(DataFlex) 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.

For more information, see https://www.dropbox.com/developers/documentation/http/documentation

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

Use ChilkatAx-win32.pkg

Procedure Test
    Handle hoHttp
    Boolean iSuccess
    Handle hoJson
    Variant vReq
    Handle hoReq
    Variant vResp
    Handle hoResp
    Variant vSbResponseBody
    Handle hoSbResponseBody
    Handle hoJResp
    Integer iRespStatusCode
    String sAccess_token
    String sTemp1
    Boolean bTemp1

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

    Get Create (RefClass(cComChilkatHttp)) To hoHttp
    If (Not(IsComObjectCreated(hoHttp))) Begin
        Send CreateComObject of hoHttp
    End

    // 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

    Set ComLogin Of hoHttp To "DROPBOX_APP_KEY"
    Set ComPassword Of hoHttp To "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
    Get Create (RefClass(cComChilkatJsonObject)) To hoJson
    If (Not(IsComObjectCreated(hoJson))) Begin
        Send CreateComObject of hoJson
    End
    Get ComLoadFile Of hoJson "qa_data/tokens/dropbox.json" To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoJson To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    Get Create (RefClass(cComChilkatHttpRequest)) To hoReq
    If (Not(IsComObjectCreated(hoReq))) Begin
        Send CreateComObject of hoReq
    End
    Send ComAddParam To hoReq "grant_type" "refresh_token"
    Get ComStringOf Of hoJson "refresh_token" To sTemp1
    Send ComAddParam To hoReq "refresh_token" sTemp1

    Get pvComObject of hoReq to vReq
    Get ComPostUrlEncoded Of hoHttp "https://api.dropbox.com/oauth2/token" vReq To vResp
    If (IsComObject(vResp)) Begin
        Get Create (RefClass(cComChilkatHttpResponse)) To hoResp
        Set pvComObject Of hoResp To vResp
    End
    Get ComLastMethodSuccess Of hoHttp To bTemp1
    If (bTemp1 = False) Begin
        Get ComLastErrorText Of hoHttp To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    Get Create (RefClass(cComChilkatStringBuilder)) To hoSbResponseBody
    If (Not(IsComObjectCreated(hoSbResponseBody))) Begin
        Send CreateComObject of hoSbResponseBody
    End
    Get pvComObject of hoSbResponseBody to vSbResponseBody
    Get ComGetBodySb Of hoResp vSbResponseBody To iSuccess

    Get Create (RefClass(cComChilkatJsonObject)) To hoJResp
    If (Not(IsComObjectCreated(hoJResp))) Begin
        Send CreateComObject of hoJResp
    End
    Get pvComObject of hoSbResponseBody to vSbResponseBody
    Get ComLoadSb Of hoJResp vSbResponseBody To iSuccess
    Set ComEmitCompact Of hoJResp To False

    Showln "Response Body:"
    Get ComEmit Of hoJResp To sTemp1
    Showln sTemp1

    Get ComStatusCode Of hoResp To iRespStatusCode
    Showln "Response Status Code = " iRespStatusCode
    If (iRespStatusCode >= 400) Begin
        Showln "Response Header:"
        Get ComHeader Of hoResp To sTemp1
        Showln sTemp1
        Showln "Failed."
        Send Destroy of hoResp
        Procedure_Return
    End

    Send Destroy of hoResp

    // 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
    // }

    Get ComStringOf Of hoJResp "access_token" To sAccess_token
    Showln "New Access Token: " sAccess_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.)
    Get ComUpdateString Of hoJson "access_token" sAccess_token To iSuccess

    Get ComWriteFile Of hoJson "qa_data/tokens/dropbox.json" To iSuccess


End_Procedure