SWIFT-1308 Run initial DNS seedlist discovery load balancer tests (#671)

Author: kmahar

Sources/TestsCommon/CommonTestUtils.swift

@@ -58,7 +58,7 @@ open class MongoSwiftTestCase: XCTestCase {
             return try! ConnectionString(uri)
         case (.loadBalanced, false):
             guard let uri = Self.multipleMongosLoadBalancedURI else {
-                fatalError("Missing MULTIPLE_MONGOS_LB_URI environment variable")
+                fatalError("Missing MULTI_MONGOS_LB_URI environment variable")
             }
             return try! ConnectionString(uri)
         default:

Tests/LinuxMain.swift

@@ -92,7 +92,8 @@ extension CrudTests {
 
 extension DNSSeedlistTests {
     static var allTests = [
-        ("testInitialDNSSeedlistDiscovery", testInitialDNSSeedlistDiscovery),
+        ("testInitialDNSSeedlistDiscoveryReplicaSet", testInitialDNSSeedlistDiscoveryReplicaSet),
+        ("testInitialDNSSeedlistDiscoveryLoadBalanced", testInitialDNSSeedlistDiscoveryLoadBalanced),
     ]
 }
 

Tests/MongoSwiftTests/DNSSeedlistTests.swift

@@ -46,26 +46,46 @@ final class DNSSeedlistTests: MongoSwiftTestCase {
 
     // Note: the file txt-record-with-overridden-uri-option.json causes a mongoc warning. This is expected.
     // swiftlint:disable:next cyclomatic_complexity
-    func testInitialDNSSeedlistDiscovery() throws {
+    func testInitialDNSSeedlistDiscoveryReplicaSet() throws {
         guard MongoSwiftTestCase.topologyType == .replicaSetWithPrimary else {
             print("Skipping test because of unsupported topology type \(MongoSwiftTestCase.topologyType)")
             return
         }
 
         let tests = try retrieveSpecTestFiles(
             specName: "initial-dns-seedlist-discovery",
+            subdirectory: "replica-set",
             asType: DNSSeedlistTestCase.self
         )
-        for (fileName, testCase) in tests {
-            // TODO: SWIFT-910: unskip this test
-            guard fileName != "txt-record-with-overridden-uri-option.json" else {
-                print("Skipping test file \(fileName); see SWIFT-910")
-                continue
-            }
 
+        try runDNSSeedlistTests(tests)
+    }
+
+    func testInitialDNSSeedlistDiscoveryLoadBalanced() throws {
+        guard MongoSwiftTestCase.topologyType == .loadBalanced else {
+            print("Skipping test because of unsupported topology type \(MongoSwiftTestCase.topologyType)")
+            return
+        }
+
+        let tests = try retrieveSpecTestFiles(
+            specName: "initial-dns-seedlist-discovery",
+            subdirectory: "load-balanced",
+            asType: DNSSeedlistTestCase.self
+        )
+
+        try runDNSSeedlistTests(tests)
+    }
+
+    func runDNSSeedlistTests(_ tests: [(String, DNSSeedlistTestCase)]) throws {
+        for (fileName, testCase) in tests {
             // this particular test case requires SSL is disabled. see DRIVERS-1324.
             let requiresTLS = fileName != "txt-record-with-overridden-ssl-option.json"
 
+            // skipping due to a libmongoc bug. TODO: SWIFT-1343 unskip.
+            guard fileName != "loadBalanced-replicaSet-errors.json" else {
+                continue
+            }
+
             // TLS requirement for this test case is not met.
             guard (requiresTLS && MongoSwiftTestCase.ssl) || (!requiresTLS && !MongoSwiftTestCase.ssl) else {
                 print("Skipping test file \(fileName); TLS requirement not met")

Tests/Specs/initial-dns-seedlist-discovery/tests/README.rst

@@ -8,9 +8,13 @@ to prove their conformance to the Initial DNS Seedlist Discovery spec.
 Test Setup
 ----------
 
-Start a three-node replica set on localhost, on ports 27017, 27018, and 27019,
-with replica set name "repl0". The replica set MUST be started with SSL
-enabled.
+The tests in the ``replica-set`` directory MUST be executed against a
+three-node replica set on localhost ports 27017, 27018, and 27019 with
+replica set name ``repl0``. The tests in ``load-balanced`` MUST be executed
+against a load-balanced sharded cluster with the mongos servers running on
+localhost ports 27017 and 27018 and load balancers, shard servers, and config
+servers running on any open ports. In both cases, the clusters MUST be
+started with SSL enabled.
 
