chore: add support for oauth in public apis

src/auth_strategy/AuthStrategy.ts

@@ -0,0 +1,11 @@
+export default abstract class AuthStrategy {
+  private authType: string;
+  protected constructor(authType: string) {
+    this.authType = authType;
+  }
+  getAuthType(): string {
+    return this.authType;
+  }
+  abstract getAuthString(): Promise<string>;
+  abstract requiresAuthentication(): boolean;
+}

src/auth_strategy/BasicAuthStrategy.ts

@@ -0,0 +1,23 @@
+import AuthStrategy from "./AuthStrategy";
+
+export default class BasicAuthStrategy extends AuthStrategy {
+  private username: string;
+  private password: string;
+
+  constructor(username: string, password: string) {
+    super("basic");
+    this.username = username;
+    this.password = password;
+  }
+
+  getAuthString(): Promise<string> {
+    const auth = Buffer.from(this.username + ":" + this.password).toString(
+      "base64"
+    );
+    return Promise.resolve(`Basic ${auth}`);
+  }
+
+  requiresAuthentication(): boolean {
+    return true;
+  }
+}

src/auth_strategy/NoAuthStrategy.ts

@@ -0,0 +1,15 @@
+import AuthStrategy from "./AuthStrategy";
+
+export default class NoAuthStrategy extends AuthStrategy {
+  constructor() {
+    super("noauth");
+  }
+
+  getAuthString(): Promise<string> {
+    return Promise.resolve("");
+  }
+
+  requiresAuthentication(): boolean {
+    return false;
+  }
+}

src/auth_strategy/TokenAuthStrategy.ts

@@ -0,0 +1,67 @@
+import AuthStrategy from "./AuthStrategy";
+import TokenManager from "../http/bearer_token/TokenManager";
+import jwt, { JwtPayload } from "jsonwebtoken";
+
+export default class TokenAuthStrategy extends AuthStrategy {
+  private token: string;
+  private tokenManager: TokenManager;
+
+  constructor(tokenManager: TokenManager) {
+    super("token");
+    this.token = "";
+    this.tokenManager = tokenManager;
+  }
+
+  async getAuthString(): Promise<string> {
+    return this.fetchToken()
+      .then((token) => {
+        this.token = token;
+        return `Bearer ${this.token}`;
+      })
+      .catch((error) => {
+        throw new Error(`Failed to fetch access token: ${error.message}`);
+      });
+  }
+
+  requiresAuthentication(): boolean {
+    return true;
+  }
+
+  async fetchToken(): Promise<string> {
+    if (
+      this.token == null ||
+      this.token.length === 0 ||
+      this.isTokenExpired(this.token)
+    ) {
+      return this.tokenManager.fetchToken();
+    }
+    return Promise.resolve(this.token);
+  }
+
+  /**
+   * Function to check if the token is expired with a buffer of 30 seconds.
+   * @param token - The JWT token as a string.
+   * @returns Boolean indicating if the token is expired.
+   */
+  isTokenExpired(token: string): boolean {
+    try {
+      // Decode the token without verifying the signature, as we only want to read the expiration for this check
+      const decoded = jwt.decode(token) as JwtPayload;
+
+      if (!decoded || !decoded.exp) {
+        // If the token doesn't have an expiration, consider it expired
+        return true;
+      }
+
+      const expiresAt = decoded.exp * 1000;
+      const bufferMilliseconds = 30 * 1000;
+      const bufferExpiresAt = expiresAt - bufferMilliseconds;
+
+      // Return true if the current time is after the expiration time with buffer
+      return Date.now() > bufferExpiresAt;
+    } catch (error) {
+      // If there's an error decoding the token, consider it expired
+      return true;
+    }
+  }
+}

src/base/BaseTwilio.ts

@@ -1,6 +1,8 @@
 import RequestClient from "./RequestClient"; /* jshint ignore:line */
 import { HttpMethod } from "../interfaces"; /* jshint ignore:line */
 import { Headers } from "../http/request"; /* jshint ignore:line */
+import AuthStrategy from "../auth_strategy/AuthStrategy"; /* jshint ignore:line */
+import CredentialProvider from "../credential_provider/CredentialProvider"; /* jshint ignore:line */
 
