NixOS · Dec 3, 2019 · Dec 3, 2019 · Dec 4, 2019 · Dec 4, 2019 · Dec 4, 2019
diff --git a/nixos/lib/test-driver/test-driver.py b/nixos/lib/test-driver/test-driver.py
@@ -312,8 +312,13 @@ def send_monitor_command(self, command: str) -> str:
         self.monitor.send(message)
         return self.wait_for_monitor_prompt()
 
-    def wait_for_unit(self, unit: str, user: Optional[str] = None) -> bool:
-        while True:
+    def wait_for_unit(self, unit: str, user: Optional[str] = None) -> None:
+        """Wait for a systemd unit to get into "active" state.
+        Throws exceptions on "failed" and "inactive" states as well as
+        after timing out.
+        """
+
+        def check_active(_: Any) -> bool:
             info = self.get_unit_info(unit, user)
             state = info["ActiveState"]
             if state == "failed":
@@ -329,8 +334,10 @@ def wait_for_unit(self, unit: str, user: Optional[str] = None) -> bool:
                                 'unit "{}" is inactive and there ' "are no pending jobs"
                             ).format(unit)
                         )
-            if state == "active":
-                return True
+
+            return state == "active"
+
+        retry(check_active)
 
     def get_unit_info(self, unit: str, user: Optional[str] = None) -> Dict[str, str]:
         status, lines = self.systemctl('--no-pager show "{}"'.format(unit), user)
@@ -421,18 +428,34 @@ def fail(self, *commands: str) -> None:
                     )
 
     def wait_until_succeeds(self, command: str) -> str:
+        """Wait until a command returns success and return its output.
+        Throws an exception on timeout.
+        """
+        output = ""
+
+        def check_success(_: Any) -> bool:
+            nonlocal output
+            status, output = self.execute(command)
+            return status == 0
+
         with self.nested("waiting for success: {}".format(command)):
-            while True:
-                status, output = self.execute(command)
-                if status == 0:
-                    return output
+            retry(check_success)
+            return output
 
     def wait_until_fails(self, command: str) -> str:
+        """Wait until a command returns failure.
+        Throws an exception on timeout.
+        """
+        output = ""
+
+        def check_failure(_: Any) -> bool:
+            nonlocal output
+            status, output = self.execute(command)
+            return status != 0
+
         with self.nested("waiting for failure: {}".format(command)):
-            while True:
-                status, output = self.execute(command)
-                if status != 0:
-                    return output
+            retry(check_failure)
+            return output
 
     def wait_for_shutdown(self) -> None:
         if not self.booted:
@@ -453,25 +476,38 @@ def get_tty_text(self, tty: str) -> str:
         )
         return output
 
-    def wait_until_tty_matches(self, tty: str, regexp: str) -> bool:
+    def wait_until_tty_matches(self, tty: str, regexp: str) -> None:
+        """Wait until the visible output on the chosen TTY matches regular
+        expression. Throws an exception on timeout.
+        """
         matcher = re.compile(regexp)
+
+        def tty_matches(last: bool) -> bool:
+            text = self.get_tty_text(tty)
+            if last:
+                self.log(
+                    f"Last chance to match /{regexp}/ on TTY{tty}, "
+                    f"which currently contains: {text}"
+                )
+            return len(matcher.findall(text)) > 0
+
         with self.nested("waiting for {} to appear on tty {}".format(regexp, tty)):
-            while True:
-                text = self.get_tty_text(tty)
-                if len(matcher.findall(text)) > 0:
-                    return True
+            retry(tty_matches)
 
     def send_chars(self, chars: List[str]) -> None:
         with self.nested("sending keys ‘{}‘".format(chars)):
             for char in chars:
                 self.send_key(char)
 
