chore: implement initial flag fetch (#294)

First attempt to implement an initial flag fetch followed by emitting events. I also added comments like this: ```tsx Dom api usage: xxx ``` There are three right now: fetch, btoa and EventTarget. I left comments in the code for react native how to deal with these. --------- Co-authored-by: LaunchDarklyReleaseBot <[email protected]> Co-authored-by: Ryan Lamb <[email protected]>
launchdarkly · Oct 10, 2023 · 8f34dfa · 8f34dfa
1 parent a0dac0d
commit 8f34dfa
Show file tree

Hide file tree

Showing 27 changed files with 623 additions and 73 deletions.
diff --git a/contract-tests/sdkClientEntity.js b/contract-tests/sdkClientEntity.js
@@ -1,11 +1,11 @@
 import got from 'got';
 import ld, {
+  createMigration,
   LDConcurrentExecution,
   LDExecutionOrdering,
   LDMigrationError,
   LDMigrationSuccess,
   LDSerialExecution,
-  createMigration,
 } from 'node-server-sdk';
 
 import BigSegmentTestStore from './BigSegmentTestStore.js';
@@ -17,7 +17,7 @@ export { badCommandError };
 export function makeSdkConfig(options, tag) {
   const cf = {
     logger: sdkLogger(tag),
-    diagnosticOptOut: true
+    diagnosticOptOut: true,
   };
   const maybeTime = (seconds) =>
     seconds === undefined || seconds === null ? undefined : seconds / 1000;
@@ -125,29 +125,64 @@ export async function newSdkClientEntity(options) {
       case 'evaluate': {
         const pe = params.evaluate;
         if (pe.detail) {
-          switch(pe.valueType) {
-            case "bool":
-              return await client.boolVariationDetail(pe.flagKey, pe.context || pe.user, pe.defaultValue);
-            case "int": // Intentional fallthrough.
-            case "double":
-              return await client.numberVariationDetail(pe.flagKey, pe.context || pe.user, pe.defaultValue);
-            case "string":
-              return await client.stringVariationDetail(pe.flagKey, pe.context || pe.user, pe.defaultValue);
+          switch (pe.valueType) {
+            case 'bool':
+              return await client.boolVariationDetail(
+                pe.flagKey,
+                pe.context || pe.user,
+                pe.defaultValue,
+              );
+            case 'int': // Intentional fallthrough.
+            case 'double':
+              return await client.numberVariationDetail(
+                pe.flagKey,
+                pe.context || pe.user,
+                pe.defaultValue,
+              );
+            case 'string':
+              return await client.stringVariationDetail(
+                pe.flagKey,
+                pe.context || pe.user,
+                pe.defaultValue,
+              );
             default:
-              return await client.variationDetail(pe.flagKey, pe.context || pe.user, pe.defaultValue);
+              return await client.variationDetail(
+                pe.flagKey,
+                pe.context || pe.user,
+                pe.defaultValue,
+              );
           }
-
         } else {
-          switch(pe.valueType) {
-            case "bool":
-              return {value: await client.boolVariation(pe.flagKey, pe.context || pe.user, pe.defaultValue)};
-            case "int": // Intentional fallthrough.
-            case "double":
-              return {value: await client.numberVariation(pe.flagKey, pe.context || pe.user, pe.defaultValue)};
-            case "string":
-              return {value: await client.stringVariation(pe.flagKey, pe.context || pe.user, pe.defaultValue)};
+          switch (pe.valueType) {
+            case 'bool':
+              return {
+                value: await client.boolVariation(
+                  pe.flagKey,
+                  pe.context || pe.user,
+                  pe.defaultValue,
+                ),
+              };
+            case 'int': // Intentional fallthrough.
+            case 'double':
+              return {
+                value: await client.numberVariation(
+                  pe.flagKey,
+                  pe.context || pe.user,
+                  pe.defaultValue,
+                ),
+              };
+            case 'string':
+              return {
+                value: await client.stringVariation(
+                  pe.flagKey,
+                  pe.context || pe.user,
+                  pe.defaultValue,
+                ),
+              };
             default:
-              return {value: await client.variation(pe.flagKey, pe.context || pe.user, pe.defaultValue)};
+              return {
+                value: await client.variation(pe.flagKey, pe.context || pe.user, pe.defaultValue),
+              };
           }
         }
       }

diff --git a/packages/shared/common/src/api/platform/Encoding.ts b/packages/shared/common/src/api/platform/Encoding.ts
@@ -0,0 +1,3 @@
+export interface Encoding {
+  btoa(data: string): string;
+}
diff --git a/packages/shared/common/src/api/platform/Platform.ts b/packages/shared/common/src/api/platform/Platform.ts
@@ -1,9 +1,15 @@
 import { Crypto } from './Crypto';
+import { Encoding } from './Encoding';
 import { Filesystem } from './Filesystem';
 import { Info } from './Info';
 import { Requests } from './Requests';
 
 export interface Platform {
+  /**
+   * The interface for performing encoding operations.
+   */
+  encoding?: Encoding;
+
   /**
    * The interface for getting information about the platform and the execution
    * environment.

