BREAKING CHANGE: use string instead of enum for Version (#561)

TypeScript does not consider enum values equivalent, even if the string
representation is the same. So, when a module imports `cloudevents` and
also has a dependency on `cloudevents` this can cause conflicts where
the `CloudEvent.version` attribute is not considered equal when, in
fact, it is.

Changing the `enum` to a string is pretty straightforward, but should be
considered a breaking change since TypeScript dependents will
potentially fail the build with a change like this.

Signed-off-by: Lance Ball <[email protected]>

src/event/cloudevent.ts

@@ -12,12 +12,10 @@ import { validateCloudEvent } from "./spec";
 import { ValidationError, isBinary, asBase64, isValidType, base64AsBinary } from "./validation";
 
 /**
- * An enum representing the CloudEvent specification version
+ * Constants representing the CloudEvent specification version
  */
-export const enum Version {
-  V1 = "1.0",
-  V03 = "0.3",
-}
+export const V1 = "1.0";
+export const V03 = "0.3";
 
 /**
  * A CloudEvent describes event data in common formats to provide
@@ -28,7 +26,7 @@ export class CloudEvent<T = undefined> implements CloudEventV1<T> {
   id: string;
   type: string;
   source: string;
-  specversion: Version;
+  specversion: string;
   datacontenttype?: string;
   dataschema?: string;
   subject?: string;
@@ -69,7 +67,7 @@ export class CloudEvent<T = undefined> implements CloudEventV1<T> {
     this.source = properties.source as string;
     delete (properties as any).source;
 
-    this.specversion = (properties.specversion as Version) || Version.V1;
+    this.specversion = (properties.specversion) || V1;
     delete properties.specversion;
 
     this.datacontenttype = properties.datacontenttype;
@@ -103,9 +101,9 @@ export class CloudEvent<T = undefined> implements CloudEventV1<T> {
     delete properties.data;
 
     // sanity checking
-    if (this.specversion === Version.V1 && this.schemaurl) {
+    if (this.specversion === V1 && this.schemaurl) {
       throw new TypeError("cannot set schemaurl on version 1.0 event");
-    } else if (this.specversion === Version.V03 && this.dataschema) {
+    } else if (this.specversion === V03 && this.dataschema) {
       throw new TypeError("cannot set dataschema on version 0.3 event");
     }
 

src/event/spec.ts

@@ -6,12 +6,12 @@
 import { ValidationError } from "./validation";
 
 import { CloudEventV1 } from "./interfaces";
-import { Version } from "./cloudevent";
+import { V1 } from "./cloudevent";
 import validate from "../schema/v1";
 
 
 export function validateCloudEvent<T>(event: CloudEventV1<T>): boolean {
-  if (event.specversion === Version.V1) {
+  if (event.specversion === V1) {
     if (!validate(event)) {
       throw new ValidationError("invalid payload", (validate as any).errors);
     }

src/index.ts

@@ -3,13 +3,13 @@
  SPDX-License-Identifier: Apache-2.0
 */
 
-import { CloudEvent, Version } from "./event/cloudevent";
+import { CloudEvent, V1, V03 } from "./event/cloudevent";
 import { ValidationError } from "./event/validation";
 import { CloudEventV1, CloudEventV1Attributes } from "./event/interfaces";
 
 import { Options, TransportFunction, EmitterFunction, emitterFor, Emitter } from "./transport/emitter";
 import { httpTransport } from "./transport/http";
-import { 
+import {
   Headers, Mode, Binding, HTTP, Kafka, KafkaEvent, KafkaMessage, Message, MQTT, MQTTMessage, MQTTMessageFactory,
   Serializer, Deserializer } from "./message";
 
