Powershell to call GitHub Api using personal token

CallGitHubApi.ps1

function CreateGitHubRequestHeaders([string]$username, [string]$token){
    [Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12
    $base64AuthInfo = [Convert]::ToBase64String([Text.Encoding]::ASCII.GetBytes(("{0}:{1}" -f $username,$token)))
    $headers = @{Authorization="Basic $base64AuthInfo"}
    return $headers
}

function GetRestfulErrorResponse($exception) {
    $ret = ""
    if($exception.Exception -and $exception.Exception.Response){
        $result = $exception.Exception.Response.GetResponseStream()
        $reader = New-Object System.IO.StreamReader($result)
        $reader.BaseStream.Position = 0
        $reader.DiscardBufferedData()
        $ret = $reader.ReadToEnd()
        $reader.Close()
    }
    if($ret -eq $null -or $ret.Trim() -eq ""){
        $ret = $exception.ToString()
    }
    return $ret
}

$headers = CreateGitHubRequestHeaders -username <your user name> -token <your token>

$url = 'https://api.github.com//repos/<YourAccount>/<YourRepo>/<the endpoint>'
$body = @{
        # whatever required by the endpoint
        # head = "$head"
        # base = "$base"        
    } | ConvertTo-Json
Try{
    Invoke-RestMethod -Method <Post|Get|Put> `
            -Uri $url `
            -Headers $headers `
            -Body $body # for POST and PUT
} Catch {
    $resp = (GetRestfulErrorResponse $_)
    Write-Error $resp
    throw
}