diff --git a/packages/shared/common/src/api/platform/index.ts b/packages/shared/common/src/api/platform/index.ts
@@ -1,3 +1,4 @@
+export * from './Encoding';
 export * from './Crypto';
 export * from './Filesystem';
 export * from './Info';

diff --git a/packages/shared/mocks/src/clientContext.ts b/packages/shared/mocks/src/clientContext.ts
@@ -1,13 +1,13 @@
 import type { ClientContext } from '@common';
 
-import platform from './platform';
+import basicPlatform from './platform';
 
 const clientContext: ClientContext = {
   basicConfiguration: {
     sdkKey: 'testSdkKey',
     serviceEndpoints: { events: '', polling: '', streaming: 'https://mockstream.ld.com' },
   },
-  platform,
+  platform: basicPlatform,
 };
 
 export default clientContext;
diff --git a/packages/shared/mocks/src/index.ts b/packages/shared/mocks/src/index.ts
@@ -2,12 +2,14 @@ import clientContext from './clientContext';
 import ContextDeduplicator from './contextDeduplicator';
 import { crypto, hasher } from './hasher';
 import logger from './logger';
+import mockFetch from './mockFetch';
 import basicPlatform from './platform';
 import { MockStreamingProcessor, setupMockStreamingProcessor } from './streamingProcessor';
 
 export {
   basicPlatform,
   clientContext,
+  mockFetch,
   crypto,
   logger,
   hasher,

diff --git a/packages/shared/mocks/src/mockFetch.ts b/packages/shared/mocks/src/mockFetch.ts
@@ -0,0 +1,32 @@
+import { Response } from '@common';
+
+import basicPlatform from './platform';
+
+const createMockResponse = (remoteJson: any, statusCode: number) => {
+  const response: Response = {
+    headers: {
+      get: jest.fn(),
+      keys: jest.fn(),
+      values: jest.fn(),
+      entries: jest.fn(),
+      has: jest.fn(),
+    },
+    status: statusCode,
+    text: jest.fn(),
+    json: () => Promise.resolve(remoteJson),
+  };
+  return Promise.resolve(response);
+};
+
+/**
+ * Mocks basicPlatform fetch. Returns the fetch jest.Mock object.
+ * @param remoteJson
+ * @param statusCode
+ */
+const mockFetch = (remoteJson: any, statusCode: number = 200): jest.Mock => {
+  const f = basicPlatform.requests.fetch as jest.Mock;
+  f.mockResolvedValue(createMockResponse(remoteJson, statusCode));
+  return f;
+};
+
+export default mockFetch;
diff --git a/packages/shared/mocks/src/platform.ts b/packages/shared/mocks/src/platform.ts
@@ -1,7 +1,11 @@
-import type { Info, Platform, PlatformData, Requests, SdkData } from '@common';
+import type { Encoding, Info, Platform, PlatformData, Requests, SdkData } from '@common';
 
 import { crypto } from './hasher';
 
+const encoding: Encoding = {
+  btoa: (s: string) => Buffer.from(s).toString('base64'),
+};
+
 const info: Info = {
   platformData(): PlatformData {
     return {
@@ -33,6 +37,7 @@ const requests: Requests = {
 };
 
 const basicPlatform: Platform = {
+  encoding,
   info,
   crypto,
   requests,

diff --git a/packages/shared/sdk-client/package.json b/packages/shared/sdk-client/package.json
@@ -34,6 +34,7 @@
     "semver": "7.5.4"
   },
   "devDependencies": {
+    "@launchdarkly/private-js-mocks": "0.0.1",
     "@testing-library/dom": "^9.3.1",
     "@testing-library/jest-dom": "^5.16.5",
     "@types/jest": "^29.5.3",

diff --git a/.../shared/sdk-client/src/LDClientDomImpl.ts → ...ges/shared/sdk-client/src/LDClientImpl.ts b/.../shared/sdk-client/src/LDClientDomImpl.ts → ...ges/shared/sdk-client/src/LDClientImpl.ts
@@ -2,37 +2,76 @@
 
 /* eslint-disable @typescript-eslint/no-unused-vars */
 import {
+  Context,
   internal,
   LDContext,
   LDEvaluationDetail,
   LDFlagSet,
   LDFlagValue,
+  LDLogger,
+  Platform,
   subsystem,
 } from '@launchdarkly/js-sdk-common';
 
