feat(UserAgent): introduce addAlgoliaAgent method (#105)

* feat(UserAgent): introduce addAlgoliaAgent method

This introduces a addAlgoliaAgent method that can be also found in the
search client.

```ts
aa('addAlgoliaAgent', 'a random string')
```

* feat(UserAgent): add space after ;

lib/__tests__/_algoliaAgent.test.ts

@@ -0,0 +1,40 @@
+import AlgoliaInsights from "../insights";
+
+jest.mock("../../package.json", () => ({ version: "1.0.1" }));
+
+describe("algoliaAgent", () => {
+  beforeEach(() => {
+    AlgoliaInsights.init({ apiKey: "test", appId: "test" });
+  });
+
+  it("should initialize the client with a default algoliaAgent string", () => {
+    expect(AlgoliaInsights._ua).toEqual(
+      "Algolia insights for JavaScript (1.0.1)"
+    );
+    expect(AlgoliaInsights._uaURIEncoded).toEqual(
+      "Algolia%20insights%20for%20JavaScript%20(1.0.1)"
+    );
+  });
+
+  it("should allow adding a string to algoliaAgent", () => {
+    AlgoliaInsights.addAlgoliaAgent("other string");
+    expect(AlgoliaInsights._ua).toEqual(
+      "Algolia insights for JavaScript (1.0.1); other string"
+    );
+    expect(AlgoliaInsights._uaURIEncoded).toEqual(
+      "Algolia%20insights%20for%20JavaScript%20(1.0.1)%3B%20other%20string"
+    );
+  });
+
+  it("should duplicate a string when added twice", () => {
+    AlgoliaInsights.addAlgoliaAgent("duplicated string");
+    AlgoliaInsights.addAlgoliaAgent("duplicated string");
+
+    expect(AlgoliaInsights._ua).toEqual(
+      "Algolia insights for JavaScript (1.0.1); duplicated string"
+    );
+    expect(AlgoliaInsights._uaURIEncoded).toEqual(
+      "Algolia%20insights%20for%20JavaScript%20(1.0.1)%3B%20duplicated%20string"
+    );
+  });
+});

lib/_algoliaAgent.ts

@@ -0,0 +1,10 @@
+import { version } from "../package.json";
+
+export const DEFAULT_ALGOLIA_AGENT = `Algolia insights for JavaScript (${version})`;
+
+export function addAlgoliaAgent(algoliaAgent) {
+  if (this._ua.indexOf(`; ${algoliaAgent}`) === -1) {
+    this._ua += `; ${algoliaAgent}`;
+    this._uaURIEncoded = encodeURIComponent(this._ua);
+  }
+}

lib/_sendEvent.ts

@@ -1,5 +1,4 @@
 import { isNumber, isUndefined, isString, isFunction } from "./utils";
-import { version } from "../package.json";
 
 export type InsightsEventType = "click" | "conversion" | "view";
 export type InsightsEvent = {
@@ -17,9 +16,6 @@ export type InsightsEvent = {
   filters?: string[];
 };
 
-const USER_AGENT = encodeURIComponent(
-  `Algolia insights for JavaScript (${version})`
-);
 /**
  *  Sends data to endpoint
  * @param eventType InsightsEventType
@@ -108,17 +104,18 @@ export function sendEvent(
     throw new Error("expected either `objectIDs` or `filters` to be provided");
   }
 
-  bulkSendEvent(this._appId, this._apiKey, this._endpointOrigin, [event]);
+  bulkSendEvent(this._appId, this._apiKey, this._uaURIEncoded, this._endpointOrigin, [event]);
 }
 
 function bulkSendEvent(
   appId: string,
   apiKey: string,
+  userAgent: string,
   endpointOrigin: string,
   events: InsightsEvent[]
 ) {
   // Auth query
-  const reportingURL = `${endpointOrigin}/1/events?X-Algolia-Application-Id=${appId}&X-Algolia-API-Key=${apiKey}&X-Algolia-Agent=${USER_AGENT}`;
+  const reportingURL = `${endpointOrigin}/1/events?X-Algolia-Application-Id=${appId}&X-Algolia-API-Key=${apiKey}&X-Algolia-Agent=${userAgent}`;
 
   // Detect navigator support
   const supportsNavigator = navigator && isFunction(navigator.sendBeacon);

lib/init.ts

@@ -1,4 +1,5 @@
 import { isUndefined, isString, isNumber } from "./utils";
+import { DEFAULT_ALGOLIA_AGENT } from "./_algoliaAgent";
 
 type InsightRegion = "de" | "us";
 const SUPPORTED_REGIONS: InsightRegion[] = ["de", "us"];
@@ -66,4 +67,8 @@ export function init(options: InitParams) {
     : 6 * MONTH;
   // Set hasCredentials
   this._hasCredentials = true;
+
+  // user agent
+  this._ua = DEFAULT_ALGOLIA_AGENT;
+  this._uaURIEncoded = encodeURIComponent(DEFAULT_ALGOLIA_AGENT);
 }

lib/insights.ts

@@ -9,6 +9,8 @@ import { sendEvent, InsightsEventType, InsightsEvent } from "./_sendEvent";
 
 import { InitParams, init } from "./init";
 import { initSearch, InitSearchParams } from "./_initSearch";
+import { addAlgoliaAgent } from "./_algoliaAgent";
+
 import {
   InsightsSearchClickEvent,
   clickedObjectIDsAfterSearch,
@@ -66,6 +68,10 @@ class AlgoliaAnalytics {
   _userHasOptedOut: boolean;
   _cookieDuration: number;
 
+  // user agent
+  _ua: string = "";
+  _uaURIEncoded: string = "";
+
   version: string = version;
 
   // Private methods
@@ -80,6 +86,8 @@ class AlgoliaAnalytics {
   public init: (params: InitParams) => void;
   public initSearch: (params: InitSearchParams) => void;
 
+  public addAlgoliaAgent: (algoliaAgent: string) => void;
+
   public ANONYMOUS_USER_TOKEN: string;
   public setUserToken: (userToken: string) => void;
   public getUserToken: () => string;
@@ -111,6 +119,8 @@ class AlgoliaAnalytics {
     this.init = init.bind(this);
     this.initSearch = initSearch.bind(this);
 
+    this.addAlgoliaAgent = addAlgoliaAgent.bind(this);
+
     this.ANONYMOUS_USER_TOKEN = ANONYMOUS_USER_TOKEN;
     this.setUserToken = setUserToken.bind(this);
     this.getUserToken = getUserToken.bind(this);