grpc-js: Use an object to represent subchannel addresses

packages/grpc-js/src/channel.ts

@@ -38,6 +38,7 @@ import { getDefaultAuthority } from './resolver';
 import { LoadBalancingConfig } from './load-balancing-config';
 import { ServiceConfig, validateServiceConfig } from './service-config';
 import { trace } from './logging';
+import { SubchannelAddress } from './subchannel';
 
 export enum ConnectivityState {
   CONNECTING,
@@ -145,7 +146,7 @@ export class ChannelImplementation implements Channel {
     this.subchannelPool = getSubchannelPool((options['grpc.use_local_subchannel_pool'] ?? 0) === 0);
     const channelControlHelper: ChannelControlHelper = {
       createSubchannel: (
-        subchannelAddress: string,
+        subchannelAddress: SubchannelAddress,
         subchannelArgs: ChannelOptions
       ) => {
         return this.subchannelPool.getOrCreateSubchannel(

packages/grpc-js/src/load-balancer-pick-first.ts

@@ -30,7 +30,7 @@ import {
   UnavailablePicker,
 } from './picker';
 import { LoadBalancingConfig } from './load-balancing-config';
-import { Subchannel, ConnectivityStateListener } from './subchannel';
+import { Subchannel, ConnectivityStateListener, SubchannelAddress } from './subchannel';
 import * as logging from './logging';
 import { LogVerbosity } from './constants';
 
@@ -76,7 +76,7 @@ export class PickFirstLoadBalancer implements LoadBalancer {
   /**
    * The list of backend addresses most recently passed to `updateAddressList`.
    */
-  private latestAddressList: string[] = [];
+  private latestAddressList: SubchannelAddress[] = [];
   /**
    * The list of subchannels this load balancer is currently attempting to
    * connect to.
@@ -369,7 +369,7 @@ export class PickFirstLoadBalancer implements LoadBalancer {
   }
 
   updateAddressList(
-    addressList: string[],
+    addressList: SubchannelAddress[],
     lbConfig: LoadBalancingConfig | null
   ): void {
     // lbConfig has no useful information for pick first load balancing

packages/grpc-js/src/load-balancer-round-robin.ts

@@ -30,7 +30,7 @@ import {
   UnavailablePicker,
 } from './picker';
 import { LoadBalancingConfig } from './load-balancing-config';
-import { Subchannel, ConnectivityStateListener } from './subchannel';
+import { Subchannel, ConnectivityStateListener, SubchannelAddress } from './subchannel';
 
 const TYPE_NAME = 'round_robin';
 
@@ -168,7 +168,7 @@ export class RoundRobinLoadBalancer implements LoadBalancer {
   }
 
   updateAddressList(
-    addressList: string[],
+    addressList: SubchannelAddress[],
     lbConfig: LoadBalancingConfig | null
   ): void {
     this.resetSubchannelList();

packages/grpc-js/src/load-balancer.ts

@@ -16,7 +16,7 @@
  */
 
 import { ChannelOptions } from './channel-options';
-import { Subchannel } from './subchannel';
+import { Subchannel, SubchannelAddress } from './subchannel';
 import { ConnectivityState } from './channel';
 import { Picker } from './picker';
 import { LoadBalancingConfig } from './load-balancing-config';
@@ -34,7 +34,7 @@ export interface ChannelControlHelper {
    * @param subchannelArgs Extra channel arguments specified by the load balancer
    */
   createSubchannel(
-    subchannelAddress: string,
+    subchannelAddress: SubchannelAddress,
     subchannelArgs: ChannelOptions
   ): Subchannel;
   /**
@@ -66,7 +66,7 @@ export interface LoadBalancer {
    *     if one was provided
    */
   updateAddressList(
-    addressList: string[],
+    addressList: SubchannelAddress[],
     lbConfig: LoadBalancingConfig | null
   ): void;
   /**

packages/grpc-js/src/resolver-dns.ts

@@ -30,6 +30,7 @@ import { StatusObject } from './call-stream';
 import { Metadata } from './metadata';
 import * as logging from './logging';
 import { LogVerbosity } from './constants';
+import { SubchannelAddress } from './subchannel';
 
 const TRACER_NAME = 'dns_resolver';
 