 const os = require("os"); /* jshint ignore:line */
 const url = require("url"); /* jshint ignore:line */
@@ -40,6 +42,7 @@ namespace Twilio {
     uri?: string;
     username?: string;
     password?: string;
+    authStrategy?: AuthStrategy;
     headers?: Headers;
     params?: object;
     data?: object;
@@ -56,9 +59,10 @@ namespace Twilio {
   /* jshint ignore:end */
 
   export class Client {
-    username: string;
-    password: string;
+    username?: string;
+    password?: string;
     accountSid: string;
+    credentialProvider?: CredentialProvider;
     opts?: ClientOpts;
     env?: NodeJS.ProcessEnv;
     edge?: string;
@@ -101,23 +105,23 @@ namespace Twilio {
     /* jshint ignore:end */
 
     constructor(username?: string, password?: string, opts?: ClientOpts) {
-      this.opts = opts || {};
-      this.env = this.opts.env || {};
+      this.setOpts(opts);
       this.username =
         username ??
-        this.env.TWILIO_ACCOUNT_SID ??
-        process.env.TWILIO_ACCOUNT_SID ??
-        (() => {
-          throw new Error("username is required");
-        })();
+        this.env?.TWILIO_ACCOUNT_SID ??
+        process.env.TWILIO_ACCOUNT_SID;
       this.password =
         password ??
-        this.env.TWILIO_AUTH_TOKEN ??
-        process.env.TWILIO_AUTH_TOKEN ??
-        (() => {
-          throw new Error("password is required");
-        })();
-      this.accountSid = this.opts.accountSid || this.username;
+        this.env?.TWILIO_AUTH_TOKEN ??
+        process.env.TWILIO_AUTH_TOKEN;
+      this.accountSid = "";
+      this.setAccountSid(this.opts?.accountSid || this.username);
+      this.invalidateOAuth();
+    }
+
+    setOpts(opts?: ClientOpts) {
+      this.opts = opts || {};
+      this.env = this.opts.env || {};
       this.edge =
         this.opts.edge ?? this.env.TWILIO_EDGE ?? process.env.TWILIO_EDGE;
       this.region =
@@ -144,16 +148,35 @@ namespace Twilio {
       if (this.opts.lazyLoading === false) {
         this._httpClient = this.httpClient;
       }
+    }
 
-      if (!this.accountSid.startsWith("AC")) {
-        const apiKeyMsg = this.accountSid.startsWith("SK")
+    setAccountSid(accountSid?: string) {
+      this.accountSid = accountSid || "";
+
+      if (this.accountSid && !this.accountSid?.startsWith("AC")) {
+        const apiKeyMsg = this.accountSid?.startsWith("SK")
           ? ". The given SID indicates an API Key which requires the accountSid to be passed as an additional option"
           : "";
 
         throw new Error("accountSid must start with AC" + apiKeyMsg);
       }
     }
 
+    setCredentialProvider(credentialProvider: CredentialProvider) {
+      this.credentialProvider = credentialProvider;
+      this.accountSid = "";
+      this.invalidateBasicAuth();
+    }
+
+    invalidateBasicAuth() {
+      this.username = undefined;
+      this.password = undefined;
+    }
+
+    invalidateOAuth() {
+      this.credentialProvider = undefined;
+    }
+
     get httpClient() {
       if (!this._httpClient) {
         this._httpClient = new RequestClient({
@@ -196,6 +219,22 @@ namespace Twilio {
 
       const username = opts.username || this.username;
       const password = opts.password || this.password;
+      const authStrategy =
+        opts.authStrategy || this.credentialProvider?.toAuthStrategy();
+
+      if (!authStrategy) {
+        if (!username) {
+          (() => {
+            throw new Error("username is required");
+          })();
+        }
+
+        if (!password) {
+          (() => {
+            throw new Error("password is required");
+          })();
+        }
+      }
 
       const headers = opts.headers || {};
 
@@ -223,7 +262,7 @@ namespace Twilio {
         headers["Content-Type"] = "application/x-www-form-urlencoded";
       }
 
-      if (!headers["Accept"]) {
+      if (opts.method !== "delete" && !headers["Accept"]) {
         headers["Accept"] = "application/json";
       }
 
