Menulis sumber daya DSC di C#

Berlaku Untuk: Windows PowerShell 4.0, Windows PowerShell 5.0

Biasanya, sumber daya kustom Windows PowerShell Desired State Configuration (DSC) diimplementasikan dalam skrip PowerShell. Namun, Anda juga dapat menerapkan fungsionalitas sumber daya kustom DSC dengan menulis cmdlet di C#. Untuk pengenalan tentang menulis cmdlet di C#, lihat Menulis cmdlet Windows PowerShell.

Selain menerapkan sumber daya dalam C# sebagai cmdlet, proses pembuatan skema MOF, membuat struktur folder, mengimpor, dan menggunakan sumber daya DSC kustom Anda sama seperti yang dijelaskan dalam Menulis sumber daya DSC kustom dengan MOF.

Menulis sumber daya berbasis cmdlet

Untuk contoh ini, kami akan menerapkan sumber daya sederhana yang mengelola file teks dan kontennya.

Menulis skema MOF

Berikut ini adalah definisi sumber daya MOF.

[ClassVersion("1.0.0"), FriendlyName("xDemoFile")]
class MSFT_XDemoFile : OMI_BaseResource
{
     [Key, Description("path")] String Path;
     [Write, Description("Should the file be present"), ValueMap{"Present","Absent"}, Values{"Present","Absent"}] String Ensure;
     [Write, Description("Contentof file.")] String Content;
};

Menyiapkan proyek Visual Studio

Menyiapkan proyek cmdlet

1. Buka Visual Studio.
2. Buat proyek C# dan berikan nama.
3. Pilih Pustaka Kelas dari templat proyek yang tersedia.
4. Klik Ok.
5. Tambahkan referensi perakitan ke System.Automation.Management.dll ke proyek Anda.
6. Ubah nama rakitan agar sesuai dengan nama sumber daya. Dalam hal ini, rakitan harus diberi nama MSFT_XDemoFile.

Menulis kode cmdlet

Kode C# berikut mengimplementasikan Get-TargetResourcecmdlet , Set-TargetResource, dan Test-TargetResource .

namespace cSharpDSCResourceExample
{
    using System;
    using System.Collections.Generic;
    using System.IO;
    using System.Management.Automation;  // Windows PowerShell assembly.

    #region Get-TargetResource

    [OutputType(typeof(System.Collections.Hashtable))]
    [Cmdlet(VerbsCommon.Get, "TargetResource")]
    public class GetTargetResource : PSCmdlet
    {
        [Parameter(Mandatory = true)]
        public string Path { get; set; }

        /// <summary>
        /// Implement the logic to return the current state of the resource as a hashtable with
        /// keys being the resource properties and the values are the corresponding current
        /// value on the machine.
        /// </summary>
        protected override void ProcessRecord()
        {
            var currentResourceState = new Dictionary<string, string>();
            if (File.Exists(Path))
            {
                currentResourceState.Add("Ensure", "Present");

                // read current content
                string CurrentContent = "";
                using (var reader = new StreamReader(Path))
                {
                    CurrentContent = reader.ReadToEnd();
                }
                currentResourceState.Add("Content", CurrentContent);
            }
            else
            {
                currentResourceState.Add("Ensure", "Absent");
                currentResourceState.Add("Content", "");
            }
            // write the hashtable in the PS console.
            WriteObject(currentResourceState);
        }
    }

    # endregion

    #region Set-TargetResource
    [OutputType(typeof(void))]
    [Cmdlet(VerbsCommon.Set, "TargetResource")]
    public class SetTargetResource : PSCmdlet
    {
        [Parameter(Mandatory = true)]
        public string Path { get; set; }

        [Parameter(Mandatory = false)]

        [ValidateSet("Present", "Absent", IgnoreCase = true)]
        public string Ensure {
            get
            {
                // set the default to present.
               return (this._ensure ?? "Present") ;
            }
            set
            {
                this._ensure = value;
            }
        }

        [Parameter(Mandatory = false)]
        public string Content {
            get { return (string.IsNullOrEmpty(this._content) ? "" : this._content); }
            set { this._content = value; }
        }

        private string _ensure;
        private string _content;

