Add resolveHostnamesBlocking() in ConnectionString and IClusterConnectionRecord.

Also, combine IClusterConnectionRecord::getConnectionString() and IClusterConnectionRecord::getMutableConnectionString() to IClusterConnectionRecord::getConnectionString(), and rename setConnectionString() to setAndPersistConnectionString().

fdbclient/AutoPublicAddress.cpp

@@ -28,7 +28,7 @@
 
 #include "fdbclient/CoordinationInterface.h"
 
-IPAddress determinePublicIPAutomatically(ClusterConnectionString const& ccs) {
+IPAddress determinePublicIPAutomatically(ClusterConnectionString& ccs) {
 	try {
 		using namespace boost::asio;
 

fdbclient/ClusterConnectionFile.actor.cpp

@@ -41,7 +41,7 @@ ClusterConnectionFile::ClusterConnectionFile(std::string const& filename, Cluste
 }
 
 // Sets the connections string held by this object and persists it.
-Future<Void> ClusterConnectionFile::setConnectionString(ClusterConnectionString const& conn) {
+Future<Void> ClusterConnectionFile::setAndPersistConnectionString(ClusterConnectionString const& conn) {
 	ASSERT(filename.size());
 	cs = conn;
 	return success(persist());

fdbclient/ClusterConnectionFile.h

@@ -35,7 +35,7 @@ public:
 	explicit ClusterConnectionFile(std::string const& filename, ClusterConnectionString const& contents);
 
 	// Sets the connections string held by this object and persists it.
-	Future<Void> setConnectionString(ClusterConnectionString const&) override;
+	Future<Void> setAndPersistConnectionString(ClusterConnectionString const&) override;
 
 	// Get the connection string stored in the file.
 	Future<ClusterConnectionString> getStoredConnectionString() override;

fdbclient/ClusterConnectionKey.actor.cpp

@@ -57,7 +57,7 @@ ACTOR Future<Reference<ClusterConnectionKey>> ClusterConnectionKey::loadClusterC
 }
 
 // Sets the connections string held by this object and persists it.
-Future<Void> ClusterConnectionKey::setConnectionString(ClusterConnectionString const& connectionString) {
+Future<Void> ClusterConnectionKey::setAndPersistConnectionString(ClusterConnectionString const& connectionString) {
 	cs = connectionString;
 	return success(persist());
 }

fdbclient/ClusterConnectionKey.actor.h

@@ -48,7 +48,7 @@ public:
 	ACTOR static Future<Reference<ClusterConnectionKey>> loadClusterConnectionKey(Database db, Key connectionStringKey);
 
 	// Sets the connections string held by this object and persists it.
-	Future<Void> setConnectionString(ClusterConnectionString const&) override;
+	Future<Void> setAndPersistConnectionString(ClusterConnectionString const&) override;
 
 	// Get the connection string stored in the database.
 	Future<ClusterConnectionString> getStoredConnectionString() override;

fdbclient/ClusterConnectionMemoryRecord.actor.cpp

@@ -23,7 +23,7 @@
 #include "flow/actorcompiler.h" // has to be last include
 
 // Sets the connections string held by this object.
-Future<Void> ClusterConnectionMemoryRecord::setConnectionString(ClusterConnectionString const& conn) {
+Future<Void> ClusterConnectionMemoryRecord::setAndPersistConnectionString(ClusterConnectionString const& conn) {
 	cs = conn;
 	return Void();
 }

fdbclient/ClusterConnectionMemoryRecord.h

@@ -36,7 +36,7 @@ public:
 	}
 
 	// Sets the connections string held by this object.
-	Future<Void> setConnectionString(ClusterConnectionString const&) override;
+	Future<Void> setAndPersistConnectionString(ClusterConnectionString const&) override;
 
