Change type info to be inheritance friendly. (#1091)

Unwind the cleverness of CloudEvent<EventType, Extensions>. Types
now match the approved format of the Python API. CloudFunction now
templatizes the CloudEvent rather than the EventType so that we can
keep typing to include subtypes of events both in code complete and
in firebase-functions-test.

Author: inlined

src/v2/core.ts

@@ -57,7 +57,7 @@ export interface TriggerAnnotation {
  * A CloudEventBase is the base of a cross-platform format for encoding a serverless event.
  * More information can be found in https://github.com/cloudevents/spec
  */
-interface CloudEventBase<T> {
+export interface CloudEvent<T> {
   /** Version of the CloudEvents spec for this event. */
   readonly specversion: '1.0';
 
@@ -78,32 +78,14 @@ interface CloudEventBase<T> {
 
   /** Information about this specific event. */
   data: T;
-
-  /**
-   * A map of template parameter name to value for subject strings.
-   *
-   * This map is only available on some event types that allow templates
-   * in the subject string, such as Firestore. When listening to a document
-   * template "/users/{uid}", an event with subject "/documents/users/1234"
-   * would have a params of {"uid": "1234"}.
-   *
-   * Params are generated inside the firebase-functions SDK and are not
-   * part of the CloudEvents spec nor the payload that a Cloud Function
-   * actually receives.
-   */
-  params?: Record<string, string>;
 }
 
-/**
- * A CloudEvent with custom extension attributes
- */
-export type CloudEvent<T = any, Ext = {}> = CloudEventBase<T> & Ext;
 /** A handler for CloudEvents. */
-export interface CloudFunction<T> {
+export interface CloudFunction<EventType extends CloudEvent<unknown>> {
   (raw: CloudEvent<unknown>): any | Promise<any>;
 
   __trigger?: unknown;
   __endpoint: ManifestEndpoint;
 
-  run(event: CloudEvent<T>): any | Promise<any>;
+  run(event: EventType): any | Promise<any>;
 }

src/v2/providers/alerts/alerts.ts

@@ -14,22 +14,21 @@ export interface FirebaseAlertData<T = any> {
   payload: T;
 }
 
-interface WithAlertTypeAndApp {
+/**
+ * A custom CloudEvent for Firebase Alerts (with custom extension attributes).
+ */
+export interface AlertEvent<T> extends CloudEvent<FirebaseAlertData<T>> {
   /** The type of the alerts that got triggered. */
   alertType: string;
   /**
    * The Firebase App ID that’s associated with the alert. This is optional,
    * and only present when the alert is targeting at a specific Firebase App.
    */
   appId?: string;
+
+  /** Data for an AlertEvent is a FirebaseAlertData with a given payload. */
+  data: FirebaseAlertData<T>;
 }
-/**
- * A custom CloudEvent for Firebase Alerts (with custom extension attributes).
- */
-export type AlertEvent<T> = CloudEvent<
-  FirebaseAlertData<T>,
-  WithAlertTypeAndApp
->;
 
 /** @internal */
 export const eventType = 'google.firebase.firebasealerts.alerts.v1.published';
@@ -63,13 +62,11 @@ export interface FirebaseAlertOptions extends options.EventHandlerOptions {
 export function onAlertPublished<T extends { ['@type']: string } = any>(
   alertTypeOrOpts: AlertType | FirebaseAlertOptions,
   handler: (event: AlertEvent<T>) => any | Promise<any>
-): CloudFunction<FirebaseAlertData<T>> {
+): CloudFunction<AlertEvent<T>> {
   const [opts, alertType, appId] = getOptsAndAlertTypeAndApp(alertTypeOrOpts);
 
   const func = (raw: CloudEvent<unknown>) => {
-    return handler(
-      raw as CloudEvent<FirebaseAlertData<T>, WithAlertTypeAndApp>
-    );
+    return handler(raw as AlertEvent<T>);
   };
 
   func.run = handler;

src/v2/providers/alerts/appDistribution.ts

@@ -14,19 +14,16 @@ export interface NewTesterDevicePayload {
   testerDeviceIdentifier: string;
 }
 
-interface WithAlertTypeAndApp {
+/**
+ * A custom CloudEvent for Firebase Alerts (with custom extension attributes).
+ */
+export interface AppDistributionEvent<T>
+  extends CloudEvent<FirebaseAlertData<T>> {
   /** The type of the alerts that got triggered. */
   alertType: string;
   /** The Firebase App ID that’s associated with the alert. */
   appId: string;
 }
-/**
- * A custom CloudEvent for Firebase Alerts (with custom extension attributes).
- */
-export type AppDistributionEvent<T> = CloudEvent<
-  FirebaseAlertData<T>,
-  WithAlertTypeAndApp
->;
 
