
-      return {
-        success: false,
-        error: new ParseError('Failed to parse Lambda function URL envelope'),
-        originalEvent: data,
-      };
-    }
+  safeParse<T extends ZodSchema>(
+    data: unknown,
+    schema: T
+  ): ParsedResult<unknown, z.infer<T>> {
+    const results = LambdaFunctionUrlSchema.extend({
+      body: schema,
+    }).safeParse(data);
 
-    const parsedBody = Envelope.safeParse(parsedEnvelope.data.body, schema);
-    if (!parsedBody.success) {
+    if (!results.success) {
       return {
         success: false,
         error: new ParseError('Failed to parse Lambda function URL body', {
-          cause: parsedBody.error,
+          cause: results.error,
         }),
         originalEvent: data,
       };
     }
 
-    return parsedBody;
+    return {
+      success: true,
+      data: results.data.body,
+    };
   },
 };

packages/parser/tests/events/lambdaFunctionUrlEventPathTrailingSlash.json renamed to packages/parser/tests/events/lambda/base.json

@@ -1,7 +1,7 @@
 {
   "version": "2.0",
   "routeKey": "$default",
-  "rawPath": "/my/path/",
+  "rawPath": "/",
   "rawQueryString": "parameter1=value1&parameter1=value2&parameter2=value",
   "cookies": ["cookie1", "cookie2"],
   "headers": {
@@ -31,7 +31,7 @@
     "domainPrefix": "<url-id>",
     "http": {
       "method": "POST",
-      "path": "/my/path",
+      "path": "/",
       "protocol": "HTTP/1.1",
       "sourceIp": "123.123.123.123",
       "userAgent": "agent"
@@ -42,7 +42,7 @@
     "time": "12/Mar/2020:19:03:58 +0000",
     "timeEpoch": 1583348638390
   },
-  "body": "Hello from client!",
+  "body": null,
   "pathParameters": null,
   "isBase64Encoded": false,
   "stageVariables": null

packages/parser/tests/events/lambdaFunctionUrlEvent.json renamed to packages/parser/tests/events/lambda/get-request.json

@@ -0,0 +1,48 @@
+{
+  "version": "2.0",
+  "routeKey": "$default",
+  "rawQueryString": "parameter1=value1&parameter1=value2&parameter2=value",
+  "cookies": ["cookie1", "cookie2"],
+  "headers": {
+    "header1": "value1",
+    "header2": "value1,value2"
+  },
+  "queryStringParameters": {
+    "parameter1": "value1,value2",
+    "parameter2": "value"
+  },
+  "requestContext": {
+    "accountId": "123456789012",
+    "apiId": "<urlid>",
+    "authentication": null,
+    "authorizer": {
+      "iam": {
+        "accessKey": "AKIA...",
+        "accountId": "111122223333",
+        "callerId": "AIDA...",
+        "cognitoIdentity": null,
+        "principalOrgId": null,
+        "userArn": "arn:aws:iam::111122223333:user/example-user",
+        "userId": "AIDA..."
+      }
+    },
+    "domainName": "<url-id>.lambda-url.us-west-2.on.aws",
+    "domainPrefix": "<url-id>",
+    "http": {
+      "method": "POST",
+      "path": "/",
+      "protocol": "HTTP/1.1",
+      "sourceIp": "123.123.123.123",
+      "userAgent": "agent"
+    },
+    "requestId": "id",
+    "routeKey": "$default",
+    "stage": "$default",
+    "time": "12/Mar/2020:19:03:58 +0000",
+    "timeEpoch": 1583348638390
+  },
+  "body": null,
+  "pathParameters": null,
+  "isBase64Encoded": false,
+  "stageVariables": null
+}

packages/parser/tests/events/lambdaFunctionUrlIAMEvent.json renamed to packages/parser/tests/events/lambda/iam-auth.json

@@ -1,98 +1,139 @@
-import { generateMock } from '@anatine/zod-mock';
-import type {
-  APIGatewayProxyEventV2,
-  LambdaFunctionURLEvent,
-} from 'aws-lambda';
 import { describe, expect, it } from 'vitest';
-import { ZodError } from 'zod';
+import { ZodError, z } from 'zod';
 import { ParseError } from '../../../src';
 import { LambdaFunctionUrlEnvelope } from '../../../src/envelopes/index.js';
-import { TestEvents, TestSchema } from '../schema/utils.js';
+import { JSONStringified } from '../../../src/helpers';
+import type { LambdaFunctionUrlEvent } from '../../../src/types';
+import { getTestEvent, omit } from '../schema/utils.js';
 