        /// <summary>
        /// Implement the logic to set the state of the machine to the desired state.
        /// </summary>
        protected override void ProcessRecord()
        {
            WriteVerbose(string.Format("Running set with parameters {0}{1}{2}", Path, Ensure, Content));
            if (File.Exists(Path))
            {
                if (Ensure.Equals("absent", StringComparison.InvariantCultureIgnoreCase))
                {
                    File.Delete(Path);
                }
                else
                {
                    // file already exist and ensure "present" is specified. start writing the content to a file
                    if (!string.IsNullOrEmpty(Content))
                    {
                        string existingContent = null;
                        using (var reader = new StreamReader(Path))
                        {
                            existingContent = reader.ReadToEnd();
                        }
                        // check if the content of the file mathes the content passed
                        if (!existingContent.Equals(Content, StringComparison.InvariantCultureIgnoreCase))
                        {
                            WriteVerbose("Existing content did not match with desired content updating the content of the file");
                            using (var writer = new StreamWriter(Path))
                            {
                                writer.Write(Content);
                                writer.Flush();
                            }
                        }
                    }
                }

            }
            else
            {
                if (Ensure.Equals("present", StringComparison.InvariantCultureIgnoreCase))
                {
                    // if nothing is passed for content just write "" otherwise write the content passed.
                    using (var writer = new StreamWriter(Path))
                    {
                        WriteVerbose(string.Format("Creating a file under path {0} with content {1}", Path, Content));
                        writer.Write(Content);
                    }
                }

            }

            /* if you need to reboot the VM. please add the following two line of code.
            PSVariable DscMachineStatus = new PSVariable("DSCMachineStatus", 1, ScopedItemOptions.AllScope);
            this.SessionState.PSVariable.Set(DscMachineStatus);
             */

        }

    }

    # endregion

    #region Test-TargetResource

    [Cmdlet("Test", "TargetResource")]
    [OutputType(typeof(Boolean))]
    public class TestTargetResource : PSCmdlet
    {
        [Parameter(Mandatory = true)]
        public string Path { get; set; }

        [Parameter(Mandatory = false)]

        [ValidateSet("Present", "Absent", IgnoreCase = true)]
        public string Ensure
        {
            get
            {
                // set the default to present.
                return (this._ensure ?? "Present");
            }
            set
            {
                this._ensure = value;
            }
        }

        [Parameter(Mandatory = false)]
        public string Content
        {
            get { return (string.IsNullOrEmpty(this._content) ? "" : this._content); }
            set { this._content = value; }
        }

        private string _ensure;
        private string _content;

        /// <summary>
        /// Return a boolean value which indicates wheather the current machine is in desired state or not.
        /// </summary>
        protected override void ProcessRecord()
        {
            if (File.Exists(Path))
            {
                if( Ensure.Equals("absent", StringComparison.InvariantCultureIgnoreCase))
                {
                    WriteObject(false);
                }
                else
                {
                    // check if the content matches

                    string existingContent = null;
                    using (var stream = new StreamReader(Path))
                    {
                        existingContent = stream.ReadToEnd();
                    }

                    WriteObject(Content.Equals(existingContent, StringComparison.InvariantCultureIgnoreCase));
                }
            }
            else
            {
                WriteObject(Ensure.Equals("Absent", StringComparison.InvariantCultureIgnoreCase));
            }
        }
    }

    # endregion

}

Menyebarkan sumber daya

File dll yang dikompilasi harus disimpan dalam struktur file yang mirip dengan sumber daya berbasis skrip. Berikut ini adalah struktur folder untuk sumber daya ini.

$env: psmodulepath (folder)
    |- MyDscResources (folder)
        |- MyDscResources.psd1 (file, required)
        |- DSCResources (folder)
            |- MSFT_XDemoFile (folder)
                |- MSFT_XDemoFile.psd1 (file, optional)
                |- MSFT_XDemoFile.dll (file, required)
                |- MSFT_XDemoFile.schema.mof (file, required)

Lihat juga

Konsep

Menulis sumber daya DSC kustom dengan MOF

Sumber Daya Lain

Menulis Cmdlet Windows PowerShell