 	// Returns the connection string currently held in this object (there is no persistent storage).
 	Future<ClusterConnectionString> getStoredConnectionString() override;

fdbclient/CoordinationInterface.h

@@ -75,6 +75,9 @@ public:
 	std::string toString() const;
 	static std::string getErrorString(std::string const& source, Error const& e);
 	Future<Void> resolveHostnames();
+	// This one should only be used when resolving asynchronously is impossible. For all other cases, resolveHostnames()
+	// should be preferred.
+	void resolveHostnamesBlocking();
 	void resetToUnresolved();
 
 	bool hasUnresolvedHostnames = false;
@@ -105,12 +108,10 @@ public:
 
 	// Returns the connection string currently held in this object. This may not match the stored record if it hasn't
 	// been persisted or if the persistent storage for the record has been modified externally.
-	ClusterConnectionString const& getConnectionString() const;
-
-	ClusterConnectionString* getMutableConnectionString();
+	ClusterConnectionString& getConnectionString();
 
 	// Sets the connections string held by this object and persists it.
-	virtual Future<Void> setConnectionString(ClusterConnectionString const&) = 0;
+	virtual Future<Void> setAndPersistConnectionString(ClusterConnectionString const&) = 0;
 
 	// If this record is backed by persistent storage, get the connection string from that storage. Otherwise, return
 	// the connection string stored in memory.
@@ -140,6 +141,9 @@ public:
 
 	bool hasUnresolvedHostnames() const;
 	Future<Void> resolveHostnames();
+	// This one should only be used when resolving asynchronously is impossible. For all other cases, resolveHostnames()
+	// should be preferred.
+	void resolveHostnamesBlocking();
 
 	virtual void addref() = 0;
 	virtual void delref() = 0;

fdbclient/MonitorLeader.actor.cpp

@@ -54,14 +54,10 @@ FDB_DEFINE_BOOLEAN_PARAM(ConnectionStringNeedsPersisted);
 
 // Returns the connection string currently held in this object. This may not match the stored record if it hasn't
 // been persisted or if the persistent storage for the record has been modified externally.
-ClusterConnectionString const& IClusterConnectionRecord::getConnectionString() const {
+ClusterConnectionString& IClusterConnectionRecord::getConnectionString() {
 	return cs;
 }
 
-ClusterConnectionString* IClusterConnectionRecord::getMutableConnectionString() {
-	return &cs;
-}
-
 Future<bool> IClusterConnectionRecord::upToDate() {
 	ClusterConnectionString temp;
 	return upToDate(temp);
@@ -89,6 +85,10 @@ Future<Void> IClusterConnectionRecord::resolveHostnames() {
 	return cs.resolveHostnames();
 }
 
+void IClusterConnectionRecord::resolveHostnamesBlocking() {
+	cs.resolveHostnamesBlocking();
+}
+
 std::string ClusterConnectionString::getErrorString(std::string const& source, Error const& e) {
 	if (e.code() == error_code_connection_string_invalid) {
 		return format("Invalid connection string `%s: %d %s", source.c_str(), e.code(), e.what());
@@ -129,6 +129,28 @@ Future<Void> ClusterConnectionString::resolveHostnames() {
 	}
 }
 
+void ClusterConnectionString::resolveHostnamesBlocking() {
+	if (hasUnresolvedHostnames) {
+		for (auto const& hostname : hostnames) {
+			std::vector<NetworkAddress> addresses =
+			    INetworkConnections::net()->resolveTCPEndpointBlocking(hostname.host, hostname.service);
+			NetworkAddress address = addresses[deterministicRandom()->randomInt(0, addresses.size())];
+			address.flags = 0; // Reset the parsed address to public
+			address.fromHostname = NetworkAddressFromHostname::True;
+			if (hostname.isTLS) {
+				address.flags |= NetworkAddress::FLAG_TLS;
+			}
+			coords.push_back(address);
+			networkAddressToHostname.emplace(address, hostname);
+		}
+		std::sort(coords.begin(), coords.end());
+		if (std::unique(coords.begin(), coords.end()) != coords.end()) {
+			throw connection_string_invalid();
+		}
+		hasUnresolvedHostnames = false;
+	}
+}
+
 void ClusterConnectionString::resetToUnresolved() {
 	if (hostnames.size() > 0) {
 		coords.clear();
@@ -623,7 +645,7 @@ ACTOR Future<MonitorLeaderInfo> monitorLeaderOneGeneration(Reference<IClusterCon
 					    .detail("CurrentConnectionString",
 					            info.intermediateConnRecord->getConnectionString().toString());
 				}
-				connRecord->setConnectionString(info.intermediateConnRecord->getConnectionString());
+				connRecord->setAndPersistConnectionString(info.intermediateConnRecord->getConnectionString());
 				info.intermediateConnRecord = connRecord;
 			}
 
