[cli] Add windows service commands (#26442)

Adds a new `windows` command which is available when running on
a Windows hosts. The command includes two new subcommands:

* `service install`
* `service uninstall`

The `service install` command will install the called binary into
the Windows program files directory, create a new Windows service,
setup configuration and data directories, and register the service
with the Window eventlog. If the service and/or binary already
exist, the service will be stopped, service and eventlog updated
if needed, binary replaced, and the service started again.

The `service uninstall` command will stop the service, remove the
Windows service, and deregister the service with the eventlog. It
will not remove the configuration/data directory nor will it remove
the installed binary.

website/content/commands/agent.mdx

@@ -129,6 +129,10 @@ You may, however, may pass the following configuration options as CLI arguments:
 - `-encrypt`: Set the Serf encryption key. See the [Encryption Overview][] for
   more details.
 
+- `-eventlog`: Equivalent to the [eventlog.enabled][] config option.
+
+- `-eventlog-level`: Equivalent to the [eventlog.level][] config option.
+
 - `-join=<address>`: Address of another agent to join upon starting up. This can
   be specified multiple times to specify multiple agents to join.
 
@@ -231,6 +235,8 @@ You may, however, may pass the following configuration options as CLI arguments:
 [datacenter]: /nomad/docs/configuration#datacenter
 [enabled]: /nomad/docs/configuration/acl#enabled
 [encryption overview]: /nomad/docs/secure/traffic/gossip-encryption
+[eventlog.enabled]: /nomad/docs/configuration#eventlog_enabled
+[eventlog.level]: /nomad/docs/configuration#eventlog_level
 [key_file]: /nomad/docs/configuration/consul#key_file
 [log_include_location]: /nomad/docs/configuration#log_include_location
 [log_json]: /nomad/docs/configuration#log_json

website/content/commands/windows/index.mdx

@@ -0,0 +1,22 @@
+---
+layout: docs
+page_title: 'nomad windows command reference'
+description: |
+  The `nomad windows` command interacts with the Windows host platform. Install or uninstall Nomad as a Windows service.
+---
+
+# `nomad windows` command reference 
+
+Use the `windows` command to interact with Windows host platforms.
+
+## Usage 
+
+Usage: `nomad windows <subcommand> [options]`
+
+Run `nomad windows <subcommand> -h` for help on that subcommand. The following subcommands are available:
+
+- [`windows service install`][install] - Install Nomad as a Windows service
+- [`windows service uninstall`][uninstall] - Uninstall Nomad as a Windows service
+
+[install]: /nomad/commands/windows/service-install
+[uninstall]: /nomad/commands/windows/service-uninstall

website/content/commands/windows/service-install.mdx

@@ -0,0 +1,50 @@
+---
+layout: docs
+page_title: 'nomad windows service install command reference'
+description: |
+  The `nomad windows service install` command installs the Nomad binary
+  and creates a Windows service.
+---
+
+# `nomad windows service install` command reference
+
+The `windows service install` command installs the Nomad binary and
+creates a Windows service.
+
+## Usage
+
+```plaintext
+nomad windows service install
+```
+
+The `windows service install` command installs the `nomad` binary used to
+run this command, creates a data and configuration directory, writes a basic
+Nomad configuration file, creates a Windows service to run Nomad, and
+registers the service with Windows Event Log.
+
+If Nomad has been previously installed using this command, subsequent
+executions will do the following:
+
+1. Stop the service if it is running
+1. Install the currently executing nomad binary
+1. Ensure data and configuration directories exist
+1. Write a configuration file if no configuration files are found
+1. Update the service if needed
+1. Update the Event Log configuration if needed.
+
+## Options
+
+- `-config-dir <dir>`: Directory to hold the Nomad agent configuration.
+  Defaults to "{{.ProgramFiles}}\HashiCorp\nomad\bin"
+
+- `-data-dir <dir>`: Directory to hold the Nomad agent state. Defaults
+  to "{{.ProgramData}}\HashiCorp\nomad\data"
+
+- `-install-dir <dir>`: Directory to install the Nomad binary. Defaults 
+  to "{{.ProgramData}}\HashiCorp\nomad\config"
+
+- `-reinstall`: Allow the nomad Windows service to be stopped during install.
+
+## General options
+
+@include 'general_options.mdx'