@@ -112,7 +113,7 @@ const dnsLookupPromise = util.promisify(dns.lookup);
  * @param target
  * @return An "IP:port" string in an array if parsing was successful, `null` otherwise
  */
-function parseIP(target: string): string[] | null {
+function parseIP(target: string): SubchannelAddress[] | null {
   /* These three regular expressions are all mutually exclusive, so we just
    * want the first one that matches the target string, if any do. */
   const ipv4Match = IPV4_REGEX.exec(target);
@@ -123,14 +124,14 @@ function parseIP(target: string): string[] | null {
   }
 
   // ipv6 addresses should be bracketed
-  const addr = ipv4Match ? match[1] : `[${match[1]}]`;
+  const addr = match[1];
   let port: string;
   if (match[2]) {
     port = match[2];
   } else {
     port = DEFAULT_PORT;
   }
-  return [`${addr}:${port}`];
+  return [{host: addr, port: +port}];
 }
 
 /**
@@ -161,7 +162,7 @@ function mergeArrays<T>(...arrays: T[][]): T[] {
  * Resolver implementation that handles DNS names and IP addresses.
  */
 class DnsResolver implements Resolver {
-  private readonly ipResult: string[] | null;
+  private readonly ipResult: SubchannelAddress[] | null;
   private readonly dnsHostname: string | null;
   private readonly port: string | null;
   /* The promise results here contain, in order, the A record, the AAAA record,
@@ -222,23 +223,21 @@ class DnsResolver implements Resolver {
       this.pendingResultPromise.then(
         ([addressList, txtRecord]) => {
           this.pendingResultPromise = null;
-          const ip4Addresses: string[] = addressList
+          const ip4Addresses: dns.LookupAddress[] = addressList
-            .filter(addr => addr.family === 4)
+            .filter(addr => addr.family === 4);
-            .map(addr => `${addr.address}:${this.port}`);
+          let ip6Addresses: dns.LookupAddress[];
-          let ip6Addresses: string[];
           if (semver.satisfies(process.version, IPV6_SUPPORT_RANGE)) {
-            ip6Addresses = addressList
+            ip6Addresses = addressList.filter(addr => addr.family === 6);
-              .filter(addr => addr.family === 6)
-              .map(addr => `[${addr.address}]:${this.port}`);
           } else {
             ip6Addresses = [];
           }
-          const allAddresses: string[] = mergeArrays(
+          const allAddresses: SubchannelAddress[] = mergeArrays(
             ip4Addresses,
             ip6Addresses
-          );
+          ).map(addr => {return {host: addr.address, port: +this.port!};});
+          const allAddressesString: string = '[' + allAddresses.map(addr => addr.host + ':' + addr.port).join(',') + ']';
           trace(
-            'Resolved addresses for target ' + this.target + ': ' + allAddresses
+            'Resolved addresses for target ' + this.target + ': ' + allAddressesString
           );
           if (allAddresses.length === 0) {
             this.listener.onError(this.defaultResolutionError);

packages/grpc-js/src/resolver-uds.ts

@@ -20,6 +20,7 @@ import {
   registerResolver,
   registerDefaultResolver,
 } from './resolver';
+import { SubchannelAddress } from './subchannel';
 
 function getUdsName(target: string): string {
   /* Due to how this resolver is registered, it should only be constructed
@@ -34,9 +35,9 @@ function getUdsName(target: string): string {
 }
 
 class UdsResolver implements Resolver {
-  private addresses: string[] = [];
+  private addresses: SubchannelAddress[] = [];
   constructor(target: string, private listener: ResolverListener) {
-    this.addresses = [getUdsName(target)];
+    this.addresses = [{path: getUdsName(target)}];
   }
   updateResolution(): void {
     process.nextTick(

packages/grpc-js/src/resolver.ts

@@ -20,6 +20,7 @@ import { ServiceConfig } from './service-config';
 import * as resolver_dns from './resolver-dns';
 import * as resolver_uds from './resolver-uds';
 import { StatusObject } from './call-stream';
+import { SubchannelAddress } from './subchannel';
 
 /**
  * A listener object passed to the resolver's constructor that provides name
@@ -36,7 +37,7 @@ export interface ResolverListener {
    *     service configuration was invalid
    */
   onSuccessfulResolution(
-    addressList: string[],
+    addressList: SubchannelAddress[],
     serviceConfig: ServiceConfig | null,
     serviceConfigError: StatusObject | null
   ): void;

packages/grpc-js/src/resolving-load-balancer.ts

@@ -34,6 +34,7 @@ import { StatusObject } from './call-stream';
 import { Metadata } from './metadata';
 import * as logging from './logging';
 import { LogVerbosity } from './constants';
+import { SubchannelAddress } from './subchannel';
 
 const TRACER_NAME = 'resolving_load_balancer';
 