@@ -929,7 +951,7 @@ ACTOR Future<MonitorLeaderInfo> monitorProxiesOneGeneration(
 					    .detail("CurrentConnectionString",
 					            info.intermediateConnRecord->getConnectionString().toString());
 				}
-				connRecord->setConnectionString(info.intermediateConnRecord->getConnectionString());
+				connRecord->setAndPersistConnectionString(info.intermediateConnRecord->getConnectionString());
 				info.intermediateConnRecord = connRecord;
 			}
 

fdbclient/NativeAPI.actor.cpp

@@ -1791,7 +1791,7 @@ void DatabaseContext::expireThrottles() {
 	}
 }
 
-extern IPAddress determinePublicIPAutomatically(ClusterConnectionString const& ccs);
+extern IPAddress determinePublicIPAutomatically(ClusterConnectionString& ccs);
 
 // Creates a database object that represents a connection to a cluster
 // This constructor uses a preallocated DatabaseContext that may have been created

fdbserver/LeaderElection.actor.cpp

@@ -141,7 +141,7 @@ ACTOR Future<Void> tryBecomeLeaderInternal(ServerCoordinators coordinators,
 					    .detail("StoredConnectionString", coordinators.ccr->getConnectionString().toString())
 					    .detail("CurrentConnectionString", leader.get().first.serializedInfo.toString());
 				}
-				coordinators.ccr->setConnectionString(
+				coordinators.ccr->setAndPersistConnectionString(
 				    ClusterConnectionString(leader.get().first.serializedInfo.toString()));
 				TraceEvent("LeaderForwarding")
 				    .detail("ConnStr", coordinators.ccr->getConnectionString().toString())

fdbserver/fdbserver.actor.cpp

@@ -205,7 +205,7 @@ extern void copyTest();
 extern void versionedMapTest();
 extern void createTemplateDatabase();
 // FIXME: this really belongs in a header somewhere since it is actually used.
-extern IPAddress determinePublicIPAutomatically(ClusterConnectionString const& ccs);
+extern IPAddress determinePublicIPAutomatically(ClusterConnectionString& ccs);
 
 extern const char* getSourceVersion();
 
@@ -815,7 +815,7 @@ Optional<bool> checkBuggifyOverride(const char* testFile) {
 // Takes a vector of public and listen address strings given via command line, and returns vector of NetworkAddress
 // objects.
 std::pair<NetworkAddressList, NetworkAddressList> buildNetworkAddresses(
-    const IClusterConnectionRecord& connectionRecord,
+    IClusterConnectionRecord& connectionRecord,
     const std::vector<std::string>& publicAddressStrs,
     std::vector<std::string>& listenAddressStrs) {
 	if (listenAddressStrs.size() > 0 && publicAddressStrs.size() != listenAddressStrs.size()) {

fdbserver/worker.actor.cpp

@@ -2476,7 +2476,7 @@ ACTOR Future<MonitorLeaderInfo> monitorLeaderWithDelayedCandidacyImplOneGenerati
 						    .detail("CurrentConnectionString",
 						            info.intermediateConnRecord->getConnectionString().toString());
 					}
-					connRecord->setConnectionString(info.intermediateConnRecord->getConnectionString());
+					connRecord->setAndPersistConnectionString(info.intermediateConnRecord->getConnectionString());
 					info.intermediateConnRecord = connRecord;
 				}