 To run the tests that accompany this spec, you need to configure the SRV and
 TXT records with a real name server. The following records are required for
@@ -41,6 +45,8 @@ these tests::
   _mongodb._tcp.test18.test.build.10gen.cc. 86400  IN SRV  27017  localhost.sub.test.build.10gen.cc.
   _mongodb._tcp.test19.test.build.10gen.cc. 86400  IN SRV  27017  localhost.evil.build.10gen.cc.
   _mongodb._tcp.test19.test.build.10gen.cc. 86400  IN SRV  27017  localhost.test.build.10gen.cc.
+  _mongodb._tcp.test20.test.build.10gen.cc. 86400  IN SRV  27017  localhost.test.build.10gen.cc.
+  _mongodb._tcp.test21.test.build.10gen.cc. 86400  IN SRV  27017  localhost.test.build.10gen.cc.
 
   Record                                    TTL    Class   Text
   test5.test.build.10gen.cc.                86400  IN TXT  "replicaSet=repl0&authSource=thisDB"
@@ -50,6 +56,8 @@ these tests::
   test8.test.build.10gen.cc.                86400  IN TXT  "authSource"
   test10.test.build.10gen.cc.               86400  IN TXT  "socketTimeoutMS=500"
   test11.test.build.10gen.cc.               86400  IN TXT  "replicaS" "et=rep" "l0"
+  test20.test.build.10gen.cc.               86400  IN TXT  "loadBalanced=true"
+  test21.test.build.10gen.cc.               86400  IN TXT  "loadBalanced=false"
 
 Note that ``test4`` is omitted deliberately to test what happens with no SRV
 record. ``test9`` is missing because it was deleted during the development of

Tests/Specs/initial-dns-seedlist-discovery/tests/load-balanced/loadBalanced-directConnection.json

@@ -0,0 +1,14 @@
+{
+  "uri": "mongodb+srv://test20.test.build.10gen.cc/?directConnection=false",
+  "seeds": [
+    "localhost.test.build.10gen.cc:27017"
+  ],
+  "hosts": [
+    "localhost.test.build.10gen.cc:27017"
+  ],
+  "options": {
+    "loadBalanced": true,
+    "ssl": true,
+    "directConnection": false
+  }
+}

Tests/Specs/initial-dns-seedlist-discovery/tests/load-balanced/loadBalanced-no-results.json

@@ -0,0 +1,7 @@
+{
+  "uri": "mongodb+srv://test4.test.build.10gen.cc/?loadBalanced=true",
+  "seeds": [],
+  "hosts": [],
+  "error": true,
+  "comment": "Should fail because no SRV records are present for this URI."
+}

Tests/Specs/initial-dns-seedlist-discovery/tests/load-balanced/loadBalanced-replicaSet-errors.json

@@ -0,0 +1,7 @@
+{
+  "uri": "mongodb+srv://test20.test.build.10gen.cc/?replicaSet=replset",
+  "seeds": [],
+  "hosts": [],
+  "error": true,
+  "comment": "Should fail because loadBalanced=true is incompatible with replicaSet"
+}

Tests/Specs/initial-dns-seedlist-discovery/tests/load-balanced/loadBalanced-true-multiple-hosts.json

@@ -0,0 +1,7 @@
+{
+  "uri": "mongodb+srv://test1.test.build.10gen.cc/?loadBalanced=true",
+  "seeds": [],
+  "hosts": [],
+  "error": true,
+  "comment": "Should fail because loadBalanced is true but the SRV record resolves to multiple hosts"
+}

Tests/Specs/initial-dns-seedlist-discovery/tests/load-balanced/loadBalanced-true-txt.json

@@ -0,0 +1,13 @@
+{
+  "uri": "mongodb+srv://test20.test.build.10gen.cc/",
+  "seeds": [
+    "localhost.test.build.10gen.cc:27017"
+  ],
+  "hosts": [
+    "localhost.test.build.10gen.cc:27017"
+  ],
+  "options": {
+    "loadBalanced": true,
+    "ssl": true
+  }
+}

Tests/Specs/initial-dns-seedlist-discovery/tests/direct-connection-false.json renamed to Tests/Specs/initial-dns-seedlist-discovery/tests/replica-set/direct-connection-false.json

@@ -9,6 +9,7 @@
     "localhost:27019"
   ],
   "options": {
-    "ssl": true
+    "ssl": true,
+    "directConnection": false
   }
 }