@@ -132,7 +133,7 @@ export class ResolvingLoadBalancer implements LoadBalancer {
     this.updateState(ConnectivityState.IDLE, new QueuePicker(this));
     this.innerResolver = createResolver(target, {
       onSuccessfulResolution: (
-        addressList: string[],
+        addressList: SubchannelAddress[],
         serviceConfig: ServiceConfig | null,
         serviceConfigError: ServiceError | null
       ) => {
@@ -243,7 +244,7 @@ export class ResolvingLoadBalancer implements LoadBalancer {
 
     this.innerChannelControlHelper = {
       createSubchannel: (
-        subchannelAddress: string,
+        subchannelAddress: SubchannelAddress,
         subchannelArgs: ChannelOptions
       ) => {
         return this.channelControlHelper.createSubchannel(
@@ -289,7 +290,7 @@ export class ResolvingLoadBalancer implements LoadBalancer {
 
     this.replacementChannelControlHelper = {
       createSubchannel: (
-        subchannelAddress: string,
+        subchannelAddress: SubchannelAddress,
         subchannelArgs: ChannelOptions
       ) => {
         return this.channelControlHelper.createSubchannel(
@@ -409,7 +410,7 @@ export class ResolvingLoadBalancer implements LoadBalancer {
   }
 
   updateAddressList(
-    addressList: string[],
+    addressList: SubchannelAddress[],
     lbConfig: LoadBalancingConfig | null
   ) {
     throw new Error('updateAddressList not supported on ResolvingLoadBalancer');

packages/grpc-js/src/subchannel-pool.ts

@@ -16,7 +16,7 @@
  */
 
 import { ChannelOptions, channelOptionsEqual } from './channel-options';
-import { Subchannel } from './subchannel';
+import { Subchannel, SubchannelAddress, subchannelAddressEqual } from './subchannel';
 import { ChannelCredentials } from './channel-credentials';
 
 // 10 seconds in milliseconds. This value is arbitrary.
@@ -28,13 +28,12 @@ const REF_CHECK_INTERVAL = 10_000;
 
 export class SubchannelPool {
   private pool: {
-    [channelTarget: string]: {
+    [channelTarget: string]: Array<{
-      [subchannelTarget: string]: Array<{
+      subchannelAddress: SubchannelAddress;
       channelArguments: ChannelOptions;
       channelCredentials: ChannelCredentials;
       subchannel: Subchannel;
     }>;
-    };
   } = Object.create(null);
 
   /**
@@ -62,9 +61,7 @@ export class SubchannelPool {
      * do not need to be filtered */
     // tslint:disable-next-line:forin
     for (const channelTarget in this.pool) {
-      // tslint:disable-next-line:forin
+      const subchannelObjArray = this.pool[channelTarget];
-      for (const subchannelTarget in this.pool[channelTarget]) {
-        const subchannelObjArray = this.pool[channelTarget][subchannelTarget];
 
       const refedSubchannels = subchannelObjArray.filter(
         value => !value.subchannel.unrefIfOneRef()
@@ -77,8 +74,7 @@ export class SubchannelPool {
       /* For each subchannel in the pool, try to unref it if it has
         * exactly one ref (which is the ref from the pool itself). If that
         * does happen, remove the subchannel from the pool */
-        this.pool[channelTarget][subchannelTarget] = refedSubchannels;
+      this.pool[channelTarget] = refedSubchannels;
-      }
     }
     /* Currently we do not delete keys with empty values. If that results
      * in significant memory usage we should change it. */
@@ -114,17 +110,17 @@ export class SubchannelPool {
    */
   getOrCreateSubchannel(
     channelTarget: string,
-    subchannelTarget: string,
+    subchannelTarget: SubchannelAddress,
     channelArguments: ChannelOptions,
     channelCredentials: ChannelCredentials
   ): Subchannel {
     this.ensureCleanupTask();
 