 /** @internal */
 export const newTesterIosDeviceAlert = 'appDistribution.newTesterIosDevice';
@@ -45,19 +42,19 @@ export function onNewTesterIosDevicePublished(
   handler: (
     event: AppDistributionEvent<NewTesterDevicePayload>
   ) => any | Promise<any>
-): CloudFunction<FirebaseAlertData<NewTesterDevicePayload>>;
+): CloudFunction<AppDistributionEvent<NewTesterDevicePayload>>;
 export function onNewTesterIosDevicePublished(
   appId: string,
   handler: (
     event: AppDistributionEvent<NewTesterDevicePayload>
   ) => any | Promise<any>
-): CloudFunction<FirebaseAlertData<NewTesterDevicePayload>>;
+): CloudFunction<AppDistributionEvent<NewTesterDevicePayload>>;
 export function onNewTesterIosDevicePublished(
   opts: AppDistributionOptions,
   handler: (
     event: AppDistributionEvent<NewTesterDevicePayload>
   ) => any | Promise<any>
-): CloudFunction<FirebaseAlertData<NewTesterDevicePayload>>;
+): CloudFunction<AppDistributionEvent<NewTesterDevicePayload>>;
 export function onNewTesterIosDevicePublished(
   appIdOrOptsOrHandler:
     | string
@@ -68,7 +65,7 @@ export function onNewTesterIosDevicePublished(
   handler?: (
     event: AppDistributionEvent<NewTesterDevicePayload>
   ) => any | Promise<any>
-): CloudFunction<FirebaseAlertData<NewTesterDevicePayload>> {
+): CloudFunction<AppDistributionEvent<NewTesterDevicePayload>> {
   if (typeof appIdOrOptsOrHandler === 'function') {
     handler = appIdOrOptsOrHandler as (
       event: AppDistributionEvent<NewTesterDevicePayload>

src/v2/providers/alerts/billing.ts

@@ -28,14 +28,13 @@ export interface PlanAutomatedUpdatePayload {
   notificationType: string;
 }
 
-interface WithAlertType {
-  /** The type of the alerts that got triggered. */
-  alertType: string;
-}
 /**
  * A custom CloudEvent for billing Firebase Alerts (with custom extension attributes).
  */
-export type BillingEvent<T> = CloudEvent<FirebaseAlertData<T>, WithAlertType>;
+export interface BillingEvent<T> extends CloudEvent<FirebaseAlertData<T>> {
+  /** The type of the alerts that got triggered. */
+  alertType: string;
+}
 
 /** @internal */
 export const planUpdateAlert = 'billing.planUpdate';
@@ -47,17 +46,17 @@ export const planAutomatedUpdateAlert = 'billing.planAutomatedUpdate';
  */
 export function onPlanUpdatePublished(
   handler: (event: BillingEvent<PlanUpdatePayload>) => any | Promise<any>
-): CloudFunction<FirebaseAlertData<PlanUpdatePayload>>;
+): CloudFunction<BillingEvent<PlanUpdatePayload>>;
 export function onPlanUpdatePublished(
   opts: options.EventHandlerOptions,
   handler: (event: BillingEvent<PlanUpdatePayload>) => any | Promise<any>
-): CloudFunction<FirebaseAlertData<PlanUpdatePayload>>;
+): CloudFunction<BillingEvent<PlanUpdatePayload>>;
 export function onPlanUpdatePublished(
   optsOrHandler:
     | options.EventHandlerOptions
     | ((event: BillingEvent<PlanUpdatePayload>) => any | Promise<any>),
   handler?: (event: BillingEvent<PlanUpdatePayload>) => any | Promise<any>
-): CloudFunction<FirebaseAlertData<PlanUpdatePayload>> {
+): CloudFunction<BillingEvent<PlanUpdatePayload>> {
   return onOperation<PlanUpdatePayload>(
     planUpdateAlert,
     optsOrHandler,
@@ -72,21 +71,21 @@ export function onPlanAutomatedUpdatePublished(
   handler: (
     event: BillingEvent<PlanAutomatedUpdatePayload>
   ) => any | Promise<any>
-): CloudFunction<FirebaseAlertData<PlanAutomatedUpdatePayload>>;
+): CloudFunction<BillingEvent<PlanAutomatedUpdatePayload>>;
 export function onPlanAutomatedUpdatePublished(
   opts: options.EventHandlerOptions,
   handler: (
     event: BillingEvent<PlanAutomatedUpdatePayload>
   ) => any | Promise<any>
-): CloudFunction<FirebaseAlertData<PlanAutomatedUpdatePayload>>;
+): CloudFunction<BillingEvent<PlanAutomatedUpdatePayload>>;
 export function onPlanAutomatedUpdatePublished(
   optsOrHandler:
     | options.EventHandlerOptions
     | ((event: BillingEvent<PlanAutomatedUpdatePayload>) => any | Promise<any>),
   handler?: (
     event: BillingEvent<PlanAutomatedUpdatePayload>
   ) => any | Promise<any>
-): CloudFunction<FirebaseAlertData<PlanAutomatedUpdatePayload>> {
+): CloudFunction<BillingEvent<PlanAutomatedUpdatePayload>> {
   return onOperation<PlanAutomatedUpdatePayload>(
     planAutomatedUpdateAlert,
     optsOrHandler,
@@ -101,7 +100,7 @@ export function onOperation<T>(
     | options.EventHandlerOptions
     | ((event: BillingEvent<T>) => any | Promise<any>),
   handler: (event: BillingEvent<T>) => any | Promise<any>
-): CloudFunction<FirebaseAlertData<T>> {
+): CloudFunction<BillingEvent<T>> {
   if (typeof optsOrHandler === 'function') {
     handler = optsOrHandler as (event: BillingEvent<T>) => any | Promise<any>;
     optsOrHandler = {};