Xbase++ Requires Chilkat v10.1.3+

Datev OAuth2 Access Token

See more Datev Examples

Demonstrates how to get a Datev OAuth2 access token from a desktop application or script. Xbase++

LOCAL nSuccess
LOCAL oOauth2
LOCAL cUrl
LOCAL nNumMsWaited
LOCAL oSbJson

nSuccess := 0

//  To further clarify, see OAuth 2.0 Authorization Flow

oOauth2 := CreateObject("Chilkat.OAuth2")

//  Your Datev app should use "http://localhost" (no trailing forward slash) for the redirect URL.
oOauth2:ListenPort := 3017

//  

oOauth2:AuthorizationEndpoint := "https://login.datev.de/openidsandbox/authorize"
oOauth2:TokenEndpoint := "https://sandbox-api.datev.de/token"

//  Replace this with your actual client ID.
oOauth2:ClientId := "DATEV_CLIENT_ID"
oOauth2:ClientSecret := "DATEV_CLIENT_SECRET"

oOauth2:CodeChallenge := 1
oOauth2:CodeChallengeMethod := "S256"

oOauth2:Scope := "openid profile email datev:accounting:clients accounting:documents datev:accounting:extf-files-import"

//  Begin the OAuth2 authorization code flow.  This returns a URL that should be loaded in a browser.
cUrl := oOauth2:StartAuth()
IF (oOauth2:LastMethodSuccess != 1)
    ? oOauth2:LastErrorText
    oOauth2:destroy()
    RETURN
ENDIF

//  Launch the default browser on the system and navigate to the url.
//  The LaunchBrowser method was added in Chilkat v10.1.2.
nSuccess := oOauth2:LaunchBrowser(cUrl)
IF (nSuccess == 0)
    ? oOauth2:LastErrorText
    oOauth2:destroy()
    RETURN
ENDIF

//  Wait for the interactive user to grant permission in the interactive browser session.
//  We'll wait for a max of 90 seconds.
nNumMsWaited := 0
DO WHILE (nNumMsWaited < 90000) .AND. (oOauth2:AuthFlowState < 3)
    oOauth2:SleepMs(100)
    nNumMsWaited := nNumMsWaited + 100
ENDDO

//  If there was no response from the browser within 90 seconds, then 
//  the AuthFlowState will be equal to 1 or 2.
//  1: Waiting for Redirect. The OAuth2 background thread is waiting to receive the redirect HTTP request from the browser.
//  2: Waiting for Final Response. The OAuth2 background thread is waiting for the final access token response.
//  In that case, cancel the background task started in the call to StartAuth.
IF (oOauth2:AuthFlowState < 3)
    oOauth2:Cancel()
    ? "No response from the browser!"
    oOauth2:destroy()
    RETURN
ENDIF

//  Check the AuthFlowState to see if authorization was granted, denied, or if some error occurred
//  The possible AuthFlowState values are:
//  3: Completed with Success. The OAuth2 flow has completed, the background thread exited, and the successful JSON response is available in AccessTokenResponse property.
//  4: Completed with Access Denied. The OAuth2 flow has completed, the background thread exited, and the error JSON is available in AccessTokenResponse property.
//  5: Failed Prior to Completion. The OAuth2 flow failed to complete, the background thread exited, and the error information is available in the FailureInfo property.
IF (oOauth2:AuthFlowState == 5)
    ? "OAuth2 failed to complete."
    ? oOauth2:FailureInfo
    oOauth2:destroy()
    RETURN
ENDIF

IF (oOauth2:AuthFlowState == 4)
    ? "OAuth2 authorization was denied."
    ? oOauth2:AccessTokenResponse
    oOauth2:destroy()
    RETURN
ENDIF

IF (oOauth2:AuthFlowState != 3)
    ? "Unexpected AuthFlowState:" + Str(oOauth2:AuthFlowState)
    oOauth2:destroy()
    RETURN
ENDIF

//  Save the full JSON access token response to a file.
oSbJson := CreateObject("Chilkat.StringBuilder")
oSbJson:Append(oOauth2:AccessTokenResponse)
oSbJson:WriteFile("qa_data/tokens/datev.json", "utf-8", 0)

//  The saved JSON response looks like this:

//  {
//  	"refresh_token": "ZDA5Y .... FFhTXc9",
//  	"refresh_token_expires_in": 39600,
//  	"id_token": "eyJ .... Q9w",
//  	"access_token": "MTM .... 1UDA9",
//  	"token_type": "bearer",
//  	"expires_in": 900		
//  }

? "OAuth2 authorization granted!"
? "Access Token = " + oOauth2:AccessToken

oOauth2:destroy()
oSbJson:destroy()