Xojo Plugin

Datev OAuth2 Access Token

See more Datev Examples

Demonstrates how to get a Datev OAuth2 access token from a desktop application or script. Xojo Plugin

Dim success As Boolean
success = False

// To further clarify, see OAuth 2.0 Authorization Flow

Dim oauth2 As New Chilkat.OAuth2

// Your Datev app should use "http://localhost" (no trailing forward slash) for the redirect URL.
oauth2.ListenPort = 3017

// 

oauth2.AuthorizationEndpoint = "https://login.datev.de/openidsandbox/authorize"
oauth2.TokenEndpoint = "https://sandbox-api.datev.de/token"

// Replace this with your actual client ID.
oauth2.ClientId = "DATEV_CLIENT_ID"
oauth2.ClientSecret = "DATEV_CLIENT_SECRET"

oauth2.CodeChallenge = True
oauth2.CodeChallengeMethod = "S256"

oauth2.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.
Dim url As String
url = oauth2.StartAuth()
If (oauth2.LastMethodSuccess <> True) Then
    System.DebugLog(oauth2.LastErrorText)
    Return
End If

// Launch the default browser on the system and navigate to the url.
// The LaunchBrowser method was added in Chilkat v10.1.2.
success = oauth2.LaunchBrowser(url)
If (success = False) Then
    System.DebugLog(oauth2.LastErrorText)
    Return
End If

// Wait for the interactive user to grant permission in the interactive browser session.
// We'll wait for a max of 90 seconds.
Dim numMsWaited As Int32
numMsWaited = 0
While (numMsWaited < 90000) And (oauth2.AuthFlowState < 3)
    oauth2.SleepMs 100
    numMsWaited = numMsWaited + 100
Wend

// 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 (oauth2.AuthFlowState < 3) Then
    success = oauth2.Cancel()
    System.DebugLog("No response from the browser!")
    Return
End If

// 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 (oauth2.AuthFlowState = 5) Then
    System.DebugLog("OAuth2 failed to complete.")
    System.DebugLog(oauth2.FailureInfo)
    Return
End If

If (oauth2.AuthFlowState = 4) Then
    System.DebugLog("OAuth2 authorization was denied.")
    System.DebugLog(oauth2.AccessTokenResponse)
    Return
End If

If (oauth2.AuthFlowState <> 3) Then
    System.DebugLog("Unexpected AuthFlowState:" + Str(oauth2.AuthFlowState))
    Return
End If

// Save the full JSON access token response to a file.
Dim sbJson As New Chilkat.StringBuilder
success = sbJson.Append(oauth2.AccessTokenResponse)
success = sbJson.WriteFile("qa_data/tokens/datev.json","utf-8",False)

// 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		
// }

System.DebugLog("OAuth2 authorization granted!")
System.DebugLog("Access Token = " + oauth2.AccessToken)