better example of 'beforeEach' with service

Author: mhoeger

samples/http/app.ts

@@ -5,7 +5,7 @@ import { HostOptions } from "../../src/hostConfig"
 import { InvocationContext } from "./common/interfaces"
 import { sayHello } from "./functions/hello"
 import { sayGoodbye } from "./functions/goodbye"
-import { CosmosClient } from "./services/fake-clients"
+import { getExampleClient } from "./services/fake-clients"
 
 const functions: AzureFunctionDefinition[] = [
     {
@@ -25,7 +25,7 @@ const functions: AzureFunctionDefinition[] = [
             })
         ],
     },
-    { 
+    {
         trigger: new HttpTrigger({
             bindingName: "req",
             route: "/order",
@@ -65,15 +65,16 @@ const options: HostOptions = {
 };
 
 // - local.settings.json??? also host.json not needed??
-const app = new FunctionApp(functions, options);
+const app = new FunctionApp({
+    functions,
+    options
+});
 // before each function, do this
 // beforeeach on trigger type
 // for
-let cosmosClient = new CosmosClient();
-
 app.beforeEach(async (context: InvocationContext) => {
     context.log(`~~ Starting invocation: '${context.invocationId}' ~~`);
-    context.cosmosClient = cosmosClient;
+    context.exampleClient = getExampleClient();
 });
 
 app.beforeEach(async (context: InvocationContext) => {

samples/http/common/interfaces.ts

@@ -1,9 +1,9 @@
 import { Context, HttpRequest } from "@azure/functions"
+import { ExampleClient } from "../services/fake-clients";
 
 export interface InvocationContext extends Context {
     name: string;
-    cosmosClient: any;
-    req: CookieRequest;
+    exampleClient: ExampleClient;
 }
 
 interface CookieRequest extends HttpRequest {

samples/http/services/fake-clients.ts

@@ -1,3 +1,13 @@
-export class CosmosClient {
-    getContainers() { return "Fake cosmos client call"; }
-};
+// This would typically be from some other library
+export class ExampleClient {
+    getData() { return "Fake data fetched from fake service"; }
+};
+
+let _client: ExampleClient;
+
+export function getExampleClient() {
+    if (!_client) {
+        _client = new ExampleClient();
+    }
+    return _client;
+}

src/azure-functions.ts

@@ -29,7 +29,8 @@ export class FunctionApp {
     };
 
     // host.json and local.settings.json... what to do??
-    constructor(functions: AzureFunctionDefinition[], options?: HostOptions) {
+    constructor(setup: { functions: AzureFunctionDefinition[], options?: HostOptions }) {
+        let { functions, options } = setup; 
         this._functionConfigurations = functions;
         this._hostOptions = Object.assign({}, this.defaultHostOptions, options, this.requiredHostOptions);        
         for (const func of functions) {