Visual Basic 6.0

Dropbox Refresh OAuth2 Access Token

See more Dropbox Examples

Demonstrates how to mint a new access token using the refresh token obtained when originally getting the OAuth2 access token. Visual Basic 6.0

Dim success As Long
success = 0

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

Dim http As New ChilkatHttp

' Implements the following CURL command:

' curl -X GET https://api.dropbox.com/oauth2/token \
'     -d grant_type=refresh_token \
'     -d refresh_token=<YOUR_REFRESH_TOKEN> \
'     -u <YOUR_APP_KEY>:<YOUR_APP_SECRET>

' Use the following online tool to generate HTTP code from a CURL command
' Convert a cURL Command to HTTP Source Code

http.Login = "DROPBOX_APP_KEY"
http.Password = "DROPBOX_APP_SECRET"

' Get the refresh token from the JSON we saved when originally getting the access token.
' (See Get Dropbox OAuth2 Access Token w/ Refresh Token
Dim json As New ChilkatJsonObject
success = json.LoadFile("qa_data/tokens/dropbox.json")
If (success = 0) Then
    Debug.Print json.LastErrorText
    Exit Sub
End If

Dim req As New ChilkatHttpRequest
req.AddParam "grant_type","refresh_token"
req.AddParam "refresh_token",json.StringOf("refresh_token")

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

Dim resp As New ChilkatHttpResponse
success = http.HttpReq("https://api.dropbox.com/oauth2/token",req,resp)
If (success = 0) Then
    Debug.Print http.LastErrorText
    Exit Sub
End If

Dim sbResponseBody As New ChilkatStringBuilder
success = resp.GetBodySb(sbResponseBody)

Dim jResp As New ChilkatJsonObject
success = jResp.LoadSb(sbResponseBody)
jResp.EmitCompact = 0

Debug.Print "Response Body:"
Debug.Print jResp.Emit()

Dim respStatusCode As Long
respStatusCode = resp.StatusCode
Debug.Print "Response Status Code = " & respStatusCode
If (respStatusCode >= 400) Then
    Debug.Print "Response Header:"
    Debug.Print resp.Header
    Debug.Print "Failed."
    Exit Sub
End If

' Sample JSON response:
' (Sample code for parsing the JSON response is shown below)

' {
'   "access_token": "sl.AC75WPYRqOi0mxcRqlimbV9FKHu04biz5qHwatG3MTgzFK7kLrGVlM9EgP4603tE7bWw0s1rMbTKiHsf37TUshPYvq-3r0qeBr_PrZIAibN8XOQicvboiOnqx6JrDekq-w8D-tE",
'   "token_type": "bearer",
'   "expires_in": 14400
' }

Dim access_token As String
access_token = jResp.StringOf("access_token")
Debug.Print "New Access Token: " & access_token

' Perhaps update our Dropbox JSON file with the new access token.
' (The existing refresh token does not change, and can be used over and over to mint new access tokens.)
success = json.UpdateString("access_token",access_token)

success = json.WriteFile("qa_data/tokens/dropbox.json")