@@ -18,7 +18,8 @@ import CONSTANTS from "./constants";
 export {
   // From event
   CloudEvent,
-  Version,
+  V1,
+  V03,
   ValidationError,
   Mode,
   HTTP,

src/message/http/headers.ts

@@ -6,7 +6,7 @@
 import { PassThroughParser, DateParser, MappedParser } from "../../parsers";
 import { CloudEventV1 } from "../..";
 import { Headers } from "../";
-import { Version } from "../../event/cloudevent";
+import { V1 } from "../../event/cloudevent";
 import CONSTANTS from "../../constants";
 
 export const allowedContentTypes = [CONSTANTS.DEFAULT_CONTENT_TYPE, CONSTANTS.MIME_JSON, CONSTANTS.MIME_OCTET_STREAM];
@@ -27,7 +27,7 @@ export const requiredHeaders = [
 export function headersFor<T>(event: CloudEventV1<T>): Headers {
   const headers: Headers = {};
   let headerMap: Readonly<{ [key: string]: MappedParser }>;
-  if (event.specversion === Version.V1) {
+  if (event.specversion === V1) {
     headerMap = v1headerMap;
   } else {
     headerMap = v03headerMap;

src/message/http/index.ts

@@ -5,7 +5,7 @@
 
 import { types } from "util";
 
-import { CloudEvent, CloudEventV1, CONSTANTS, Mode, Version } from "../..";
+import { CloudEvent, CloudEventV1, CONSTANTS, Mode, V1, V03 } from "../..";
 import { Message, Headers, Binding } from "..";
 
 import {
@@ -147,19 +147,19 @@ function getVersion(mode: Mode, headers: Headers, body: string | Record<string,
       return (body as Record<string, string>).specversion;
     }
   }
-  return Version.V1;
+  return V1;
 }
 
 /**
  * Parses an incoming HTTP Message, converting it to a {CloudEvent}
  * instance if it conforms to the Cloud Event specification for this receiver.
  *
  * @param {Message} message the incoming HTTP Message
- * @param {Version} version the spec version of the incoming event
+ * @param {string} version the spec version of the incoming event
  * @returns {CloudEvent} an instance of CloudEvent representing the incoming request
  * @throws {ValidationError} of the event does not conform to the spec
  */
-function parseBinary<T>(message: Message, version: Version): CloudEvent<T> {
+function parseBinary<T>(message: Message, version: string): CloudEvent<T> {
   const headers = { ...message.headers };
   let body = message.body;
 
@@ -169,7 +169,7 @@ function parseBinary<T>(message: Message, version: Version): CloudEvent<T> {
   const sanitizedHeaders = sanitize(headers);
 
   const eventObj: { [key: string]: unknown | string | Record<string, unknown> } = {};
-  const parserMap: Record<string, MappedParser> = version === Version.V03 ? v03binaryParsers : v1binaryParsers;
+  const parserMap: Record<string, MappedParser> = version === V03 ? v03binaryParsers : v1binaryParsers;
 
   for (const header in parserMap) {
     if (sanitizedHeaders[header]) {
@@ -206,11 +206,11 @@ function parseBinary<T>(message: Message, version: Version): CloudEvent<T> {
  * Creates a new CloudEvent instance based on the provided payload and headers.
  *
  * @param {Message} message the incoming Message
- * @param {Version} version the spec version of this message (v1 or v03)
+ * @param {string} version the spec version of this message (v1 or v03)
  * @returns {CloudEvent} a new CloudEvent instance for the provided headers and payload
  * @throws {ValidationError} if the payload and header combination do not conform to the spec
  */
-function parseStructured<T>(message: Message, version: Version): CloudEvent<T> {
+function parseStructured<T>(message: Message, version: string): CloudEvent<T> {
   const payload = message.body;
   const headers = message.headers;
 