-    def wait_for_file(self, filename: str) -> bool:
+    def wait_for_file(self, filename: str) -> None:
+        """Waits until the file exists in machine's file system."""
+
+        def check_file(_: Any) -> bool:
+            status, _ = self.execute("test -e {}".format(filename))
+            return status == 0
+
         with self.nested("waiting for file ‘{}‘".format(filename)):
-            while True:
-                status, _ = self.execute("test -e {}".format(filename))
-                if status == 0:
-                    return True
+            retry(check_file)
 
     def wait_for_open_port(self, port: int) -> None:
         def port_is_open(_: Any) -> bool:
@@ -494,8 +530,8 @@ def start_job(self, jobname: str, user: Optional[str] = None) -> Tuple[int, str]
     def stop_job(self, jobname: str, user: Optional[str] = None) -> Tuple[int, str]:
         return self.systemctl("stop {}".format(jobname), user)
 
-    def wait_for_job(self, jobname: str) -> bool:
-        return self.wait_for_unit(jobname)
+    def wait_for_job(self, jobname: str) -> None:
+        self.wait_for_unit(jobname)
 
     def connect(self) -> None:
         if self.connected:
@@ -700,18 +736,20 @@ def wait_for_x(self) -> None:
         """Wait until it is possible to connect to the X server.  Note that
         testing the existence of /tmp/.X11-unix/X0 is insufficient.
         """
+
+        def check_x(_: Any) -> bool:
+            cmd = (
+                "journalctl -b SYSLOG_IDENTIFIER=systemd | "
+                + 'grep "Reached target Current graphical"'
+            )
+            status, _ = self.execute(cmd)
+            if status != 0:
+                return False
+            status, _ = self.execute("[ -e /tmp/.X11-unix/X0 ]")
+            return status == 0
+
         with self.nested("waiting for the X11 server"):
-            while True:
-                cmd = (
-                    "journalctl -b SYSLOG_IDENTIFIER=systemd | "
-                    + 'grep "Reached target Current graphical"'
-                )
-                status, _ = self.execute(cmd)
-                if status != 0:
-                    continue
-                status, _ = self.execute("[ -e /tmp/.X11-unix/X0 ]")
-                if status == 0:
-                    return
+            retry(check_x)
 
     def get_window_names(self) -> List[str]:
         return self.succeed(

diff --git a/nixos/tests/ldap.nix b/nixos/tests/ldap.nix
@@ -1,4 +1,4 @@
-import ./make-test.nix ({ pkgs, lib, ...} :
+import ./make-test-python.nix ({ pkgs, lib, ...} :
 
 let
   unlines = lib.concatStringsSep "\n";
@@ -288,108 +288,118 @@ in
 
     client1 = mkClient true; # use nss_pam_ldapd
     client2 = mkClient false; # use nss_ldap and pam_ldap
-
   };
 