     if (channelTarget in this.pool) {
-      if (subchannelTarget in this.pool[channelTarget]) {
+      const subchannelObjArray = this.pool[channelTarget];
-        const subchannelObjArray = this.pool[channelTarget][subchannelTarget];
       for (const subchannelObj of subchannelObjArray) {
         if (
+          subchannelAddressEqual(subchannelTarget, subchannelObj.subchannelAddress) &&
           channelOptionsEqual(
             channelArguments,
             subchannelObj.channelArguments
@@ -135,7 +131,6 @@ export class SubchannelPool {
         }
       }
     }
-    }
     // If we get here, no matching subchannel was found
     const subchannel = new Subchannel(
       channelTarget,
@@ -144,12 +139,10 @@ export class SubchannelPool {
       channelCredentials
     );
     if (!(channelTarget in this.pool)) {
-      this.pool[channelTarget] = Object.create(null);
+      this.pool[channelTarget] = [];
     }
-    if (!(subchannelTarget in this.pool[channelTarget])) {
+    this.pool[channelTarget].push({
-      this.pool[channelTarget][subchannelTarget] = [];
+      subchannelAddress: subchannelTarget,
-    }
-    this.pool[channelTarget][subchannelTarget].push({
       channelArguments,
       channelCredentials,
       subchannel,

packages/grpc-js/src/subchannel.ts

@@ -20,12 +20,13 @@ import { ChannelCredentials } from './channel-credentials';
 import { Metadata } from './metadata';
 import { Http2CallStream } from './call-stream';
 import { ChannelOptions } from './channel-options';
-import { PeerCertificate, checkServerIdentity } from 'tls';
+import { PeerCertificate, checkServerIdentity, TLSSocket } from 'tls';
 import { ConnectivityState } from './channel';
 import { BackoffTimeout, BackoffOptions } from './backoff-timeout';
 import { getDefaultAuthority } from './resolver';
 import * as logging from './logging';
 import { LogVerbosity } from './constants';
+import { SocketConnectOpts } from 'net';
 
 const { version: clientVersion } = require('../../package.json');
 
@@ -73,6 +74,22 @@ function uniformRandom(min: number, max: number) {
 
 const tooManyPingsData: Buffer = Buffer.from('too_many_pings', 'ascii');
 
+/**
+ * This represents a single backend address to connect to. This interface is a
+ * subset of net.SocketConnectOpts, i.e. the options described at
+ * https://nodejs.org/api/net.html#net_socket_connect_options_connectlistener.
+ * Those are in turn a subset of the options that can be passed to http2.connect.
+ */
+export interface SubchannelAddress {
+  port?: number;
+  host?: string;
+  path?: string;
+}
+
+export function subchannelAddressEqual(address1: SubchannelAddress, address2: SubchannelAddress) : boolean {
+  return address1.port === address2.port && address1.host === address2.host && address1.path === address2.path;
+}
+
 export class Subchannel {
   /**
    * The subchannel's current connectivity state. Invariant: `session` === `null`
@@ -135,6 +152,11 @@ export class Subchannel {
    */
   private refcount = 0;
 
+  /**
+   * A string representation of the subchannel address, for logging/tracing
+   */
+  private subchannelAddressString: string;
+
   /**
    * A class representing a connection to a single backend.
    * @param channelTarget The target string for the channel as a whole
@@ -147,7 +169,7 @@ export class Subchannel {
    */
   constructor(
     private channelTarget: string,
-    private subchannelAddress: string,
+    private subchannelAddress: SubchannelAddress,
     private options: ChannelOptions,
     private credentials: ChannelCredentials
   ) {
@@ -187,6 +209,11 @@ export class Subchannel {
         );
       }
     }, backoffOptions);
+    if (subchannelAddress.host || subchannelAddress.port) {
+      this.subchannelAddressString = `${subchannelAddress.host}:${subchannelAddress.port}`;
+    } else {
+      this.subchannelAddressString = `${subchannelAddress.path}`;
+    }
   }
 