@@ -227,7 +227,7 @@ function parseStructured<T>(message: Message, version: Version): CloudEvent<T> {
   const incoming = { ...(parser.parse(payload as string) as Record<string, unknown>) };
 
   const eventObj: { [key: string]: unknown } = {};
-  const parserMap: Record<string, MappedParser> = version === Version.V03 ? v03structuredParsers : v1structuredParsers;
+  const parserMap: Record<string, MappedParser> = version === V03 ? v03structuredParsers : v1structuredParsers;
 
   for (const key in parserMap) {
     const property = incoming[key];

test/integration/cloud_event_test.ts

@@ -7,7 +7,7 @@ import path from "path";
 import fs from "fs";
 
 import { expect } from "chai";
-import { CloudEvent, CloudEventV1, ValidationError, Version } from "../../src";
+import { CloudEvent, CloudEventV1, ValidationError, V1 } from "../../src";
 import { asBase64 } from "../../src/event/validation";
 
 const type = "org.cncf.cloudevents.example";
@@ -16,7 +16,7 @@ const id = "b46cf653-d48a-4b90-8dfa-355c01061361";
 
 const fixture = Object.freeze({
   id,
-  specversion: Version.V1,
+  specversion: V1,
   source,
   type,
   data: `"some data"`
@@ -165,7 +165,7 @@ describe("A 1.0 CloudEvent", () => {
   });
 
   it("can be constructed with an ID", () => {
-    const ce = new CloudEvent({ id: "1234", specversion: Version.V1, source, type });
+    const ce = new CloudEvent({ id: "1234", specversion: V1, source, type });
     expect(ce.id).to.equal("1234");
   });
 
@@ -280,7 +280,7 @@ describe("A 1.0 CloudEvent", () => {
     const obj = JSON.parse(json as string);
     expect(obj.type).to.equal(type);
     expect(obj.source).to.equal(source);
-    expect(obj.specversion).to.equal(Version.V1);
+    expect(obj.specversion).to.equal(V1);
   });
 
   it("throws if the provded source is empty string", () => {

test/integration/kafka_tests.ts

@@ -7,7 +7,7 @@ import path from "path";
 import fs from "fs";
 
 import { expect } from "chai";
-import { CloudEvent, CONSTANTS, Version } from "../../src";
+import { CloudEvent, CONSTANTS, V1 } from "../../src";
 import { asBase64 } from "../../src/event/validation";
 import { Message, Kafka, KafkaMessage, KafkaEvent } from "../../src/message";
 import { KAFKA_CE_HEADERS } from "../../src/message/kafka/headers";
@@ -43,7 +43,7 @@ const imageData = new Uint32Array(fs.readFileSync(path.join(process.cwd(), "test
 const image_base64 = asBase64(imageData);
 
 const fixture = new CloudEvent({
-  specversion: Version.V1,
+  specversion: V1,
   id,
   type,
   source,
@@ -233,7 +233,7 @@ describe("Kafka transport", () => {
     expect(message.body).to.equal(data);
     // validate all headers
     expect(message.headers[CONSTANTS.HEADER_CONTENT_TYPE]).to.equal(datacontenttype);
-    expect(message.headers[KAFKA_CE_HEADERS.SPEC_VERSION]).to.equal(Version.V1);
+    expect(message.headers[KAFKA_CE_HEADERS.SPEC_VERSION]).to.equal(V1);
     expect(message.headers[KAFKA_CE_HEADERS.ID]).to.equal(id);
     expect(message.headers[KAFKA_CE_HEADERS.TYPE]).to.equal(type);
     expect(message.headers[KAFKA_CE_HEADERS.SOURCE]).to.equal(source);
@@ -249,7 +249,7 @@ describe("Kafka transport", () => {
     expect(message.headers[CONSTANTS.HEADER_CONTENT_TYPE]).to.equal(CONSTANTS.DEFAULT_CE_CONTENT_TYPE);
     // Parse the message body as JSON, then validate the attributes
     const body = JSON.parse(message.body as string);
-    expect(body[CONSTANTS.CE_ATTRIBUTES.SPEC_VERSION]).to.equal(Version.V1);
+    expect(body[CONSTANTS.CE_ATTRIBUTES.SPEC_VERSION]).to.equal(V1);
     expect(body[CONSTANTS.CE_ATTRIBUTES.ID]).to.equal(id);
     expect(body[CONSTANTS.CE_ATTRIBUTES.TYPE]).to.equal(type);
     expect(body[CONSTANTS.CE_ATTRIBUTES.SOURCE]).to.equal(source);

