fix(dashboard): MySQL backups with a tcp://, unix:// or pipe:// mysql_host

mysqldump was given --host=tcp --port=//host:port for the tcp:// form the servers accept, so
backups failed. Read mysql_host the way the servers connect with it: tcp://host:port (a trailing
/database is dropped), unix:// as --socket and pipe:// as a named pipe.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

dDashboardServer/routes/BackupFiles.cpp

@@ -116,16 +116,33 @@ namespace BackupFiles {
 	}
 
 	std::vector<std::string> MysqldumpArguments(const DumpCommand& command) {
+		// mysql_host as the servers read it (MySQLDatabase::Connect): host, host:port, tcp://host:port, unix://socket or pipe://name
 		auto host = command.host;
 		std::string port;
-		if (const auto colon = host.find(':'); colon != std::string::npos) {
+		std::string socket;
-			port = host.substr(colon + 1);
+		bool pipe = false;
-			host = host.substr(0, colon);
+		if (host.starts_with("unix://")) {
+			socket = host.substr(7);
+			host.clear();
+		} else if (host.starts_with("pipe://")) {
+			socket = host.substr(7);
+			pipe = true;
+			host.clear();
+		} else {
+			if (host.starts_with("tcp://")) host = host.substr(6);
+			// A database after the address (tcp://host:port/db) is not the host's; mysql_database names it
+			if (const auto slash = host.find('/'); slash != std::string::npos) host.resize(slash);
+			if (const auto colon = host.find(':'); colon != std::string::npos) {
+				port = host.substr(colon + 1);
+				host = host.substr(0, colon);
+			}
 		}
 		std::vector<std::string> arguments{ command.program, "--defaults-extra-file=" + command.optionsFile,
 			"--single-transaction", "--quick", "--routines", "--triggers", "--hex-blob", "--no-tablespaces", "--default-character-set=utf8mb4" };
 		if (!host.empty()) arguments.push_back("--host=" + host);
 		if (!port.empty()) arguments.push_back("--port=" + port);
+		if (pipe) arguments.push_back("--protocol=PIPE");
+		if (!socket.empty()) arguments.push_back("--socket=" + socket);
 		arguments.push_back("--result-file=" + command.target);
 		if (!command.errorFile.empty()) arguments.push_back("--log-error=" + command.errorFile);
 		arguments.push_back(command.database);

dDashboardServer/routes/BackupFiles.h

@@ -39,7 +39,7 @@ namespace BackupFiles {
 	struct DumpCommand {
 		std::string program;
 		std::string optionsFile;
-		std::string host; // host or host:port
+		std::string host; // mysql_host: host, host:port, tcp://host:port, unix://socket or pipe://name
 		std::string database;
 		std::string target;
 		std::string errorFile; // mysqldump's messages; never mixed into the dump, where they would break a restore

tests/dWebTests/SecurityFixesTests.cpp

@@ -121,3 +121,32 @@ TEST(BackupFilesTests, MysqldumpArgumentsAreAVector) {
 	// Passed as one literal argument, never interpreted
 	EXPECT_EQ(arguments.back(), "dlu$(touch x)");
 }
+
+// mysql_host in every form the servers connect with
+TEST(BackupFilesTests, MysqldumpArgumentsReadEveryHostForm) {
+	const auto has = [](const std::vector<std::string>& arguments, const std::string& argument) {
+		return std::find(arguments.begin(), arguments.end(), argument) != arguments.end();
+	};
+	const auto dump = [](const std::string& host) { return BackupFiles::MysqldumpArguments({ "mysqldump", "/tmp/opt", host, "dlu", "/b/x", "" }); };
+
+	auto arguments = dump("tcp://10.0.0.5:3307");
+	EXPECT_TRUE(has(arguments, "--host=10.0.0.5"));
+	EXPECT_TRUE(has(arguments, "--port=3307"));
+
+	arguments = dump("tcp://db.local:3306/dlu");
+	EXPECT_TRUE(has(arguments, "--host=db.local"));
+	EXPECT_TRUE(has(arguments, "--port=3306"));
+
+	arguments = dump("db.local");
+	EXPECT_TRUE(has(arguments, "--host=db.local"));
+	EXPECT_FALSE(std::any_of(arguments.begin(), arguments.end(), [](const std::string& a) { return a.starts_with("--port="); }));
+
+	arguments = dump("unix:///run/mysqld/mysqld.sock");
+	EXPECT_TRUE(has(arguments, "--socket=/run/mysqld/mysqld.sock"));
+	EXPECT_FALSE(std::any_of(arguments.begin(), arguments.end(), [](const std::string& a) { return a.starts_with("--host=") || a.starts_with("--port="); }));
+
+	arguments = dump("pipe://MySQL");
+	EXPECT_TRUE(has(arguments, "--protocol=PIPE"));
+	EXPECT_TRUE(has(arguments, "--socket=MySQL"));
+	EXPECT_EQ(arguments.back(), "dlu");
+}