command modules: optional stdin_add_newline (#45170)

* stdin_add_newline: allow newline suppression on command modules

* command/shell: test for stdin_add_newline

* changelog for stdin_add_newline

changelogs/fragments/command-stdin-no-newline.yaml

@@ -0,0 +1,5 @@
+---
+minor_changes:
+- command/shell - new `stdin_add_newline` arg allows suppression of
+  automatically-added newline `\n` character to the specified in the `stdin`
+  arg.

lib/ansible/modules/commands/command.py

@@ -58,6 +58,12 @@ options:
     description:
       - Set the stdin of the command directly to the specified value.
     version_added: "2.4"
+  stdin_add_newline:
+    type: bool
+    default: yes
+    description:
+      - If set to C(yes), append a newline to stdin data.
+    version_added: "2.8"
 notes:
     -  If you want to run a command through the shell (say you are using C(<), C(>), C(|), etc), you actually want the M(shell) module instead.
        Parsing shell metacharacters can lead to unexpected commands being executed if quoting is not done correctly so it is more secure to
@@ -189,6 +195,7 @@ def main():
             # The default for this really comes from the action plugin
             warn=dict(type='bool', default=True),
             stdin=dict(required=False),
+            stdin_add_newline=dict(type='bool', default=True),
         ),
         supports_check_mode=True,
     )
@@ -201,6 +208,7 @@ def main():
     removes = module.params['removes']
     warn = module.params['warn']
     stdin = module.params['stdin']
+    stdin_add_newline = module.params['stdin_add_newline']
 
     if not shell and executable:
         module.warn("As of Ansible 2.4, the parameter 'executable' is no longer supported with the 'command' module. Not using '%s'." % executable)
@@ -255,7 +263,7 @@ def main():
     startd = datetime.datetime.now()
 
     if not module.check_mode:
-        rc, out, err = module.run_command(args, executable=executable, use_unsafe_shell=shell, encoding=None, data=stdin)
+        rc, out, err = module.run_command(args, executable=executable, use_unsafe_shell=shell, encoding=None, data=stdin, binary_data=(not stdin_add_newline))
     elif creates or removes:
         rc = 0
         out = err = b'Command would have run if not in check mode'

lib/ansible/modules/commands/shell.py

@@ -60,6 +60,12 @@ options:
     description:
       - Set the stdin of the command directly to the specified value.
     version_added: "2.4"
+  stdin_add_newline:
+    type: bool
+    default: yes
+    description:
+      - If set to C(yes), append a newline to stdin data.
+    version_added: "2.8"
 notes:
   -  If you want to execute a command securely and predictably, it may be
      better to use the M(command) module instead. Best practices when writing

test/integration/targets/command_shell/tasks/main.yml

@@ -338,5 +338,51 @@
     - shell_result7.cmd == 'cat <<EOF\nOne\n  Two\n    Three\nEOF\n'
     - shell_result7.stdout == 'One\n  Two\n    Three'
 
+- name: execute a shell command with no trailing newline to stdin
+  shell: cat > {{output_dir_test | expanduser}}/afile.txt
+  args:
+    stdin: test
+    stdin_add_newline: no
+
+- name: make sure content matches expected
+  copy:
+    dest: "{{output_dir_test | expanduser}}/afile.txt"
+    content: test
+  register: shell_result7
+  failed_when:
+    - shell_result7 is failed or
+      shell_result7 is changed
+
+- name: execute a shell command with trailing newline to stdin
+  shell: cat > {{output_dir_test | expanduser}}/afile.txt
+  args:
+    stdin: test
+    stdin_add_newline: yes
+
+- name: make sure content matches expected
+  copy:
+    dest: "{{output_dir_test | expanduser}}/afile.txt"
+    content: |
+        test
+  register: shell_result8
+  failed_when:
+    - shell_result8 is failed or
+      shell_result8 is changed
+
+- name: execute a shell command with trailing newline to stdin, default
+  shell: cat > {{output_dir_test | expanduser}}/afile.txt
+  args:
+    stdin: test
+
+- name: make sure content matches expected
+  copy:
+    dest: "{{output_dir_test | expanduser}}/afile.txt"
+    content: |
+        test
+  register: shell_result9
+  failed_when:
+    - shell_result9 is failed or
+      shell_result9 is changed
+
 - name: remove the previously created file
   file: path={{output_dir_test}}/afile.txt state=absent