test/integration/message_test.ts

@@ -8,7 +8,7 @@ import fs from "fs";
 
 import { expect } from "chai";
 import { IncomingHttpHeaders } from "http";
-import { CloudEvent, CONSTANTS, Version } from "../../src";
+import { CloudEvent, CONSTANTS, V1, V03 } from "../../src";
 import { asBase64 } from "../../src/event/validation";
 import { Message, HTTP } from "../../src/message";
 
@@ -154,7 +154,7 @@ describe("HTTP transport", () => {
         [CONSTANTS.CE_HEADERS.ID]: "1234",
         [CONSTANTS.CE_HEADERS.SOURCE]: "test",
         [CONSTANTS.CE_HEADERS.TYPE]: "test.event",
-        [CONSTANTS.CE_HEADERS.SPEC_VERSION]: Version.V1,
+        [CONSTANTS.CE_HEADERS.SPEC_VERSION]: V1,
         "ce-LUNCH": "tacos",
       },
     };
@@ -237,7 +237,7 @@ describe("HTTP transport", () => {
       id,
       type,
       source,
-      specversion: Version.V1,
+      specversion: V1,
       data: { lunch: "tacos" },
     });
     const message: Message<undefined> = {
@@ -250,7 +250,7 @@ describe("HTTP transport", () => {
 
   describe("Specification version V1", () => {
     const fixture = new CloudEvent({
-      specversion: Version.V1,
+      specversion: V1,
       id,
       type,
       source,
@@ -268,7 +268,7 @@ describe("HTTP transport", () => {
       expect(message.body).to.equal(JSON.stringify(data));
       // validate all headers
       expect(message.headers[CONSTANTS.HEADER_CONTENT_TYPE]).to.equal(datacontenttype);
-      expect(message.headers[CONSTANTS.CE_HEADERS.SPEC_VERSION]).to.equal(Version.V1);
+      expect(message.headers[CONSTANTS.CE_HEADERS.SPEC_VERSION]).to.equal(V1);
       expect(message.headers[CONSTANTS.CE_HEADERS.ID]).to.equal(id);
       expect(message.headers[CONSTANTS.CE_HEADERS.TYPE]).to.equal(type);
       expect(message.headers[CONSTANTS.CE_HEADERS.SOURCE]).to.equal(source);
@@ -284,7 +284,7 @@ describe("HTTP transport", () => {
       expect(message.headers[CONSTANTS.HEADER_CONTENT_TYPE]).to.equal(CONSTANTS.DEFAULT_CE_CONTENT_TYPE);
       // Parse the message body as JSON, then validate the attributes
       const body = JSON.parse(message.body as string);
-      expect(body[CONSTANTS.CE_ATTRIBUTES.SPEC_VERSION]).to.equal(Version.V1);
+      expect(body[CONSTANTS.CE_ATTRIBUTES.SPEC_VERSION]).to.equal(V1);
       expect(body[CONSTANTS.CE_ATTRIBUTES.ID]).to.equal(id);
       expect(body[CONSTANTS.CE_ATTRIBUTES.TYPE]).to.equal(type);
       expect(body[CONSTANTS.CE_ATTRIBUTES.SOURCE]).to.equal(source);
@@ -353,7 +353,7 @@ describe("HTTP transport", () => {
 
