functions/Start-DbaAgentJob.ps1

function Start-DbaAgentJob {
    <#
        .SYNOPSIS
            Starts a running SQL Server Agent Job.
 
        .DESCRIPTION
            This command starts a job then returns connected SMO object for SQL Agent Job information for each instance(s) of SQL Server.
 
        .PARAMETER SqlInstance
            SQL Server name or SMO object representing the SQL Server to connect to.
 
        .PARAMETER SqlCredential
            SqlCredential object to connect as. If not specified, current Windows login will be used.
 
        .PARAMETER Job
            The job(s) to process - this list is auto-populated from the server. If unspecified, all jobs will be processed.
 
        .PARAMETER ExcludeJob
            The job(s) to exclude - this list is auto-populated from the server.
 
        .PARAMETER Wait
            Wait for output until the job has started
 
        .PARAMETER JobCollection
            Internal parameter that enables piping
 
        .PARAMETER WhatIf
            If this switch is enabled, no actions are performed but informational messages will be displayed that explain what would happen if the command were to run.
 
        .PARAMETER Confirm
            If this switch is enabled, you will be prompted for confirmation before executing any operations that change state.
 
        .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: Job, Agent
            Website: https://dbatools.io
            Copyright: (C) Chrissy LeMaire, clemaire@gmail.com
            License: MIT https://opensource.org/licenses/MIT
 
        .LINK
            https://dbatools.io/Start-DbaAgentJob
 
        .EXAMPLE
            Start-DbaAgentJob -SqlInstance localhost
 
            Starts all running SQL Agent Jobs on the local SQL Server instance
 
        .EXAMPLE
            Get-DbaAgentJob -SqlInstance sql2016 -Job cdc.DBWithCDC_capture | Start-DbaAgentJob
 
            Starts the cdc.DBWithCDC_capture SQL Agent Job on sql2016
 
        .EXAMPLE
            Start-DbaAgentJob -SqlInstance sql2016 -Job cdc.DBWithCDC_capture
 
            Starts the cdc.DBWithCDC_capture SQL Agent Job on sql2016
 
        .EXAMPLE
            $servers | Find-DbaAgentJob -IsFailed | Start-DbaAgentJob
 
            Restarts all failed jobs on all servers in the $servers collection
 
    #>

    [CmdletBinding(SupportsShouldProcess, DefaultParameterSetName = "Default")]
    param (
        [parameter(Mandatory, ParameterSetName = "Instance")]
        [Alias("ServerInstance", "SqlServer")]
        [DbaInstanceParameter[]]$SqlInstance,
        [PSCredential]$SqlCredential,
        [string[]]$Job,
        [string[]]$ExcludeJob,
        [parameter(Mandatory, ValueFromPipeline, ParameterSetName = "Object")]
        [Microsoft.SqlServer.Management.Smo.Agent.Job[]]$JobCollection,
        [switch]$Wait,
        [switch][Alias('Silent')]$EnableException
    )

    process {
        foreach ($instance in $SqlInstance) {
            Write-Verbose "Attempting to connect to $instance"
            try {
                $server = Connect-SqlInstance -SqlInstance $instance -SqlCredential $SqlCredential
            }
            catch {
                Stop-Function -Message "Failure" -Category ConnectionError -ErrorRecord $_ -Target $instance -Continue
            }

            $jobcollection += $server.JobServer.Jobs

            if ($Job) {
                $jobcollection = $jobcollection | Where-Object Name -In $Job
            }
            if ($ExcludeJob) {
                $jobcollection = $jobcollection | Where-Object Name -NotIn $ExcludeJob
            }
        }

        foreach ($currentjob in $JobCollection) {
            $server = $currentjob.Parent.Parent
            $status = $currentjob.CurrentRunStatus
            if ($status -ne 'Idle') {
                Stop-Function -Message "$currentjob on $server is not idle ($status)" -Target $currentjob -Continue
            }

            If ($Pscmdlet.ShouldProcess($server, "Starting job $currentjob")) {
                $null = $currentjob.Start()
                Start-Sleep -Milliseconds 300
                $currentjob.Refresh()

                while ($currentjob.CurrentRunStatus -eq 'Idle' -and $i++ -lt 60) {
                    Start-Sleep -Milliseconds 100
                    $currentjob.Refresh()
                }

                if ($wait) {
                    while ($currentjob.CurrentRunStatus -ne 'Idle') {
                        Write-Message -Level Output -Message "$currentjob is $($currentjob.CurrentRunStatus)"
                        Start-Sleep -Seconds 3
                        $currentjob.Refresh()
                    }
                    $currentjob
                }
                else {
                    $currentjob
                }
            }
        }
    }
}