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C

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 C Downloads

C
#include <C_CkHttp.h>
#include <C_CkJsonObject.h>
#include <C_CkHttpRequest.h>
#include <C_CkHttpResponse.h>
#include <C_CkStringBuilder.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkHttp http;
    HCkJsonObject json;
    HCkHttpRequest req;
    HCkHttpResponse resp;
    HCkStringBuilder sbResponseBody;
    HCkJsonObject jResp;
    int respStatusCode;
    const char *access_token;

    success = FALSE;

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

    http = CkHttp_Create();

    // 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_putLogin(http,"DROPBOX_APP_KEY");
    CkHttp_putPassword(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 = CkJsonObject_Create();
    success = CkJsonObject_LoadFile(json,"qa_data/tokens/dropbox.json");
    if (success == FALSE) {
        printf("%s\n",CkJsonObject_lastErrorText(json));
        CkHttp_Dispose(http);
        CkJsonObject_Dispose(json);
        return;
    }

    req = CkHttpRequest_Create();
    CkHttpRequest_AddParam(req,"grant_type","refresh_token");
    CkHttpRequest_AddParam(req,"refresh_token",CkJsonObject_stringOf(json,"refresh_token"));

    CkHttpRequest_putHttpVerb(req,"POST");
    CkHttpRequest_putContentType(req,"application/x-www-form-urlencoded");

    resp = CkHttpResponse_Create();
    success = CkHttp_HttpReq(http,"https://api.dropbox.com/oauth2/token",req,resp);
    if (success == FALSE) {
        printf("%s\n",CkHttp_lastErrorText(http));
        CkHttp_Dispose(http);
        CkJsonObject_Dispose(json);
        CkHttpRequest_Dispose(req);
        CkHttpResponse_Dispose(resp);
        return;
    }

    sbResponseBody = CkStringBuilder_Create();
    CkHttpResponse_GetBodySb(resp,sbResponseBody);

    jResp = CkJsonObject_Create();
    CkJsonObject_LoadSb(jResp,sbResponseBody);
    CkJsonObject_putEmitCompact(jResp,FALSE);

    printf("Response Body:\n");
    printf("%s\n",CkJsonObject_emit(jResp));

    respStatusCode = CkHttpResponse_getStatusCode(resp);
    printf("Response Status Code = %d\n",respStatusCode);
    if (respStatusCode >= 400) {
        printf("Response Header:\n");
        printf("%s\n",CkHttpResponse_header(resp));
        printf("Failed.\n");
        CkHttp_Dispose(http);
        CkJsonObject_Dispose(json);
        CkHttpRequest_Dispose(req);
        CkHttpResponse_Dispose(resp);
        CkStringBuilder_Dispose(sbResponseBody);
        CkJsonObject_Dispose(jResp);
        return;
    }

    // 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 = CkJsonObject_stringOf(jResp,"access_token");
    printf("New Access Token: %s\n",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_UpdateString(json,"access_token",access_token);

    CkJsonObject_WriteFile(json,"qa_data/tokens/dropbox.json");


    CkHttp_Dispose(http);
    CkJsonObject_Dispose(json);
    CkHttpRequest_Dispose(req);
    CkHttpResponse_Dispose(resp);
    CkStringBuilder_Dispose(sbResponseBody);
    CkJsonObject_Dispose(jResp);

    }