feat: node-http-handler set default keep-alive to true (#307)

Author: trivikr

packages/node-http-handler/src/node-http-handler.ts

@@ -15,11 +15,18 @@ import { setSocketTimeout } from "./set-socket-timeout";
 import { writeRequestBody } from "./write-request-body";
 
 export class NodeHttpHandler implements HttpHandler<Readable, NodeHttpOptions> {
-  constructor(private readonly httpOptions: NodeHttpOptions = {}) {}
+  private readonly httpAgent: http.Agent;
+  private readonly httpsAgent: https.Agent;
+
+  constructor(private readonly httpOptions: NodeHttpOptions = {}) {
+    const { keepAlive } = httpOptions;
+    this.httpAgent = new http.Agent({ keepAlive });
+    this.httpsAgent = new https.Agent({ keepAlive });
+  }
 
   destroy(): void {
-    // pass for now, but this may destroy the underlying agent in the future
-    // if we decide to enable keep-alive by default.
+    this.httpAgent.destroy();
+    this.httpsAgent.destroy();
   }
 
   handle(
@@ -43,7 +50,8 @@ export class NodeHttpHandler implements HttpHandler<Readable, NodeHttpOptions> {
       host: request.hostname,
       method: request.method,
       path: path,
-      port: request.port
+      port: request.port,
+      agent: isSSL ? this.httpsAgent : this.httpAgent
     };
 
     return new Promise((resolve, reject) => {

packages/types/src/http.ts

@@ -145,13 +145,33 @@ export interface HttpOptions {}
  * Represents the http options that can be passed to a browser http client.
  */
 export interface BrowserHttpOptions extends HttpOptions {
+  /**
+   * The number of milliseconds a request can take before being automatically
+   * terminated.
+   */
   requestTimeout?: number;
 }
 
 /**
  * Represents the http options that can be passed to a node http client.
  */
 export interface NodeHttpOptions extends HttpOptions {
+  /**
+   * The maximum time in milliseconds that the connection phase of a request
+   * may take before the connection attempt is abandoned.
+   */
   connectionTimeout?: number;
+
+  /**
+   * Whether sockets should be kept open even when there are no outstanding
+   * requests so that future requests can forgo having to reestablish a TCP or
+   * TLS connection.
+   */
+  keepAlive?: boolean;
+
+  /**
+   * The maximum time in milliseconds that a socket may remain idle before it
+   * is closed.
+   */
   socketTimeout?: number;
 }