Rearrange some code

Author: nirinchev

src/rfc-8252-http-server.spec.ts

@@ -1,4 +1,4 @@
-import { RFC8252HTTPServer } from './rfc-8252-http-server';
+import { getAllInterfaces, RFC8252HTTPServer } from './rfc-8252-http-server';
 import { expect } from 'chai';
 import type { Server as HTTPServer } from 'http';
 import { createServer as createHTTPServer } from 'http';
@@ -487,27 +487,21 @@ describe('RFC8252HTTPServer', function () {
     });
   });
 
-  context('with dns duplicates', function () {
+  context('getAllInterfaces', function () {
     let dnsLookupStub: sinon.SinonStub;
-    const _getAllInterfaces = RFC8252HTTPServer['_getAllInterfaces'];
-
     this.beforeEach(function () {
-      dnsLookupStub = sinon.stub(dns, 'lookup');
-    });
-
-    this.afterEach(function () {
-      sinon.restore();
+      dnsLookupStub = sinon.stub();
     });
 
-    it('only filters exact duplicates', async function () {
+    it('filters out exact duplicates', async function () {
       dnsLookupStub.resolves([
         { address: '127.0.0.1', family: 4 },
         { address: '127.0.0.1', family: 4 },
         { address: '[::1]', family: 6 },
         { address: '[::1]', family: 6 },
       ]);
 
-      const interfaces = await _getAllInterfaces('localhost');
+      const interfaces = await getAllInterfaces('localhost', dnsLookupStub);
 
       expect(interfaces).to.have.lengthOf(2);
       expect(interfaces[0].address).to.equal('127.0.0.1');
@@ -522,7 +516,7 @@ describe('RFC8252HTTPServer', function () {
         { address: '127.0.0.1', family: 6 },
       ]);
 
-      const interfaces = await _getAllInterfaces('localhost');
+      const interfaces = await getAllInterfaces('localhost', dnsLookupStub);
 
       expect(interfaces).to.have.lengthOf(2);
       expect(interfaces[0].address).to.equal('127.0.0.1');
@@ -537,7 +531,7 @@ describe('RFC8252HTTPServer', function () {
         { address: '192.168.1.15', family: 4 },
       ]);
 
-      const interfaces = await _getAllInterfaces('localhost');
+      const interfaces = await getAllInterfaces('localhost', dnsLookupStub);
 
       expect(interfaces).to.have.lengthOf(2);
       expect(interfaces[0].address).to.equal('127.0.0.1');

src/rfc-8252-http-server.ts

@@ -29,6 +29,26 @@ export interface RFC8252HTTPServerOptions {
   redirectServerRequestHandler?: RedirectServerRequestHandler;
 }
 
+export async function getAllInterfaces(
+  hostname: string,
+  lookup: typeof dns.lookup = dns.lookup
+): Promise<{ address: string; family: number }[]> {
+  const dnsResults = await lookup(hostname, {
+    all: true,
+    hints: ADDRCONFIG,
+  });
+
+  return dnsResults
+    .filter(
+      (dns, index, arr) =>
+        arr.findIndex(
+          (otherDns) =>
+            dns.address === otherDns.address && dns.family === otherDns.family
+        ) === index
+    )
+    .map(({ address, family }) => ({ address, family }));
+}
+
 /** @internal */
 export class RFC8252HTTPServer {
   private readonly redirectUrl: URL;
@@ -272,25 +292,6 @@ export class RFC8252HTTPServer {
     });
   };
 
-  private static async _getAllInterfaces(
-    hostname: string
-  ): Promise<{ address: string; family: number }[]> {
-    const dnsResults = await dns.lookup(hostname, {
-      all: true,
-      hints: ADDRCONFIG,
-    });
-
-    return dnsResults
-      .filter(
-        (dns, index, arr) =>
-          arr.findIndex(
-            (otherDns) =>
-              dns.address === otherDns.address && dns.family === otherDns.family
-          ) === index
-      )
-      .map(({ address, family }) => ({ address, family }));
-  }
-
   /**
    * Add a redirect from a local URL served on the server to an external URL.
    */
@@ -391,7 +392,7 @@ export class RFC8252HTTPServer {
       hostname = hostname.slice(1, -1);
     }
 
-    const dnsResults = await RFC8252HTTPServer._getAllInterfaces(hostname);
+    const dnsResults = await getAllInterfaces(hostname);
 
     this.logger.emit('mongodb-oidc-plugin:local-listen-resolved-hostname', {
       url: this.redirectUrl.toString(),