-describe('Lambda Functions Url ', () => {
-  describe('parse', () => {
-    it('should parse custom schema in envelope', () => {
-      const testEvent =
-        TestEvents.lambdaFunctionUrlEvent as APIGatewayProxyEventV2;
-      const data = generateMock(TestSchema);
+describe('Envelope: Lambda function URL', () => {
+  const schema = z
+    .object({
+      message: z.string(),
+    })
+    .strict();
 
-      testEvent.body = JSON.stringify(data);
+  const baseEvent = getTestEvent<LambdaFunctionUrlEvent>({
+    eventsPath: 'lambda',
+    filename: 'base',
+  });
+
+  describe('Method: parse', () => {
+    it('throws if the payload does not match the schema', () => {
+      // Prepare
+      const event = structuredClone(baseEvent);
 
-      expect(LambdaFunctionUrlEnvelope.parse(testEvent, TestSchema)).toEqual(
-        data
+      // Act & Assess
+      expect(() => LambdaFunctionUrlEnvelope.parse(event, schema)).toThrow(
+        expect.objectContaining({
+          message: expect.stringContaining(
+            'Failed to parse Lambda function URL body'
+          ),
+          cause: expect.objectContaining({
+            issues: [
+              {
+                code: 'invalid_type',
+                expected: 'object',
+                received: 'null',
+                path: ['body'],
+                message: 'Expected object, received null',
+              },
+            ],
+          }),
+        })
       );
     });
 
-    it('should throw when no body provided', () => {
-      const testEvent =
-        TestEvents.lambdaFunctionUrlEvent as LambdaFunctionURLEvent;
-      testEvent.body = undefined;
+    it('parses a Lambda function URL event with plain text', () => {
+      // Prepare
+      const event = structuredClone(baseEvent);
+      event.body = 'hello world';
 
-      expect(() =>
-        LambdaFunctionUrlEnvelope.parse(testEvent, TestSchema)
-      ).toThrow();
+      // Act
+      const result = LambdaFunctionUrlEnvelope.parse(event, z.string());
+
+      // Assess
+      expect(result).toEqual('hello world');
     });
 
-    it('should throw when envelope is not valid', () => {
-      expect(() =>
-        LambdaFunctionUrlEnvelope.parse({ foo: 'bar' }, TestSchema)
-      ).toThrow();
+    it('parses a Lambda function URL event with JSON-stringified body', () => {
+      // Prepare
+      const event = structuredClone(baseEvent);
+      event.body = JSON.stringify({ message: 'hello world' });
+
+      // Act
+      const result = LambdaFunctionUrlEnvelope.parse(
+        event,
+        JSONStringified(schema)
+      );
+
+      // Assess
+      expect(result).toEqual({ message: 'hello world' });
     });
 
-    it('should throw when body does not match schema', () => {
-      const testEvent =
-        TestEvents.lambdaFunctionUrlEvent as APIGatewayProxyEventV2;
-      testEvent.body = JSON.stringify({ foo: 'bar' });
+    it('parses a Lambda function URL event with binary body', () => {
+      // Prepare
+      const event = structuredClone(baseEvent);
+      event.body = Buffer.from('hello world').toString('base64');
+      event.headers['content-type'] = 'application/octet-stream';
+      event.isBase64Encoded = true;
+
+      // Act
+      const result = LambdaFunctionUrlEnvelope.parse(event, z.string());
 
-      expect(() =>
-        LambdaFunctionUrlEnvelope.parse(testEvent, TestSchema)
-      ).toThrow();
+      // Assess
+      expect(result).toEqual('aGVsbG8gd29ybGQ=');
     });
   });
-  describe('safeParse', () => {
-    it('should parse custom schema in envelope', () => {
-      const testEvent =
-        TestEvents.lambdaFunctionUrlEvent as APIGatewayProxyEventV2;
-      const data = generateMock(TestSchema);
+  describe('Method: safeParse', () => {
+    it('parses Lambda function URL event', () => {
+      // Prepare
+      const event = structuredClone(baseEvent);
+      event.body = JSON.stringify({ message: 'hello world' });
 