   /**
@@ -225,10 +252,11 @@ export class Subchannel {
   }
 
   private startConnectingInternal() {
-    const connectionOptions: http2.SecureClientSessionOptions =
+    let connectionOptions: http2.SecureClientSessionOptions =
       this.credentials._getConnectionOptions() || {};
     let addressScheme = 'http://';
     if ('secureContext' in connectionOptions) {
+      connectionOptions.protocol = 'https:';
       addressScheme = 'https://';
       // If provided, the value of grpc.ssl_target_name_override should be used
       // to override the target hostname when checking server identity.
@@ -248,8 +276,21 @@ export class Subchannel {
         connectionOptions.servername = getDefaultAuthority(this.channelTarget);
       }
     }
+    connectionOptions = Object.assign(connectionOptions, this.subchannelAddress);
+    /* http2.connect uses the options here:
+     * https://github.com/nodejs/node/blob/70c32a6d190e2b5d7b9ff9d5b6a459d14e8b7d59/lib/internal/http2/core.js#L3028-L3036
+     * The spread operator overides earlier values with later ones, so any port
+     * or host values in the options will be used rather than any values extracted
+     * from the first argument. In addition, the path overrides the host and port,
+     * as documented for plaintext connections here:
+     * https://nodejs.org/api/net.html#net_socket_connect_options_connectlistener
+     * and for TLS connections here:
+     * https://nodejs.org/api/tls.html#tls_tls_connect_options_callback.
+     * The first argument just needs to be parseable as a URL and the scheme
+     * determines whether the connection will be established over TLS or not.
+     */
     const session = http2.connect(
-      addressScheme + this.subchannelAddress,
+      addressScheme + getDefaultAuthority(this.channelTarget),
       connectionOptions
     );
     this.session = session;
@@ -328,7 +369,7 @@ export class Subchannel {
       return false;
     }
     trace(
-      this.subchannelAddress +
+      this.subchannelAddressString +
         ' ' +
         ConnectivityState[this.connectivityState] +
         ' -> ' +
@@ -400,7 +441,7 @@ export class Subchannel {
 
   callRef() {
     trace(
-      this.subchannelAddress +
+      this.subchannelAddressString +
         ' callRefcount ' +
         this.callRefcount +
         ' -> ' +
@@ -417,7 +458,7 @@ export class Subchannel {
 
   callUnref() {
     trace(
-      this.subchannelAddress +
+      this.subchannelAddressString +
         ' callRefcount ' +
         this.callRefcount +
         ' -> ' +
@@ -435,7 +476,7 @@ export class Subchannel {
 
   ref() {
     trace(
-      this.subchannelAddress +
+      this.subchannelAddressString +
         ' callRefcount ' +
         this.refcount +
         ' -> ' +
@@ -446,7 +487,7 @@ export class Subchannel {
 
   unref() {
     trace(
-      this.subchannelAddress +
+      this.subchannelAddressString +
         ' callRefcount ' +
         this.refcount +
         ' -> ' +
@@ -557,6 +598,6 @@ export class Subchannel {
   }
 
   getAddress(): string {
-    return this.subchannelAddress;
+    return this.subchannelAddressString;
   }
 }

packages/grpc-js/test/test-resolver.ts

@@ -21,6 +21,7 @@ import * as assert from 'assert';
 import * as resolverManager from '../src/resolver';
 import { ServiceConfig } from '../src/service-config';
 import { StatusObject } from '../src/call-stream';
+import { SubchannelAddress } from '../src/subchannel';
 