   testScript = ''
-    $server->start;
-    $server->waitForUnit("default.target");
-
-    subtest "slapd", sub {
-      subtest "auth as database admin with SASL and check a POSIX account", sub {
-        $server->succeed(join ' ', 'test',
-         '"$(ldapsearch -LLL -H ldapi:// -Y EXTERNAL',
-             '-b \'uid=${ldapUser},ou=accounts,ou=posix,${dbSuffix}\' ',
-             '-s base uidNumber |',
-           'sed -ne \'s/^uidNumber: \\(.*\\)/\\1/p\' ',
-         ')" -eq ${toString ldapUserId}');
-      };
-      subtest "auth as database admin with password and check a POSIX account", sub {
-        $server->succeed(join ' ', 'test',
-         '"$(ldapsearch -LLL -H ldap://server',
-             '-D \'cn=admin,${dbSuffix}\' -w \'${dbAdminPwd}\' ',
-             '-b \'uid=${ldapUser},ou=accounts,ou=posix,${dbSuffix}\' ',
-             '-s base uidNumber |',
-           'sed -ne \'s/^uidNumber: \\(.*\\)/\\1/p\' ',
-         ')" -eq ${toString ldapUserId}');
-      };
-    };
-
-    $client1->start;
-    $client1->waitForUnit("default.target");
-
-    subtest "password", sub {
-      subtest "su with password to a POSIX account", sub {
-        $client1->succeed("${pkgs.expect}/bin/expect -c '" . join ';',
-          'spawn su "${ldapUser}"',
-          'expect "Password:"',
-          'send "${ldapUserPwd}\n"',
-          'expect "*"',
-          'send "whoami\n"',
-          'expect -ex "${ldapUser}" {exit}',
-          'exit 1' . "'");
-      };
-      subtest "change password of a POSIX account as root", sub {
-        $client1->succeed("chpasswd <<<'${ldapUser}:new-password'");
-        $client1->succeed("${pkgs.expect}/bin/expect -c '" . join ';',
-          'spawn su "${ldapUser}"',
-          'expect "Password:"',
-          'send "new-password\n"',
-          'expect "*"',
-          'send "whoami\n"',
-          'expect -ex "${ldapUser}" {exit}',
-          'exit 1' . "'");
-        $client1->succeed('chpasswd <<<\'${ldapUser}:${ldapUserPwd}\' ');
-      };
-      subtest "change password of a POSIX account from itself", sub {
-        $client1->succeed('chpasswd <<<\'${ldapUser}:${ldapUserPwd}\' ');
-        $client1->succeed("${pkgs.expect}/bin/expect -c '" . join ';',
-          'spawn su --login ${ldapUser} -c passwd',
-          'expect "Password: "',
-          'send "${ldapUserPwd}\n"',
-          'expect "(current) UNIX password: "',
-          'send "${ldapUserPwd}\n"',
-          'expect "New password: "',
-          'send "new-password\n"',
-          'expect "Retype new password: "',
-          'send "new-password\n"',
-          'expect "passwd: password updated successfully" {exit}',
-          'exit 1' . "'");
-        $client1->succeed("${pkgs.expect}/bin/expect -c '" . join ';',
-          'spawn su "${ldapUser}"',
-          'expect "Password:"',
-          'send "${ldapUserPwd}\n"',
-          'expect "su: Authentication failure" {exit}',
-          'exit 1' . "'");
-        $client1->succeed("${pkgs.expect}/bin/expect -c '" . join ';',
-          'spawn su "${ldapUser}"',
-          'expect "Password:"',
-          'send "new-password\n"',
-          'expect "*"',
-          'send "whoami\n"',
-          'expect -ex "${ldapUser}" {exit}',
-          'exit 1' . "'");
-        $client1->succeed('chpasswd <<<\'${ldapUser}:${ldapUserPwd}\' ');
-      };
-    };
-
-    $client2->start;
-    $client2->waitForUnit("default.target");
-
-    subtest "NSS", sub {
-        $client1->succeed("test \"\$(id -u '${ldapUser}')\" -eq ${toString ldapUserId}");
-        $client1->succeed("test \"\$(id -u -n '${ldapUser}')\" = '${ldapUser}'");
-        $client1->succeed("test \"\$(id -g '${ldapUser}')\" -eq ${toString ldapGroupId}");
-        $client1->succeed("test \"\$(id -g -n '${ldapUser}')\" = '${ldapGroup}'");
-        $client2->succeed("test \"\$(id -u '${ldapUser}')\" -eq ${toString ldapUserId}");
-        $client2->succeed("test \"\$(id -u -n '${ldapUser}')\" = '${ldapUser}'");
-        $client2->succeed("test \"\$(id -g '${ldapUser}')\" -eq ${toString ldapGroupId}");
-        $client2->succeed("test \"\$(id -g -n '${ldapUser}')\" = '${ldapGroup}'");
-    };
-
-    subtest "PAM", sub {
-        $client1->succeed("echo ${ldapUserPwd} | su -l '${ldapUser}' -c true");
-        $client2->succeed("echo ${ldapUserPwd} | su -l '${ldapUser}' -c true");