   describe("Specification version V03", () => {
     const fixture = new CloudEvent({
-      specversion: Version.V03,
+      specversion: V03,
       id,
       type,
       source,
@@ -371,7 +371,7 @@ describe("HTTP transport", () => {
       expect(message.body).to.equal(JSON.stringify(data));
       // validate all headers
       expect(message.headers[CONSTANTS.HEADER_CONTENT_TYPE]).to.equal(datacontenttype);
-      expect(message.headers[CONSTANTS.CE_HEADERS.SPEC_VERSION]).to.equal(Version.V03);
+      expect(message.headers[CONSTANTS.CE_HEADERS.SPEC_VERSION]).to.equal(V03);
       expect(message.headers[CONSTANTS.CE_HEADERS.ID]).to.equal(id);
       expect(message.headers[CONSTANTS.CE_HEADERS.TYPE]).to.equal(type);
       expect(message.headers[CONSTANTS.CE_HEADERS.SOURCE]).to.equal(source);
@@ -387,7 +387,7 @@ describe("HTTP transport", () => {
       expect(message.headers[CONSTANTS.HEADER_CONTENT_TYPE]).to.equal(CONSTANTS.DEFAULT_CE_CONTENT_TYPE);
       // Parse the message body as JSON, then validate the attributes
       const body = JSON.parse(message.body as string);
-      expect(body[CONSTANTS.CE_ATTRIBUTES.SPEC_VERSION]).to.equal(Version.V03);
+      expect(body[CONSTANTS.CE_ATTRIBUTES.SPEC_VERSION]).to.equal(V03);
       expect(body[CONSTANTS.CE_ATTRIBUTES.ID]).to.equal(id);
       expect(body[CONSTANTS.CE_ATTRIBUTES.TYPE]).to.equal(type);
       expect(body[CONSTANTS.CE_ATTRIBUTES.SOURCE]).to.equal(source);

test/integration/mqtt_tests.ts

@@ -7,7 +7,7 @@ import path from "path";
 import fs from "fs";
 
 import { expect } from "chai";
-import { CloudEvent, CONSTANTS, Version, Headers } from "../../src";
+import { CloudEvent, CONSTANTS, V1, Headers } from "../../src";
 import { asBase64 } from "../../src/event/validation";
 import { Message, MQTT, MQTTMessage } from "../../src/message";
 
@@ -43,7 +43,7 @@ const image_base64 = asBase64(imageData);
 const PUBLISH = {"Content Type": "application/json; charset=utf-8"};
 
 const fixture = new CloudEvent({
-  specversion: Version.V1,
+  specversion: V1,
   id,
   type,
   source,
@@ -216,7 +216,7 @@ describe("MQTT transport", () => {
     expect(message.body).to.equal(data);
     // validate all headers
     expect(message.headers.datacontenttype).to.equal(datacontenttype);
-    expect(message.headers.specversion).to.equal(Version.V1);
+    expect(message.headers.specversion).to.equal(V1);
     expect(message.headers.id).to.equal(id);
     expect(message.headers.type).to.equal(type);
     expect(message.headers.source).to.equal(source);
@@ -232,7 +232,7 @@ describe("MQTT transport", () => {
     expect(message.body).to.equal(data);
     // validate all headers
     expect(message["User Properties"]?.datacontenttype).to.equal(datacontenttype);
-    expect(message["User Properties"]?.specversion).to.equal(Version.V1);
+    expect(message["User Properties"]?.specversion).to.equal(V1);
     expect(message["User Properties"]?.id).to.equal(id);
     expect(message["User Properties"]?.type).to.equal(type);
     expect(message["User Properties"]?.source).to.equal(source);
@@ -249,7 +249,7 @@ describe("MQTT transport", () => {
     expect(message.body).to.deep.equal(message.payload);
     expect(message.payload).to.deep.equal(fixture.toJSON());
     const body = message.body as Record<string, string>;
-    expect(body[CONSTANTS.CE_ATTRIBUTES.SPEC_VERSION]).to.equal(Version.V1);
+    expect(body[CONSTANTS.CE_ATTRIBUTES.SPEC_VERSION]).to.equal(V1);
     expect(body[CONSTANTS.CE_ATTRIBUTES.ID]).to.equal(id);
     expect(body[CONSTANTS.CE_ATTRIBUTES.TYPE]).to.equal(type);
     expect(body[CONSTANTS.CE_ATTRIBUTES.SOURCE]).to.equal(source);