-import { LDClientDom } from './api/LDClientDom';
+import { LDClient } from './api/LDClient';
+import LDEmitter, { EventName } from './api/LDEmitter';
 import LDOptions from './api/LDOptions';
 import Configuration from './configuration';
 import createDiagnosticsManager from './diagnostics/createDiagnosticsManager';
+import fetchFlags, { Flags } from './evaluation/fetchFlags';
 import createEventProcessor from './events/createEventProcessor';
-import { PlatformDom, Storage } from './platform/PlatformDom';
 
-export default class LDClientDomImpl implements LDClientDom {
+export default class LDClientImpl implements LDClient {
   config: Configuration;
   diagnosticsManager?: internal.DiagnosticsManager;
   eventProcessor: subsystem.LDEventProcessor;
-  storage: Storage;
+  private emitter: LDEmitter;
+  private flags: Flags = {};
+  private logger: LDLogger;
+
+  /**
+   * Creates the client object synchronously. No async, no network calls.
+   */
+  constructor(
+    public readonly sdkKey: string,
+    public readonly context: LDContext,
+    public readonly platform: Platform,
+    options: LDOptions,
+  ) {
+    if (!sdkKey) {
+      throw new Error('You must configure the client with a client-side SDK key');
+    }
+
+    const checkedContext = Context.fromLDContext(context);
+    if (!checkedContext.valid) {
+      throw new Error('Context was unspecified or had no key');
+    }
+
+    if (!platform.encoding) {
+      throw new Error('Platform must implement Encoding because btoa is required.');
+    }
 
-  constructor(clientSideID: string, context: LDContext, options: LDOptions, platform: PlatformDom) {
     this.config = new Configuration(options);
-    this.storage = platform.storage;
-    this.diagnosticsManager = createDiagnosticsManager(clientSideID, this.config, platform);
+    this.logger = this.config.logger;
+    this.diagnosticsManager = createDiagnosticsManager(sdkKey, this.config, platform);
     this.eventProcessor = createEventProcessor(
-      clientSideID,
+      sdkKey,
       this.config,
       platform,
       this.diagnosticsManager,
     );
+    this.emitter = new LDEmitter();
+  }
+
+  async start() {
+    try {
+      this.flags = await fetchFlags(this.sdkKey, this.context, this.config, this.platform);
+      this.emitter.emit('ready');
+    } catch (error: any) {
+      this.logger.error(error);
+      this.emitter.emit('error', error);
+      this.emitter.emit('failed', error);
+    }
   }
 
   allFlags(): LDFlagSet {
@@ -59,9 +98,13 @@ export default class LDClientDomImpl implements LDClientDom {
     return Promise.resolve({});
   }
 
-  off(key: string, callback: (...args: any[]) => void, context?: any): void {}
+  off(eventName: EventName, listener?: Function): void {
+    this.emitter.off(eventName, listener);
+  }
 
-  on(key: string, callback: (...args: any[]) => void, context?: any): void {}
+  on(eventName: EventName, listener: Function): void {
+    this.emitter.on(eventName, listener);
+  }
 
   setStreaming(value?: boolean): void {}
 

diff --git a/.../shared/sdk-client/src/api/LDClientDom.ts → ...ges/shared/sdk-client/src/api/LDClient.ts b/.../shared/sdk-client/src/api/LDClientDom.ts → ...ges/shared/sdk-client/src/api/LDClient.ts
@@ -7,7 +7,7 @@ import { LDContext, LDEvaluationDetail, LDFlagSet, LDFlagValue } from '@launchda
  *
  * @ignore (don't need to show this separately in TypeDoc output; all methods will be shown in LDClient)
  */
-export interface LDClientDom {
+export interface LDClient {
   /**
    * Returns a Promise that tracks the client's initialization state.
    *
@@ -172,7 +172,7 @@ export interface LDClientDom {
    *
    * If this is true, the client will always attempt to maintain a streaming connection; if false,
    * it never will. If you leave the value undefined (the default), the client will open a streaming
-   * connection if you subscribe to `"change"` or `"change:flag-key"` events (see {@link LDClientDom.on}).
+   * connection if you subscribe to `"change"` or `"change:flag-key"` events (see {@link LDClient.on}).
    *
    * This can also be set as the `streaming` property of {@link LDOptions}.
    */
@@ -206,7 +206,7 @@ export interface LDClientDom {
    * The `"change"` and `"change:FLAG-KEY"` events have special behavior: by default, the
    * client will open a streaming connection to receive live changes if and only if
    * you are listening for one of these events. This behavior can be overridden by
-   * setting `streaming` in {@link LDOptions} or calling {@link LDClientDom.setStreaming}.
+   * setting `streaming` in {@link LDOptions} or calling {@link LDClient.setStreaming}.
    *
    * @param key
    *   The name of the event for which to listen.