(PowerBuilder) Refresh a Dynamics CRM OAuth2 Access Token

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.)

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

integer li_rc
oleobject loo_Json
integer li_Success
oleobject loo_DtExpire
oleobject loo_Req
oleobject loo_Http
oleobject loo_Resp
oleobject loo_Fac

// 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.

loo_Json = create oleobject
// Use "Chilkat_9_5_0.JsonObject" for versions of Chilkat < 10.0.0
li_rc = loo_Json.ConnectToNewObject("Chilkat.JsonObject")
if li_rc < 0 then
    destroy loo_Json
    MessageBox("Error","Connecting to COM object failed")
    return
end if
li_Success = loo_Json.LoadFile("qa_data/tokens/dynamicsCrm.json")
if li_Success <> 1 then
    destroy loo_Json
    return
end if

// 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.
loo_DtExpire = create oleobject
// Use "Chilkat_9_5_0.CkDateTime" for versions of Chilkat < 10.0.0
li_rc = loo_DtExpire.ConnectToNewObject("Chilkat.CkDateTime")

loo_DtExpire.SetFromUnixTime(0,loo_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...
// 

loo_Req = create oleobject
// Use "Chilkat_9_5_0.HttpRequest" for versions of Chilkat < 10.0.0
li_rc = loo_Req.ConnectToNewObject("Chilkat.HttpRequest")

loo_Req.AddParam("grant_type","refresh_token")
loo_Req.AddParam("redirect_uri","http://localhost:3017/")
loo_Req.AddParam("client_id","DYNAMICS-CRM-CLIENT-ID")
loo_Req.AddParam("client_secret","DYNAMICS-CRM-SECRET-KEY")
loo_Req.AddParam("refresh_token",loo_Json.StringOf("refresh_token"))
loo_Req.AddParam("resource","https://mydynamicsdomain.api.crm.dynamics.com")

loo_Http = create oleobject
// Use "Chilkat_9_5_0.Http" for versions of Chilkat < 10.0.0
li_rc = loo_Http.ConnectToNewObject("Chilkat.Http")

loo_Resp = loo_Http.PostUrlEncoded("https://login.microsoftonline.com/DYNAMICS-ENDPOINT-GUID/oauth2/token",loo_Req)
if loo_Http.LastMethodSuccess <> 1 then
    Write-Debug loo_Http.LastErrorText
    destroy loo_Json
    destroy loo_DtExpire
    destroy loo_Req
    destroy loo_Http
    return
end if

// Load the JSON response.
loo_Json.Load(loo_Resp.BodyStr)
loo_Json.EmitCompact = 0

// Show the JSON response.
Write-Debug loo_Json.Emit()

Write-Debug "Response status code: " + string(loo_Resp.StatusCode)

// If the response status code is not 200, then it's an error.
if loo_Resp.StatusCode <> 200 then
    destroy loo_Json
    destroy loo_DtExpire
    destroy loo_Req
    destroy loo_Http
    return
end if

destroy loo_Resp

// 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 loo_Json.HasMember("expires_on") <> 1 then
    loo_DtExpire.SetFromCurrentSystemTime()
    loo_DtExpire.AddSeconds(loo_Json.IntOf("expires_in"))
    loo_Json.AppendString("expires_on",loo_DtExpire.GetAsUnixTimeStr(0))
end if

// Save the refreshed access token JSON to a file for future requests.
loo_Fac = create oleobject
// Use "Chilkat_9_5_0.FileAccess" for versions of Chilkat < 10.0.0
li_rc = loo_Fac.ConnectToNewObject("Chilkat.FileAccess")

loo_Fac.WriteEntireTextFile("qa_data/tokens/dynamicsCrm.json",loo_Json.Emit(),"utf-8",0)


destroy loo_Json
destroy loo_DtExpire
destroy loo_Req
destroy loo_Http
destroy loo_Fac