website/content/commands/windows/service-uninstall.mdx

@@ -0,0 +1,22 @@
+---
+layout: docs
+page_title: 'nomad windows service uninstall command reference'
+description: |
+  The `nomad windows service uninstall` command removes the Nomad
+  Windows service.
+---
+
+# `nomad windows service uninstall` command reference
+
+The `windows service uninstall` command removes the Nomad Windows service.
+
+## Usage
+
+```plaintext
+nomad windows service uninstall
+```
+
+The `windows service uninstall` command stops the Nomad service if
+it is currently running, deregisters the service with the Windows Event Log,
+and removes the Windows service. This command does not remove the installed
+Nomad binary or the data and configuration directories.

website/content/docs/configuration/index.mdx

@@ -176,6 +176,16 @@ testing.
   This option only works on Unix based systems. The log level inherits from
   the Nomad agent log set in `log_level`
 
+- `eventlog` - This is a nested object that configures the behavior with
+  with Windows Event Log. The following parameters are available:
+
+  - `enabled` - Enable sending Nomad agent logs to the Windows Event Log.
+
+  - `level` -  `(string: "ERROR")` - Specifies the verbosity of logs the Nomad
+    agent outputs. Valid log levels include `ERROR`, `WARN`, or `INFO` in
+    increasing order of verbosity. Level must be of equal or less verbosity as
+    defined for the [`log_level`](#log_level) parameter.
+
 - `http_api_response_headers` `(map<string|string>: nil)` - Specifies
   user-defined headers to add to the HTTP API responses.
 

website/content/docs/deploy/production/windows-service.mdx

@@ -7,9 +7,12 @@ description: |-
 
 # Install Nomad as a Windows service
 
-Nomad can be run as a native Windows service. In order to do this, you will need
-to register the Nomad application with the Windows Service Control Manager using
-[`sc.exe`], configure Nomad to log to a file, and then start the Nomad service.
+You may run Nomad as a native Windows service. Use the [windows service install][]
+command to install Nomad and create the Windows service.
+
+You may also set up the Nomad Windows service manually. Use [`sc.exe`] to register
+the Nomad application with the Windows Service Control Manager, configure Nomad to
+log to a file, and then start the Nomad service.
 
 ~> **Note:** These steps should be run in a PowerShell session with Administrator
 capabilities.
@@ -23,7 +26,7 @@ argument should include the fully qualified path to the Nomad executable and any
 arguments to the nomad command: agent, -config, etc.
 
 ```plaintext
-sc.exe create "Nomad" binPath="«full path to nomad.exe» agent -config=«path to config file or directory»" start= auto
+sc.exe create "Nomad" binPath="«full path to nomad.exe» agent -config=«path to config file or directory»" start=auto
 [SC] CreateService SUCCESS
 ```
 
@@ -93,3 +96,4 @@ restart of Nomad service is not sufficient.
 [`sc.exe`]: https://msdn.microsoft.com/en-us/library/windows/desktop/ms682107(v=vs.85).aspx
 [download]: /nomad/downloads
 [logging]: /nomad/docs/configuration#log_file
+[windows service install]: /nomad/docs/commands/windows/service-install

website/data/commands-nav-data.json

@@ -1053,5 +1053,22 @@
         "path": "volume/status"
       }
     ]
+  },
+  {
+    "title": "windows",
+    "routes": [
+      {
+        "title": "Overview",
+        "path": "windows"
+      },
+      {
+        "title": "service install",
+        "path": "windows/service-install"
+      },
+      {
+        "title": "service uninstall",
+        "path": "windows/service-uninstall"
+      }
+    ]
   }
 ]