Add terminal_initial_newline to network_cli module

changelogs/fragments/terminal_initial_newline.yaml

@@ -0,0 +1,2 @@
+minor_changes:
+  - network_cli - add `terminal_initial_newline` parameter as an option for terminal plugins.

docs/ansible.netcommon.network_cli_connection.rst

@@ -540,6 +540,26 @@ Parameters
                         <div>The answer to reply with if the <code>terminal_initial_prompt</code> is matched. The value can be a single answer or a list of answers for multiple terminal_initial_prompt. In case the login menu has multiple prompts the sequence of the prompt and excepted answer should be in same order and the value of <em>terminal_prompt_checkall</em> should be set to <em>True</em> if all the values in <code>terminal_initial_prompt</code> are expected to be matched and set to <em>False</em> if any one login prompt is to be matched.</div>
                 </td>
             </tr>
+            <tr>
+                <td colspan="1">
+                    <div class="ansibleOptionAnchor" id="parameter-"></div>
+                    <b>terminal_initial_newline</b>
+                    <a class="ansibleOptionLink" href="#parameter-" title="Permalink to this option"></a>
+                    <div style="font-size: small">
+                        <span style="color: purple">boolean</span>
+                    </div>
+                </td>
+                <td>
+                        <b>Default:</b><br/><div style="color: blue">"no"</div>
+                </td>
+                    <td>
+                                <div>var: ansible_terminal_initial_newline</div>
+                    </td>
+                <td>
+                        <div>This boolean flag, that when set to <em>True</em> will send newline on initial connection establishment to the remote device.</div>
+                        <div>This can be useful for equipment which does not send an initial header until it receives some input, like Serial-to-SSH multiplexer hardware.</div>
+                </td>
+            </tr>
             <tr>
                 <td colspan="1">
                     <div class="ansibleOptionAnchor" id="parameter-"></div>

plugins/connection/network_cli.py

@@ -198,6 +198,16 @@
       response, for example I('re.I').
     vars:
     - name: ansible_terminal_stderr_re
+  terminal_initial_newline:
+    type: boolean
+    description:
+    - This boolean flag, that when set to I(True) will send newline on initial
+      connection establishment to the remote device.
+    - This can be useful for equipment which does not send an initial header until
+      it receives some input, like Serial-to-SSH multiplexer hardware.
+    default: false
+    vars:
+    - name: ansible_terminal_initial_newline
   terminal_initial_prompt:
     type: list
     elements: string
@@ -658,6 +668,11 @@ def _connect(self):
                 "loaded terminal plugin for network_os %s" % self._network_os,
             )
 
+            terminal_initial_newline = (
+                self.get_option("terminal_initial_newline")
+                or self._terminal.terminal_initial_newline
+            )
+
             terminal_initial_prompt = (
                 self.get_option("terminal_initial_prompt") or self._terminal.terminal_initial_prompt
             )
@@ -670,6 +685,9 @@ def _connect(self):
             )
             check_all = self.get_option("terminal_initial_prompt_checkall") or False
 
+            if terminal_initial_newline:
+                self.send(command=b"", sendonly=True, newline=True)
+
             self.receive(
                 prompts=terminal_initial_prompt,
                 answer=terminal_initial_answer,

plugins/plugin_utils/terminal_base.py

@@ -40,6 +40,9 @@ class TerminalBase(TerminalBaseBase):
         re.compile(rb"\x1b\[m"),  # ANSI reset code
     ]
 
+    #: Send newline after initial session connection
+    terminal_initial_newline = False
+
     #: terminal initial prompt
     terminal_initial_prompt = None