feat: use keep alive agents for all fragment requests

lib/agent-store.js

@@ -0,0 +1,20 @@
+'use strict';
+const Agent = require('agentkeepalive');
+const { SOCKET_TTL } = require('./constants');
+
+class AgentStore {
+    constructor() {
+        const defaultAgentOpts = { socketActiveTTL: SOCKET_TTL };
+        this.httpAgent = new Agent(defaultAgentOpts);
+        this.httpsAgent = new Agent.HttpsAgent(defaultAgentOpts);
+    }
+
+    getAgent(protocol) {
+        if (protocol === 'http:') {
+            return this.httpAgent;
+        }
+        return this.httpsAgent;
+    }
+}
+
+module.exports = new AgentStore();

lib/constants.js

@@ -0,0 +1,10 @@
+'use strict';
+
+/**
+ * Sets the timeout for the socket active time to live even if its in use.
+ */
+const SOCKET_TTL = 60 * 1000;
+
+module.exports = {
+    SOCKET_TTL
+};

lib/request-fragment.js

@@ -4,8 +4,9 @@ const http = require('http');
 const https = require('https');
 const url = require('url');
 const { globalTracer, FORMAT_HTTP_HEADERS } = require('opentracing');
-const tracer = globalTracer();
+const agentStore = require('./agent-store');
 
+const tracer = globalTracer();
 // By default tailor supports gzipped response from fragments
 const requiredHeaders = {
     'accept-encoding': 'gzip, deflate'
@@ -33,6 +34,7 @@ module.exports = filterHeaders => (
         const parsedUrl = url.parse(fragmentUrl);
         const options = Object.assign(
             {
+                agent: agentStore.getAgent(parsedUrl.protocol),
                 headers: Object.assign(
                     filterHeaders(fragmentAttributes, request),
                     requiredHeaders

package.json

@@ -33,6 +33,7 @@
   "author": "Andrey Kuzmin",
   "license": "MIT",
   "dependencies": {
+    "agentkeepalive": "^4.0.0",
     "opentracing": "^0.14.3",
     "parse5": "^3.0.3",
     "util.promisify": "^1.0.0"

tests/agent-store.js

@@ -0,0 +1,18 @@
+'use strict';
+const { parse } = require('url');
+const Agent = require('agentkeepalive');
+const assert = require('assert');
+const agentStore = require('../lib/agent-store');
+
+describe('Agent Store', () => {
+    it('should get https agent by default', () => {
+        const agent = agentStore.getAgent();
+        assert(agent instanceof Agent.HttpsAgent);
+    });
+
+    it('shoulg get http agent for http endpoints', () => {
+        const { protocol } = parse('http://test.com');
+        const agent = agentStore.getAgent(protocol);
+        assert(agent instanceof Agent);
+    });
+});

yarn.lock

@@ -38,6 +38,15 @@ agentkeepalive@^2.0.3:
   version "2.2.0"
   resolved "https://registry.yarnpkg.com/agentkeepalive/-/agentkeepalive-2.2.0.tgz#c5d1bd4b129008f1163f236f86e5faea2026e2ef"
 
+agentkeepalive@^4.0.0:
+  version "4.0.0"
+  resolved "https://registry.yarnpkg.com/agentkeepalive/-/agentkeepalive-4.0.0.tgz#777e7e4c828bde2690cc7a374ede587d45ba4271"
+  integrity sha512-McCjHBAI3FGTy9XOMDr/8qzXK4VBL3h+O/TqlBdsyiwX21SdPCQhPIX0Y1HS5ctO5m2maVQRJWEn0IrzKRB6oQ==
+  dependencies:
+    debug "^4.1.0"
+    depd "^1.1.2"
+    humanize-ms "^1.2.1"
+
 ajv-keywords@^1.0.0:
   version "1.5.1"
   resolved "https://registry.yarnpkg.com/ajv-keywords/-/ajv-keywords-1.5.1.tgz#314dd0a4b3368fad3dfcdc54ede6171b886daf3c"
@@ -423,6 +432,13 @@ debug@^3.1.0:
   dependencies:
     ms "2.0.0"
 
+debug@^4.1.0:
+  version "4.1.1"
+  resolved "https://registry.yarnpkg.com/debug/-/debug-4.1.1.tgz#3b72260255109c6b589cee050f1d516139664791"
+  integrity sha512-pYAIzeRo8J6KPEaJ0VWOh5Pzkbw/RetuzehGM7QRRX5he4fPHx2rdKMB256ehJCkX+XRQm16eZLqLNS8RSZXZw==
+  dependencies:
+    ms "^2.1.1"
+
 decamelize@^1.0.0:
   version "1.2.0"
   resolved "https://registry.yarnpkg.com/decamelize/-/decamelize-1.2.0.tgz#f6534d15148269b20352e7bee26f501f9a191290"
@@ -464,6 +480,11 @@ delayed-stream@~1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/delayed-stream/-/delayed-stream-1.0.0.tgz#df3ae199acadfb7d440aaae0b29e2272b24ec619"
 
+depd@^1.1.2:
+  version "1.1.2"
+  resolved "https://registry.yarnpkg.com/depd/-/depd-1.1.2.tgz#9bcd52e14c097763e749b274c4346ed2e560b5a9"
+  integrity sha1-m81S4UwJd2PnSbJ0xDRu0uVgtak=
+
 [email protected]:
   version "3.2.0"
   resolved "https://registry.yarnpkg.com/diff/-/diff-3.2.0.tgz#c9ce393a4b7cbd0b058a725c93df299027868ff9"
@@ -893,6 +914,13 @@ https-proxy-agent@^2.1.0:
     agent-base "^4.1.0"
     debug "^3.1.0"
 
+humanize-ms@^1.2.1:
+  version "1.2.1"
+  resolved "https://registry.yarnpkg.com/humanize-ms/-/humanize-ms-1.2.1.tgz#c46e3159a293f6b896da29316d8b6fe8bb79bbed"
+  integrity sha1-xG4xWaKT9riW2ikxbYtv6Lt5u+0=
+  dependencies:
+    ms "^2.0.0"
+
 iamdee@^0.4.0:
   version "0.4.0"
   resolved "https://registry.yarnpkg.com/iamdee/-/iamdee-0.4.0.tgz#4c4872db5e82229a361eabad543c160d7f16959d"
@@ -1299,6 +1327,11 @@ [email protected]:
   version "2.0.0"
   resolved "https://registry.yarnpkg.com/ms/-/ms-2.0.0.tgz#5608aeadfc00be6c2901df5f9861788de0d597c8"
 
+ms@^2.0.0, ms@^2.1.1:
+  version "2.1.1"
+  resolved "https://registry.yarnpkg.com/ms/-/ms-2.1.1.tgz#30a5864eb3ebb0a66f2ebe6d727af06a09d86e0a"
+  integrity sha512-tgp+dl5cGk28utYktBsrFqA7HKgrhgPsg6Z/EfhWI4gl1Hwq8B/GmY/0oXZ6nF8hDVesS/FpnYaD/kOWhYQvyg==
+
 [email protected]:
   version "0.0.7"
   resolved "https://registry.yarnpkg.com/mute-stream/-/mute-stream-0.0.7.tgz#3075ce93bc21b8fab43e1bc4da7e8115ed1e7bab"