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PureBasic

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 PureBasic Downloads

PureBasic
IncludeFile "CkHttpResponse.pb"
IncludeFile "CkHttp.pb"
IncludeFile "CkStringBuilder.pb"
IncludeFile "CkJsonObject.pb"
IncludeFile "CkHttpRequest.pb"

Procedure ChilkatExample()

    success.i = 0

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

    http.i = CkHttp::ckCreate()
    If http.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    ; 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

    CkHttp::setCkLogin(http, "DROPBOX_APP_KEY")
    CkHttp::setCkPassword(http, "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
    json.i = CkJsonObject::ckCreate()
    If json.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    success = CkJsonObject::ckLoadFile(json,"qa_data/tokens/dropbox.json")
    If success = 0
        Debug CkJsonObject::ckLastErrorText(json)
        CkHttp::ckDispose(http)
        CkJsonObject::ckDispose(json)
        ProcedureReturn
    EndIf

    req.i = CkHttpRequest::ckCreate()
    If req.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkHttpRequest::ckAddParam(req,"grant_type","refresh_token")
    CkHttpRequest::ckAddParam(req,"refresh_token",CkJsonObject::ckStringOf(json,"refresh_token"))

    CkHttpRequest::setCkHttpVerb(req, "POST")
    CkHttpRequest::setCkContentType(req, "application/x-www-form-urlencoded")

    resp.i = CkHttpResponse::ckCreate()
    If resp.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    success = CkHttp::ckHttpReq(http,"https://api.dropbox.com/oauth2/token",req,resp)
    If success = 0
        Debug CkHttp::ckLastErrorText(http)
        CkHttp::ckDispose(http)
        CkJsonObject::ckDispose(json)
        CkHttpRequest::ckDispose(req)
        CkHttpResponse::ckDispose(resp)
        ProcedureReturn
    EndIf

    sbResponseBody.i = CkStringBuilder::ckCreate()
    If sbResponseBody.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkHttpResponse::ckGetBodySb(resp,sbResponseBody)

    jResp.i = CkJsonObject::ckCreate()
    If jResp.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkJsonObject::ckLoadSb(jResp,sbResponseBody)
    CkJsonObject::setCkEmitCompact(jResp, 0)

    Debug "Response Body:"
    Debug CkJsonObject::ckEmit(jResp)

    respStatusCode.i = CkHttpResponse::ckStatusCode(resp)
    Debug "Response Status Code = " + Str(respStatusCode)
    If respStatusCode >= 400
        Debug "Response Header:"
        Debug CkHttpResponse::ckHeader(resp)
        Debug "Failed."
        CkHttp::ckDispose(http)
        CkJsonObject::ckDispose(json)
        CkHttpRequest::ckDispose(req)
        CkHttpResponse::ckDispose(resp)
        CkStringBuilder::ckDispose(sbResponseBody)
        CkJsonObject::ckDispose(jResp)
        ProcedureReturn
    EndIf

    ; 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
    ; }

    access_token.s = CkJsonObject::ckStringOf(jResp,"access_token")
    Debug "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.)
    CkJsonObject::ckUpdateString(json,"access_token",access_token)

    CkJsonObject::ckWriteFile(json,"qa_data/tokens/dropbox.json")


    CkHttp::ckDispose(http)
    CkJsonObject::ckDispose(json)
    CkHttpRequest::ckDispose(req)
    CkHttpResponse::ckDispose(resp)
    CkStringBuilder::ckDispose(sbResponseBody)
    CkJsonObject::ckDispose(jResp)


    ProcedureReturn
EndProcedure