 describe('Name Resolver', () => {
   describe('DNS Names', function() {
@@ -33,11 +34,11 @@ describe('Name Resolver', () => {
       const target = 'localhost:50051';
       const listener: resolverManager.ResolverListener = {
         onSuccessfulResolution: (
-          addressList: string[],
+          addressList: SubchannelAddress[],
           serviceConfig: ServiceConfig | null,
           serviceConfigError: StatusObject | null
         ) => {
-          assert(addressList.includes('127.0.0.1:50051'));
+          assert(addressList.some(addr => addr.host === '127.0.0.1' && addr.port === 50051));
           // We would check for the IPv6 address but it needs to be omitted on some Node versions
           done();
         },
@@ -52,11 +53,11 @@ describe('Name Resolver', () => {
       const target = 'localhost';
       const listener: resolverManager.ResolverListener = {
         onSuccessfulResolution: (
-          addressList: string[],
+          addressList: SubchannelAddress[],
           serviceConfig: ServiceConfig | null,
           serviceConfigError: StatusObject | null
         ) => {
-          assert(addressList.includes('127.0.0.1:443'));
+          assert(addressList.some(addr => addr.host === '127.0.0.1' && addr.port === 443));
           // We would check for the IPv6 address but it needs to be omitted on some Node versions
           done();
         },
@@ -71,11 +72,11 @@ describe('Name Resolver', () => {
       const target = '1.2.3.4';
       const listener: resolverManager.ResolverListener = {
         onSuccessfulResolution: (
-          addressList: string[],
+          addressList: SubchannelAddress[],
           serviceConfig: ServiceConfig | null,
           serviceConfigError: StatusObject | null
         ) => {
-          assert(addressList.includes('1.2.3.4:443'));
+          assert(addressList.some(addr => addr.host === '1.2.3.4' && addr.port === 443));
           // We would check for the IPv6 address but it needs to be omitted on some Node versions
           done();
         },
@@ -90,11 +91,11 @@ describe('Name Resolver', () => {
       const target = '::1';
       const listener: resolverManager.ResolverListener = {
         onSuccessfulResolution: (
-          addressList: string[],
+          addressList: SubchannelAddress[],
           serviceConfig: ServiceConfig | null,
           serviceConfigError: StatusObject | null
         ) => {
-          assert(addressList.includes('[::1]:443'));
+          assert(addressList.some(addr => addr.host === '::1' && addr.port === 443));
           // We would check for the IPv6 address but it needs to be omitted on some Node versions
           done();
         },
@@ -109,11 +110,11 @@ describe('Name Resolver', () => {
       const target = '[::1]:50051';
       const listener: resolverManager.ResolverListener = {
         onSuccessfulResolution: (
-          addressList: string[],
+          addressList: SubchannelAddress[],
           serviceConfig: ServiceConfig | null,
           serviceConfigError: StatusObject | null
         ) => {
-          assert(addressList.includes('[::1]:50051'));
+          assert(addressList.some(addr => addr.host === '::1' && addr.port === 50051));
           // We would check for the IPv6 address but it needs to be omitted on some Node versions
           done();
         },
@@ -128,7 +129,7 @@ describe('Name Resolver', () => {
       const target = 'example.com';
       const listener: resolverManager.ResolverListener = {
         onSuccessfulResolution: (
-          addressList: string[],
+          addressList: SubchannelAddress[],
           serviceConfig: ServiceConfig | null,
           serviceConfigError: StatusObject | null
         ) => {
@@ -146,7 +147,7 @@ describe('Name Resolver', () => {
       const target = 'loopback4.unittest.grpc.io';
       const listener: resolverManager.ResolverListener = {
         onSuccessfulResolution: (
-          addressList: string[],
+          addressList: SubchannelAddress[],
           serviceConfig: ServiceConfig | null,
           serviceConfigError: StatusObject | null
         ) => {
@@ -166,7 +167,7 @@ describe('Name Resolver', () => {
       const target = 'network-tools.com';
       const listener: resolverManager.ResolverListener = {
         onSuccessfulResolution: (
-          addressList: string[],
+          addressList: SubchannelAddress[],
           serviceConfig: ServiceConfig | null,
           serviceConfigError: StatusObject | null
         ) => {
@@ -196,7 +197,7 @@ describe('Name Resolver', () => {
       const target2 = 'grpc-test4.sandbox.googleapis.com';
       const listener: resolverManager.ResolverListener = {
         onSuccessfulResolution: (
-          addressList: string[],
+          addressList: SubchannelAddress[],
           serviceConfig: ServiceConfig | null,
           serviceConfigError: StatusObject | null
         ) => {
@@ -218,11 +219,11 @@ describe('Name Resolver', () => {
       const target = 'unix:socket';
       const listener: resolverManager.ResolverListener = {
         onSuccessfulResolution: (
-          addressList: string[],
+          addressList: SubchannelAddress[],
           serviceConfig: ServiceConfig | null,
           serviceConfigError: StatusObject | null
         ) => {
-          assert(addressList.includes('socket'));
+          assert(addressList.some(addr => addr.path = 'socket'));
           done();
         },
         onError: (error: StatusObject) => {
@@ -236,11 +237,11 @@ describe('Name Resolver', () => {
       const target = 'unix:///tmp/socket';
       const listener: resolverManager.ResolverListener = {
         onSuccessfulResolution: (
-          addressList: string[],
+          addressList: SubchannelAddress[],
           serviceConfig: ServiceConfig | null,
           serviceConfigError: StatusObject | null
         ) => {
-          assert(addressList.includes('/tmp/socket'));
+          assert(addressList.some(addr => addr.path = '/tmp/socket'));
           done();
         },
         onError: (error: StatusObject) => {