-      testEvent.body = JSON.stringify(data);
+      // Act
+      const result = LambdaFunctionUrlEnvelope.safeParse(
+        event,
+        JSONStringified(schema)
+      );
 
-      expect(
-        LambdaFunctionUrlEnvelope.safeParse(testEvent, TestSchema)
-      ).toEqual({
+      // Assess
+      expect(result).toEqual({
         success: true,
-        data,
+        data: { message: 'hello world' },
       });
     });
 
-    it('should return original event when envelope is not valid', () => {
-      expect(
-        LambdaFunctionUrlEnvelope.safeParse({ foo: 'bar' }, TestSchema)
-      ).toEqual({
-        success: false,
-        error: expect.any(ParseError),
-        originalEvent: { foo: 'bar' },
-      });
-    });
+    it('returns an error when the event is not valid', () => {
+      // Prepare
+      const event = omit(['rawPath'], structuredClone(baseEvent));
 
-    it('should return original event when body does not match schema', () => {
-      const testEvent =
-        TestEvents.lambdaFunctionUrlEvent as APIGatewayProxyEventV2;
-      testEvent.body = JSON.stringify({ foo: 'bar' });
+      // Act
+      const result = LambdaFunctionUrlEnvelope.safeParse(event, schema);
 
-      const parseResult = LambdaFunctionUrlEnvelope.safeParse(
-        testEvent,
-        TestSchema
-      );
-      expect(parseResult).toEqual({
+      // Assess
+      expect(result).toEqual({
         success: false,
-        error: expect.any(ParseError),
-        originalEvent: testEvent,
+        error: new ParseError('Failed to parse Lambda function URL body', {
+          cause: new ZodError([
+            {
+              code: 'invalid_type',
+              expected: 'string',
+              received: 'undefined',
+              path: ['rawPath'],
+              message: 'Required',
+            },
+            {
+              code: 'invalid_type',
+              expected: 'object',
+              received: 'null',
+              path: ['body'],
+              message: 'Expected object, received null',
+            },
+          ]),
+        }),
+        originalEvent: event,
       });
-
-      if (!parseResult.success && parseResult.error) {
-        expect(parseResult.error.cause).toBeInstanceOf(ZodError);
-      }
     });
   });
 });

packages/parser/tests/events/lambda/invalid.json

@@ -1,19 +1,37 @@
 import { describe, expect, it } from 'vitest';
 import { LambdaFunctionUrlSchema } from '../../../src/schemas/';
-import { TestEvents } from './utils.js';
+import { getTestEvent } from './utils.js';
 
-describe('Lambda ', () => {
-  it('should parse lambda event', () => {
-    const lambdaFunctionUrlEvent = TestEvents.lambdaFunctionUrlEvent;
+describe('Schema: LambdaFunctionUrl', () => {
+  const eventsPath = 'lambda';
 
-    expect(LambdaFunctionUrlSchema.parse(lambdaFunctionUrlEvent)).toEqual(
-      lambdaFunctionUrlEvent
-    );
+  it('throw when the event is invalid', () => {
+    // Prepare
+    const event = getTestEvent({ eventsPath, filename: 'invalid' });
+
+    // Act & Assess
+    expect(() => LambdaFunctionUrlSchema.parse(event)).toThrow();
+  });
+
+  it('parses a valid event', () => {
+    // Prepare
+    const event = getTestEvent({ eventsPath, filename: 'get-request' });
+
+    // Act
+    const parsedEvent = LambdaFunctionUrlSchema.parse(event);
+
+    // Assess
+    expect(parsedEvent).toEqual(event);
   });
 
-  it('should parse url IAM event', () => {
-    const urlIAMEvent = TestEvents.lambdaFunctionUrlIAMEvent;
+  it('parses iam event', () => {
+    // Prepare
+    const event = getTestEvent({ eventsPath, filename: 'iam-auth' });
+
+    // Act
+    const parsedEvent = LambdaFunctionUrlSchema.parse(event);
 
-    expect(LambdaFunctionUrlSchema.parse(urlIAMEvent)).toEqual(urlIAMEvent);
+    //
+    expect(parsedEvent).toEqual(event);
   });
 });