PowerShell

Refresh a Dynamics CRM OAuth2 Access Token

See more OAuth2 Examples

Demonstrates how to refresh an expiring Dynamics CRM access token using the refresh token. endpoint.

(If a REST API call fails with a 401 unauthorized error, an application can auto-recover by refreshing the access token, and then re-send the request using the new token.)

PowerShell

Add-Type -Path "C:\chilkat\ChilkatDotNet47-x64\ChilkatDotNet47.dll"

$success = $false

# This example requires the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

# We previously obtained an access token and saved the JSON to a file using this example:
# Get Dynamics CRM OAuth2 Access Token

# This example will examine the JSON and expiration date, and if near expiration will
# refresh the access token.

$json = New-Object Chilkat.JsonObject
$success = $json.LoadFile("qa_data/tokens/dynamicsCrm.json")
if ($success -ne $true) {
    exit
}

# The contents of the JSON look like this:
# {
#   "token_type": "Bearer",
#   "scope": "user_impersonation",
#   "expires_in": "3599",
#   "ext_expires_in": "0",
#   "expires_on": "1524783438",
#   "not_before": "1524779538",
#   "resource": "https://mydomain.api.crm.dynamics.com",
#   "access_token": "...",
#   "refresh_token": "...",
#   "id_token": "..."
# }

# The "expires_on" value is a Unix time.
$dtExpire = New-Object Chilkat.CkDateTime
$dtExpire.SetFromUnixTime($false,$json.IntOf("expires_on"))

# If this date/time expires within 10 minutes of the current system time, refresh the token.

# OK, we need to refresh the access token by sending a POST...
# 

$req = New-Object Chilkat.HttpRequest
$req.AddParam("grant_type","refresh_token")
$req.AddParam("redirect_uri","http://localhost:3017/")
$req.AddParam("client_id","DYNAMICS-CRM-CLIENT-ID")
$req.AddParam("client_secret","DYNAMICS-CRM-SECRET-KEY")
$req.AddParam("refresh_token",$json.StringOf("refresh_token"))
$req.AddParam("resource","https://mydynamicsdomain.api.crm.dynamics.com")

$http = New-Object Chilkat.Http

$req.HttpVerb = "POST"
$req.ContentType = "application/x-www-form-urlencoded"

$resp = New-Object Chilkat.HttpResponse
$success = $http.HttpReq("https://login.microsoftonline.com/DYNAMICS-ENDPOINT-GUID/oauth2/token",$req,$resp)
if ($success -eq $false) {
    $($http.LastErrorText)
    exit
}

# Load the JSON response.
$json.Load($resp.BodyStr)
$json.EmitCompact = $false

# Show the JSON response.
$($json.Emit())

$("Response status code: " + $resp.StatusCode)

# If the response status code is not 200, then it's an error.
if ($resp.StatusCode -ne 200) {
    exit
}

# If an "expires_on" member does not exist, then add the JSON member by
# getting the current system date/time and adding the "expires_in" seconds.
# This way we'll know when the token expires.
if ($json.HasMember("expires_on") -ne $true) {
    $dtExpire.SetFromCurrentSystemTime()
    $dtExpire.AddSeconds($json.IntOf("expires_in"))
    $json.AppendString("expires_on",$dtExpire.GetAsUnixTimeStr($false))
}

# Save the refreshed access token JSON to a file for future requests.
$fac = New-Object Chilkat.FileAccess
$fac.WriteEntireTextFile("qa_data/tokens/dynamicsCrm.json",$json.Emit(),"utf-8",$false)