-    };
+    def expect_script(*commands):
+        script = ";".join(commands)
+        return f"${pkgs.expect}/bin/expect -c '{script}'"
+
+
+    server.start()
+    server.wait_for_unit("default.target")
+
+    with subtest("slapd: auth as database admin with SASL and check a POSIX account"):
+        server.succeed(
+            'test "$(ldapsearch -LLL -H ldapi:// -Y EXTERNAL '
+            + "-b 'uid=${ldapUser},ou=accounts,ou=posix,${dbSuffix}' "
+            + "-s base uidNumber | "
+            + "sed -ne 's/^uidNumber: \\(.*\\)/\\1/p')\" -eq ${toString ldapUserId}"
+        )
+
+    with subtest("slapd: auth as database admin with password and check a POSIX account"):
+        server.succeed(
+            "test \"$(ldapsearch -LLL -H ldap://server -D 'cn=admin,${dbSuffix}' "
+            + "-w '${dbAdminPwd}' -b 'uid=${ldapUser},ou=accounts,ou=posix,${dbSuffix}' "
+            + "-s base uidNumber | "
+            + "sed -ne 's/^uidNumber: \\(.*\\)/\\1/p')\" -eq ${toString ldapUserId}"
+        )
+
+    client1.start()
+    client1.wait_for_unit("default.target")
+
+    with subtest("password: su with password to a POSIX account"):
+        client1.succeed(
+            expect_script(
+                'spawn su "${ldapUser}"',
+                'expect "Password:"',
+                'send "${ldapUserPwd}\n"',
+                'expect "*"',
+                'send "whoami\n"',
+                'expect -ex "${ldapUser}" {exit}',
+                "exit 1",
+            )
+        )
+
+    with subtest("password: change password of a POSIX account as root"):
+        client1.succeed(
+            "chpasswd <<<'${ldapUser}:new-password'",
+            expect_script(
+                'spawn su "${ldapUser}"',
+                'expect "Password:"',
+                'send "new-password\n"',
+                'expect "*"',
+                'send "whoami\n"',
+                'expect -ex "${ldapUser}" {exit}',
+                "exit 1",
+            ),
+            "chpasswd <<<'${ldapUser}:${ldapUserPwd}'",
+        )
+
+    with subtest("password: change password of a POSIX account from itself"):
+        client1.succeed(
+            "chpasswd <<<'${ldapUser}:${ldapUserPwd}' ",
+            expect_script(
+                "spawn su --login ${ldapUser} -c passwd",
+                'expect "Password: "',
+                'send "${ldapUserPwd}\n"',
+                'expect "(current) UNIX password: "',
+                'send "${ldapUserPwd}\n"',
+                'expect "New password: "',
+                'send "new-password\n"',
+                'expect "Retype new password: "',
+                'send "new-password\n"',
+                'expect "passwd: password updated successfully" {exit}',
+                "exit 1",
+            ),
+            expect_script(
+                'spawn su "${ldapUser}"',
+                'expect "Password:"',
+                'send "${ldapUserPwd}\n"',
+                'expect "su: Authentication failure" {exit}',
+                "exit 1",
+            ),
+            expect_script(
+                'spawn su "${ldapUser}"',
+                'expect "Password:"',
+                'send "new-password\n"',
+                'expect "*"',
+                'send "whoami\n"',
+                'expect -ex "${ldapUser}" {exit}',
+                "exit 1",
+            ),
+            "chpasswd <<<'${ldapUser}:${ldapUserPwd}'",
+        )
+
+    client2.start()
+    client2.wait_for_unit("default.target")
+
+    with subtest("NSS"):
+        client1.succeed(
+            "test \"$(id -u    '${ldapUser}')\" -eq ${toString ldapUserId}",
+            "test \"$(id -u -n '${ldapUser}')\" =  '${ldapUser}'",
+            "test \"$(id -g    '${ldapUser}')\" -eq ${toString ldapGroupId}",
+            "test \"$(id -g -n '${ldapUser}')\" =  '${ldapGroup}'",
+            "test \"$(id -u    '${ldapUser}')\" -eq ${toString ldapUserId}",
+            "test \"$(id -u -n '${ldapUser}')\" =  '${ldapUser}'",
+            "test \"$(id -g    '${ldapUser}')\" -eq ${toString ldapGroupId}",
+            "test \"$(id -g -n '${ldapUser}')\" =  '${ldapGroup}'",
+        )
+
+    with subtest("PAM"):
+        client1.succeed(
+            "echo ${ldapUserPwd} | su -l '${ldapUser}' -c true",
+            "echo ${ldapUserPwd} | su -l '${ldapUser}' -c true",
+        )
   '';
 })