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Xojo Plugin

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.

Chilkat Xojo Plugin Downloads

Xojo Plugin
Dim success As Boolean
success = False

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

Dim http As New Chilkat.Http

// 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 Chilkat.JsonObject
success = json.LoadFile("qa_data/tokens/dropbox.json")
If (success = False) Then
    System.DebugLog(json.LastErrorText)
    Return
End If

Dim req As New Chilkat.HttpRequest
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 Chilkat.HttpResponse
success = http.HttpReq("https://api.dropbox.com/oauth2/token",req,resp)
If (success = False) Then
    System.DebugLog(http.LastErrorText)
    Return
End If

Dim sbResponseBody As New Chilkat.StringBuilder
success = resp.GetBodySb(sbResponseBody)

Dim jResp As New Chilkat.JsonObject
success = jResp.LoadSb(sbResponseBody)
jResp.EmitCompact = False

System.DebugLog("Response Body:")
System.DebugLog(jResp.Emit())

Dim respStatusCode As Int32
respStatusCode = resp.StatusCode
System.DebugLog("Response Status Code = " + Str(respStatusCode))
If (respStatusCode >= 400) Then
    System.DebugLog("Response Header:")
    System.DebugLog(resp.Header)
    System.DebugLog("Failed.")
    Return
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")
System.DebugLog("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")