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C

Download File from Dropbox into a String Variable

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Demonstrates how to download a file from Dropbox directly into a string variable.

Chilkat C Downloads

C
#include <C_CkRest.h>
#include <C_CkJsonObject.h>
#include <C_CkDateTime.h>
#include <C_CkDtObj.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkRest rest;
    HCkJsonObject json;
    const char *fileContent;
    const char *apiResult;
    HCkJsonObject jsonResult;
    int size;
    const char *rev;
    const char *clientModified;
    HCkDateTime ckdt;
    BOOL bLocalTime;
    HCkDtObj dt;

    success = FALSE;

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

    //  A Dropbox access token should have been previously obtained.
    //  Dropbox access tokens do not expire.
    //  See Dropbox Access Token.

    rest = CkRest_Create();

    //  Connect to Dropbox
    success = CkRest_Connect(rest,"content.dropboxapi.com",443,TRUE,TRUE);
    if (success == FALSE) {
        printf("%s\n",CkRest_lastErrorText(rest));
        CkRest_Dispose(rest);
        return;
    }

    //  Add request headers.
    CkRest_AddHeader(rest,"Authorization","Bearer DROPBOX_ACCESS_TOKEN");

    //  The download "parameters" are contained in JSON passed in an HTTP request header.
    //  This is the JSON indicating the file to be downloaded:
    //  { 
    //     "path": "/jack.txt",
    //  }

    json = CkJsonObject_Create();
    CkJsonObject_AppendString(json,"path","/jack.txt");
    CkRest_AddHeader(rest,"Dropbox-API-Arg",CkJsonObject_emit(json));

    //  The content of the file on Dropbox is returned.
    fileContent = CkRest_fullRequestNoBody(rest,"POST","/2/files/download");
    if (CkRest_getLastMethodSuccess(rest) == FALSE) {
        printf("%s\n",CkRest_lastErrorText(rest));
        CkRest_Dispose(rest);
        CkJsonObject_Dispose(json);
        return;
    }

    //  When successful, Dropbox responds with a 200 response code.
    if (CkRest_getResponseStatusCode(rest) != 200) {
        //  Examine the request/response to see what happened.
        printf("response status code = %d\n",CkRest_getResponseStatusCode(rest));
        printf("response status text = %s\n",CkRest_responseStatusText(rest));
        printf("response header: %s\n",CkRest_responseHeader(rest));
        printf("response body (if any): %s\n",fileContent);
        printf("---\n");
        printf("LastRequestStartLine: %s\n",CkRest_lastRequestStartLine(rest));
        printf("LastRequestHeader: %s\n",CkRest_lastRequestHeader(rest));
        CkRest_Dispose(rest);
        CkJsonObject_Dispose(json);
        return;
    }

    //  Show the file content that was downloaded:
    printf("%s\n",fileContent);
    printf("----\n");

    //  Information about the downloaded file is also available as JSON in a response header.
    //  The "dropbox-api-result" response header contains the information.  For example:
    apiResult = CkRest_responseHdrByName(rest,"dropbox-api-result");
    printf("%s\n",apiResult);

    //  In this case, the pretty-formatted dropbox-api-result JSON looks like this:
    //  { 
    //    "name": "jack.txt",
    //    "path_lower": "/jack.txt",
    //    "path_display": "/jack.txt",
    //    "id": "id:yqx4-tE_NKAAAAAAAAAAAQ",
    //    "client_modified": "2016-06-02T20:42:11Z",
    //    "server_modified": "2016-06-02T20:42:11Z",
    //    "rev": "8482db15f",
    //    "size": 42
    //  }

    //  Load the JSON, pretty-print it, and demonstrate how to get some values...
    jsonResult = CkJsonObject_Create();
    CkJsonObject_putEmitCompact(jsonResult,FALSE);
    CkJsonObject_Load(jsonResult,apiResult);
    //  Show the JSON pretty-printed...
    printf("%s\n",CkJsonObject_emit(jsonResult));

    //  Sample code to get data from the JSON response:
    size = CkJsonObject_IntOf(jsonResult,"size");
    printf("size = %d\n",size);

    rev = CkJsonObject_stringOf(jsonResult,"rev");
    printf("rev = %s\n",rev);

    clientModified = CkJsonObject_stringOf(jsonResult,"client_modified");
    ckdt = CkDateTime_Create();
    CkDateTime_SetFromTimestamp(ckdt,clientModified);
    bLocalTime = TRUE;
    dt = CkDtObj_Create();
    CkDateTime_ToDtObj(ckdt,bLocalTime,dt);

    printf("%d/%d/%d %d:%d\n",CkDtObj_getDay(dt),CkDtObj_getMonth(dt),CkDtObj_getYear(dt),CkDtObj_getHour(dt),CkDtObj_getMinute(dt));


    CkRest_Dispose(rest);
    CkJsonObject_Dispose(json);
    CkJsonObject_Dispose(jsonResult);
    CkDateTime_Dispose(ckdt);
    CkDtObj_Dispose(dt);

    }