feat(EAV-243): add OAuth (Client Credentials grant) and Bearer Token …

…to HTTPSend
nrkno · May 24, 2024 · 8fef807 · 8fef807
1 parent 0ad6b7a
commit 8fef807
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Showing 3 changed files with 96 additions and 25 deletions.
diff --git a/packages/timeline-state-resolver-types/src/generated/httpSend.ts b/packages/timeline-state-resolver-types/src/generated/httpSend.ts
@@ -19,6 +19,7 @@ export interface HTTPSendOptions {
 	oauthClientId?: string
 	oauthClientSecret?: string
 	oauthAudience?: string
+	bearerToken?: string
 }
 export interface HTTPSendCommandContent {
 	type: TimelineContentTypeHTTP

diff --git a/packages/timeline-state-resolver/src/integrations/httpSend/$schemas/options.json b/packages/timeline-state-resolver/src/integrations/httpSend/$schemas/options.json
@@ -74,19 +74,25 @@
 		},
 		"oauthTokenHost": {
 			"type": "string",
-			"ui:title": "OAuth Token Host"
+			"ui:title": "OAuth 2.0 Token Host",
+			"ui:description": "To use Client Credentials Flow, provide: OAuth 2.0 Token Host, OAuth 2.0 Client ID, OAuth 2.0 Client Secret, and optionally OAuth 2.0 Audience, to exchange them for a Bearer token that will be added to EVERY outgoing request made through this device"
 		},
 		"oauthClientId": {
 			"type": "string",
-			"ui:title": "OAuth Client ID"
+			"ui:title": "OAuth 2.0 Client ID"
 		},
 		"oauthClientSecret": {
 			"type": "string",
-			"ui:title": "OAuth Client Secret"
+			"ui:title": "OAuth 2.0 Client Secret"
 		},
 		"oauthAudience": {
 			"type": "string",
-			"ui:title": "OAuth Audience"
+			"ui:title": "OAuth 2.0 Audience"
+		},
+		"bearerToken": {
+			"type": "string",
+			"ui:title": "Bearer Token",
+			"ui:descrption": "Long-lived Bearer token that will be added to EVERY outgoing request made through this device"
 		}
 	},
 	"required": ["host"],

diff --git a/packages/timeline-state-resolver/src/integrations/httpSend/AuthenticatedHTTPSendDevice.ts b/packages/timeline-state-resolver/src/integrations/httpSend/AuthenticatedHTTPSendDevice.ts
@@ -2,34 +2,98 @@ import { HTTPSendOptions } from 'timeline-state-resolver-types'
 import { HTTPSendDevice, HttpSendDeviceCommand } from '.'
 import { AccessToken, ClientCredentials } from 'simple-oauth2'
 
+const TOKEN_REQUEST_RETRY_TIMEOUT_MS = 1000
+const TOKEN_EXPIRATION_WINDOW_SEC = 60
+const enum AuthMethod {
+	BEARER_TOKEN,
+	CLIENT_CREDENTIALS,
+}
+
 export class AuthenticatedHTTPSendDevice extends HTTPSendDevice {
 	private tokenPromise: Promise<AccessToken> | undefined
-	private authOptions: { clientId: string; clientSecret: string; tokenHost: string; audience?: string } | undefined
+	private tokenRequestPending = false
+	private authOptions:
+		| {
+				method: AuthMethod.CLIENT_CREDENTIALS
+				clientId: string
+				clientSecret: string
+				tokenHost: string
+				audience?: string
+		  }
+		| { method: AuthMethod.BEARER_TOKEN; bearerToken: string }
+		| undefined
+	private tokenRefreshTimeout: NodeJS.Timeout | undefined
 
 	async init(options: HTTPSendOptions): Promise<boolean> {
-		if (options.oauthClientId && options.oauthClientSecret && options.oauthTokenHost) {
+		if (options.bearerToken) {
 			this.authOptions = {
+				method: AuthMethod.BEARER_TOKEN,
+				bearerToken: options.bearerToken,
+			}
+		} else if (options.oauthClientId && options.oauthClientSecret && options.oauthTokenHost) {
+			this.authOptions = {
+				method: AuthMethod.CLIENT_CREDENTIALS,
 				clientId: options.oauthClientId,
 				clientSecret: options.oauthClientSecret,
 				audience: options.oauthAudience,
 				tokenHost: options.oauthTokenHost,
 			}
-			const promise = this.requestAccessToken()
-			promise.catch(
-				(e) => {
-					this.emit('error', 'AuthenticatedHTTPSendDevice', e)
-				}
-				// retry
-			)
-			this.tokenPromise = promise
+			this.requestAccessToken()
 		}
 		return super.init(options)
 	}
 
