functions/New-DbaCredential.ps1

function New-DbaCredential {
    <#
    .SYNOPSIS
        Creates a new SQL Server credential
 
    .DESCRIPTION
        Creates a new credential
 
    .PARAMETER SqlInstance
        The target SQL Server(s)
 
    .PARAMETER SqlCredential
        Allows you to login to SQL Server using alternative credentials
 
    .PARAMETER Name
        The Credential name
 
    .PARAMETER Identity
        The Credential Identity
 
    .PARAMETER Password
        Secure string used to authenticate the Credential Identity
 
    .PARAMETER MappedClassType
        Sets the class associated with the credential.
 
    .PARAMETER ProviderName
        Sets the name of the provider
 
    .PARAMETER Force
        If credential exists, drop and recreate
 
    .PARAMETER WhatIf
        Shows what would happen if the command were to run. No actions are actually performed
 
    .PARAMETER Confirm
        Prompts you for confirmation before executing any changing operations within the command
 
    .PARAMETER EnableException
        By default, when something goes wrong we try to catch it, interpret it and give you a friendly warning message.
        This avoids overwhelming you with "sea of red" exceptions, but is inconvenient because it basically disables advanced scripting.
        Using this switch turns this "nice by default" feature off and enables you to catch exceptions with your own try/catch.
 
    .NOTES
        Tags: Certificate
        Author: Chrissy LeMaire (@cl), netnerds.net
 
        Website: https://dbatools.io
        Copyright: (c) 2018 by dbatools, licensed under MIT
        License: MIT https://opensource.org/licenses/MIT
 
    .EXAMPLE
        PS C:\> New-DbaCredential -SqlInstance Server1
 
        You will be prompted to securely enter your password, then a credential will be created in the master database on server1 if it does not exist.
 
    .EXAMPLE
        PS C:\> New-DbaCredential -SqlInstance Server1 -Confirm:$false
 
        Suppresses all prompts to install but prompts to securely enter your password and creates a credential on Server1.
 
    .EXAMPLE
        PS C:\> New-DbaCredential -SqlInstance Server1 -Name AzureBackupBlobStore -Identity '<Azure Storage Account Name>' -Password (ConvertTo-SecureString '<Azure Storage Account Access Key>' -AsPlainText -Force)
 
        Create credential on SQL Server 2012 CU2, SQL Server 2014 for use with BACKUP TO URL.
        CredentialIdentity needs to be supplied with the Azure Storage Account Name.
        Password needs to be one of the Access Keys for the account.
 
    .EXAMPLE
        PS C:\> New-DbaCredential -SqlInstance Server1 -Name 'https://<Azure Storage Account Name>.blob.core.windows.net/<Blob Store Container Name>' -Identity 'SHARED ACCESS SIGNATURE' -Password (ConvertTo-SecureString '<Shared Access Token>' -AsPlainText -Force)
 
        Create Credential on SQL Server 2016 or higher for use with BACKUP TO URL.
        Name has to be the full URL for the blob store container that will be the backup target.
        Password needs to be passed the Shared Access Token (SAS Key).
 
    #>

    [CmdletBinding(SupportsShouldProcess = $true)] #, ConfirmImpact = "High"
    param (
        [parameter(Mandatory, ValueFromPipeline)]
        [Alias("ServerInstance", "SqlServer")]
        [DbaInstanceParameter[]]$SqlInstance,
        [PSCredential]$SqlCredential,
        [object[]]$Name = $Identity,
        [parameter(Mandatory)]
        [Alias("CredentialIdentity")]
        [string[]]$Identity,
        [Security.SecureString]$Password,
        [ValidateSet('CryptographicProvider', 'None')]
        [string]$MappedClassType = "None",
        [string]$ProviderName,
        [switch]$Force,
        [Alias('Silent')]
        [switch]$EnableException
    )

    begin {
        $mappedclass = switch ($MappedClassType) {
            "CryptographicProvider" { 1 }
            "None" { 0 }
        }
    }

    process {
        if (!$Password) {
            Read-Host -AsSecureString -Prompt "Enter the credential password"
        }

        foreach ($instance in $SqlInstance) {
            try {
                $server = Connect-SqlInstance -SqlInstance $instance -SqlCredential $sqlcredential
            } catch {
                Stop-Function -Message "Failure" -Category ConnectionError -ErrorRecord $_ -Target $instance -Continue
            }

            foreach ($cred in $Identity) {
                $currentcred = $server.Credentials[$name]

                if ($currentcred) {
                    if ($force) {
                        Write-Message -Level Verbose -Message "Dropping credential $name"
                        $currentcred.Drop()
                    } else {
                        Stop-Function -Message "Credential exists and Force was not specified" -Target $name -Continue
                    }
                }


                if ($Pscmdlet.ShouldProcess($SqlInstance, "Creating credential for database '$cred' on $instance")) {
                    try {
                        $credential = New-Object Microsoft.SqlServer.Management.Smo.Credential -ArgumentList $server, $name
                        $credential.MappedClassType = $mappedclass
                        $credential.ProviderName = $ProviderName
                        $credential.Create($Identity, $Password)

                        Add-Member -Force -InputObject $credential -MemberType NoteProperty -Name ComputerName -value $server.ComputerName
                        Add-Member -Force -InputObject $credential -MemberType NoteProperty -Name InstanceName -value $server.ServiceName
                        Add-Member -Force -InputObject $credential -MemberType NoteProperty -Name SqlInstance -value $server.DomainInstanceName

                        Select-DefaultView -InputObject $credential -Property ComputerName, InstanceName, SqlInstance, Name, Identity, CreateDate, MappedClassType, ProviderName
                    } catch {
                        Stop-Function -Message "Failed to create credential in $cred on $instance. Exception: $($_.Exception.InnerException)" -Target $credential -InnerErrorRecord $_ -Continue
                    }
                }
            }
        }
    }
}