@@ -235,6 +274,7 @@ namespace Twilio {
         uri: uri.href,
         username: username,
         password: password,
+        authStrategy: authStrategy,
         headers: headers,
         params: opts.params,
         data: opts.data,

src/base/Page.ts

@@ -249,6 +249,8 @@ export default class Page<
     if (keys.length === 1) {
       return payload[keys[0]];
     }
+    for (const key of keys)
+      if (Array.isArray(payload[key])) return payload[key];
 
     throw new Error("Page Records cannot be deserialized");
   }

src/base/RequestClient.ts

@@ -6,9 +6,10 @@ import qs from "qs";
 import * as https from "https";
 import Response from "../http/response";
 import Request, {
-  RequestOptions as LastRequestOptions,
   Headers,
+  RequestOptions as LastRequestOptions,
 } from "../http/request";
+import AuthStrategy from "../auth_strategy/AuthStrategy";
 
 const DEFAULT_CONTENT_TYPE = "application/x-www-form-urlencoded";
 const DEFAULT_TIMEOUT = 30000;
@@ -149,6 +150,7 @@ class RequestClient {
    * @param opts.uri - The request uri
    * @param opts.username - The username used for auth
    * @param opts.password - The password used for auth
+   * @param opts.authStrategy - The authStrategy for API call
    * @param opts.headers - The request headers
    * @param opts.params - The request params
    * @param opts.data - The request data
@@ -157,7 +159,7 @@ class RequestClient {
    * @param opts.forever - Set to true to use the forever-agent
    * @param opts.logLevel - Show debug logs
    */
-  request<TData>(
+  async request<TData>(
     opts: RequestClient.RequestOptions<TData>
   ): Promise<Response<TData>> {
     if (!opts.method) {
@@ -180,6 +182,8 @@ class RequestClient {
         "base64"
       );
       headers.Authorization = "Basic " + auth;
+    } else if (opts.authStrategy) {
+      headers.Authorization = await opts.authStrategy.getAuthString();
     }
 
     const options: AxiosRequestConfig = {
@@ -296,6 +300,10 @@ namespace RequestClient {
      * The password used for auth
      */
     password?: string;
+    /**
+     * The AuthStrategy for API Call
+     */
+    authStrategy?: AuthStrategy;
     /**
      * The request headers
      */

src/credential_provider/ClientCredentialProvider.ts

@@ -0,0 +1,66 @@
+import CredentialProvider from "./CredentialProvider";
+import TokenManager from "../http/bearer_token/TokenManager";
+import AuthStrategy from "../auth_strategy/AuthStrategy";
+import ApiTokenManager from "../http/bearer_token/ApiTokenManager";
+import TokenAuthStrategy from "../auth_strategy/TokenAuthStrategy";
+
+class ClientCredentialProvider extends CredentialProvider {
+  grantType: string;
+  clientId: string;
+  clientSecret: string;
+  tokenManager: TokenManager | null;
+
+  constructor() {
+    super("client-credentials");
+    this.grantType = "client_credentials";
+    this.clientId = "";
+    this.clientSecret = "";
+    this.tokenManager = null;
+  }
+
+  public toAuthStrategy(): AuthStrategy {
+    if (this.tokenManager == null) {
+      this.tokenManager = new ApiTokenManager({
+        grantType: this.grantType,
+        clientId: this.clientId,
+        clientSecret: this.clientSecret,
+      });
+    }
+    return new TokenAuthStrategy(this.tokenManager);
+  }
+}
+
+namespace ClientCredentialProvider {
+  export class ClientCredentialProviderBuilder {
+    private readonly instance: ClientCredentialProvider;
+
+    constructor() {
+      this.instance = new ClientCredentialProvider();
+    }
+
+    public setClientId(clientId: string): ClientCredentialProviderBuilder {
+      this.instance.clientId = clientId;
+      return this;
+    }
+
+    public setClientSecret(
+      clientSecret: string
+    ): ClientCredentialProviderBuilder {
+      this.instance.clientSecret = clientSecret;
+      return this;
+    }
+
+    public setTokenManager(
+      tokenManager: TokenManager
+    ): ClientCredentialProviderBuilder {
+      this.instance.tokenManager = tokenManager;
+      return this;
+    }
+
+    public build(): ClientCredentialProvider {
+      return this.instance;
+    }
+  }
+}
+
+export = ClientCredentialProvider;