-	async requestAccessToken(): Promise<AccessToken> {
-		if (!this.authOptions) {
-			throw Error('authOptions missing')
+	async terminate() {
+		this.clearTokenRefreshTimeout()
+		return super.terminate()
+	}
+
+	private requestAccessToken(): void {
+		if (this.tokenRequestPending) return
+		this.clearTokenRefreshTimeout()
+		this.tokenRequestPending = true
+		const promise = this.makeAccessTokenRequest()
+		promise
+			.then((accessToken) => {
+				this.emit('debug', `token received`)
+				const expiresIn = accessToken.token.expires_in
+				if (typeof expiresIn === 'number') {
+					this.scheduleTokenRefresh(expiresIn)
+				}
+			})
+			.catch((e) => {
+				this.emit('error', 'AuthenticatedHTTPSendDevice', e)
+				setTimeout(() => this.requestAccessToken(), TOKEN_REQUEST_RETRY_TIMEOUT_MS)
+			})
+			.finally(() => {
+				this.tokenRequestPending = false
+			})
+		this.tokenPromise = promise
+	}
+
+	private clearTokenRefreshTimeout() {
+		if (this.tokenRefreshTimeout) {
+			clearTimeout(this.tokenRefreshTimeout)
 		}
+	}
+
+	private scheduleTokenRefresh(expiresInSec: number) {
+		const timeoutMs = (expiresInSec - TOKEN_EXPIRATION_WINDOW_SEC) * 1000
+		this.emit('debug', `token refresh scheduled in ${timeoutMs}`)
+		this.tokenRefreshTimeout = setTimeout(() => this.refreshAccessToken(), timeoutMs)
+	}
+
+	private refreshAccessToken(): void {
+		this.emit('debug', `token refresh`)
+		this.requestAccessToken()
+		this.tokenRefreshTimeout = undefined
+	}
+
+	private async makeAccessTokenRequest(): Promise<AccessToken> {
+		if (!this.authOptions || this.authOptions.method !== AuthMethod.CLIENT_CREDENTIALS) {
+			throw Error('authOptions missing or incorrect')
+		}
+		this.emit('debug', 'token request')
 		const token = await new ClientCredentials({
 			client: {
 				id: this.authOptions.clientId,
@@ -38,23 +102,23 @@ export class AuthenticatedHTTPSendDevice extends HTTPSendDevice {
 			auth: {
 				tokenHost: this.authOptions.tokenHost,
 			},
-		}).getToken({})
+		}).getToken({
+			audience: this.authOptions.audience,
+		})
 		return token
 	}
 
 	async sendCommand({ tlObjId, context, command }: HttpSendDeviceCommand): Promise<void> {
-		if (this.options) {
-			const bearerToken = await this.tokenPromise
+		if (this.authOptions) {
+			const bearerToken =
+				this.authOptions.method === AuthMethod.BEARER_TOKEN ? this.authOptions.bearerToken : await this.tokenPromise
 			if (bearerToken) {
-				if (bearerToken.expired()) {
-					// todo: this should happen only once
-					this.tokenPromise = bearerToken.refresh()
-				}
+				const bearerHeader = `Bearer ${typeof bearerToken === 'string' ? bearerToken : bearerToken.token.access_token}`
 				command = {
 					...command,
 					content: {
 						...command.content,
-						headers: { ...command.content.headers, ['Authorization']: `Bearer ${bearerToken.token.access_token}` },
+						headers: { ...command.content.headers, ['Authorization']: bearerHeader },
 					},
 				}
 			}