refactor: validate cloudevent version agnostic (#311)

Signed-off-by: Grant Timmerman <timmerman+devrel@google.com>

src/event/cloudevent.ts

@@ -8,7 +8,7 @@ import {
   CloudEventV1Attributes,
   CloudEventV1OptionalAttributes,
 } from "./interfaces";
-import { validateV1, validateV03 } from "./spec";
+import { validateCloudEvent } from "./spec";
 import { ValidationError, isBinary, asBase64, isValidType } from "./validation";
 import CONSTANTS from "../constants";
 import { isString } from "util";
@@ -174,12 +174,7 @@ export class CloudEvent implements CloudEventV1, CloudEventV03 {
    */
   public validate(): boolean {
     try {
-      if (this.specversion === Version.V1) {
-        return validateV1(this);
-      } else if (this.specversion === Version.V03) {
-        return validateV03(this);
-      }
-      throw new ValidationError("invalid payload");
+      return validateCloudEvent(this);
     } catch (e) {
       if (e instanceof ValidationError) {
         throw e;

src/event/spec.ts

@@ -3,25 +3,27 @@ import { ValidationError, isBase64 } from "./validation";
 
 import { CloudEventV1, CloudEventV03 } from "./interfaces";
 import { schemaV03, schemaV1 } from "./schemas";
+import { Version } from "./cloudevent";
 import CONSTANTS from "../constants";
 
 const ajv = new Ajv({ extendRefs: true });
 const isValidAgainstSchemaV1 = ajv.compile(schemaV1);
 const isValidAgainstSchemaV03 = ajv.compile(schemaV03);
 
-export function validateV1(event: CloudEventV1): boolean {
+export function validateCloudEvent(event: CloudEventV03 | CloudEventV1): boolean {
+  if (event.specversion === Version.V1) {
     if (!isValidAgainstSchemaV1(event)) {
       throw new ValidationError("invalid payload", isValidAgainstSchemaV1.errors);
     }
     return true;
-}
-
-export function validateV03(event: CloudEventV03): boolean {
+  } else if (event.specversion === Version.V03) {
     if (!isValidAgainstSchemaV03(event)) {
       throw new ValidationError("invalid payload", isValidAgainstSchemaV03.errors);
     }
     return checkDataContentEncoding(event);
   }
+  return false;
+}
 
 function checkDataContentEncoding(event: CloudEventV03): boolean {
   if (event.datacontentencoding) {

src/transport/http/binary_receiver.ts

@@ -1,6 +1,6 @@
 import { CloudEvent, Version } from "../..";
 import { CloudEventV1, CloudEventV03 } from "../../event/interfaces";
-import { validateV1, validateV03 } from "../../event/spec";
+import { validateCloudEvent } from "../../event/spec";
 import { Headers, validate } from "./headers";
 import { v03binaryParsers, v1binaryParsers } from "./versions";
 import { parserByContentType, MappedParser } from "../../parsers";
@@ -88,7 +88,7 @@ export class BinaryHTTPReceiver {
     }
 
     const cloudevent = new CloudEvent({ ...eventObj, data: parsedPayload } as CloudEventV1 | CloudEventV03);
-    this.version === Version.V1 ? validateV1(cloudevent) : validateV03(cloudevent);
+    validateCloudEvent(cloudevent);
     return cloudevent;
   }
 }

src/transport/http/structured_receiver.ts

@@ -5,7 +5,7 @@ import { parserByContentType } from "../../parsers";
 import { v1structuredParsers, v03structuredParsers } from "./versions";
 import { isString, isBase64, ValidationError, isStringOrObjectOrThrow } from "../../event/validation";
 import { CloudEventV1, CloudEventV03 } from "../../event/interfaces";
-import { validateV1, validateV03 } from "../../event/spec";
+import { validateCloudEvent } from "../../event/spec";
 import CONSTANTS from "../../constants";
 
 /**
@@ -85,7 +85,7 @@ export class StructuredHTTPReceiver {
     const cloudevent = new CloudEvent(eventObj as CloudEventV1 | CloudEventV03);
 
     // Validates the event
-    this.version === Version.V1 ? validateV1(cloudevent) : validateV03(cloudevent);
+    validateCloudEvent(cloudevent);
     return cloudevent;
   }
 }