Send-SlackChannelInvite.ps1

function Send-SlackChannelInvite {
    <#
    .SYNOPSIS
        Send a Slack channel invite

    .DESCRIPTION
        Send a Slack channel invite

    .PARAMETER Token
        Token to use for the Slack API

        Default value is the value set by Set-PSSlackConfig

    .PARAMETER Channel
        ID of the Channel, private group, or IM channel to send file to.

    .PARAMETER User
        One or more user IDs to invite to the channel

    .PARAMETER ForceVerbose
        If specified, don't explicitly remove verbose output from Invoke-RestMethod

        *** WARNING ***
        This will expose your token in verbose output

    .EXAMPLE
        Send-SlackChannelInvite -Token $Token `
                                -Channel ABC123ID `
                                -User XYZ890ID

    .FUNCTIONALITY
        Slack
    #>

    param (
        [string]$Token = $Script:PSSlack.Token,
        [string]$Channel,
        [string[]]$User,
        [switch]$ForceVerbose = $Script:PSSlack.ForceVerbose
    )
    process
    {
        $body = @{}
        switch ($psboundparameters.keys) {
            'Channel'     { $body.channel = $Channel }
            'User'        { $body.users = $User }
        }
        Write-Verbose "Send-SlackApi -Body $($body | Format-List | Out-String)"
        $Params = @{
            Method = 'conversations.invite'
            Body = $Body
            Token = $Token
            ForceVerbose = $ForceVerbose
        }
        $response = Send-SlackApi @Params
        
        $response
    }
}