DataFlex

Download File from Dropbox (Streaming)

See more Dropbox Examples

Downloads a file from Dropbox, streaming it directly to a file in the filesystem. DataFlex

Use ChilkatAx-win32.pkg

Procedure Test
    Boolean iSuccess
    Handle hoRest
    Handle hoJson
    Variant vFileStream
    Handle hoFileStream
    Integer iExpectedStatus
    String sResponseStr
    String sApiResult
    Handle hoJsonResult
    Integer iSize
    String sRev
    String sClientModified
    Handle hoCkdt
    Boolean iBLocalTime
    Variant vDt
    Handle hoDt
    String sTemp1
    Integer iTemp1
    Integer iTemp2
    Integer iTemp3
    Integer iTemp4
    Integer iTemp5
    Boolean bTemp1

    Move False To iSuccess

    // 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.

    Get Create (RefClass(cComChilkatRest)) To hoRest
    If (Not(IsComObjectCreated(hoRest))) Begin
        Send CreateComObject of hoRest
    End

    // Connect to Dropbox
    Get ComConnect Of hoRest "content.dropboxapi.com" 443 True True To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoRest To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // Add request headers.
    Get ComAddHeader Of hoRest "Authorization" "Bearer DROPBOX_ACCESS_TOKEN" To iSuccess

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

    Get Create (RefClass(cComChilkatJsonObject)) To hoJson
    If (Not(IsComObjectCreated(hoJson))) Begin
        Send CreateComObject of hoJson
    End
    Get ComAppendString Of hoJson "path" "/Homework/lit/hamlet.xml" To iSuccess
    Get ComEmit Of hoJson To sTemp1
    Get ComAddHeader Of hoRest "Dropbox-API-Arg" sTemp1 To iSuccess

    // Setup a file stream for the download
    Get Create (RefClass(cComChilkatStream)) To hoFileStream
    If (Not(IsComObjectCreated(hoFileStream))) Begin
        Send CreateComObject of hoFileStream
    End
    Set ComSinkFile Of hoFileStream To "qa_output/hamletFromDropbox.xml"

    // Indicate that the call to FullRequestNoBody should send the response body
    // to fileStream if the response status code is 200.
    // If a non-success response status code is received, then nothing
    // is streamed to the output file and the error response is returned by FullRequestNoBody.
    Move 200 To iExpectedStatus
    Get pvComObject of hoFileStream to vFileStream
    Get ComSetResponseBodyStream Of hoRest iExpectedStatus True vFileStream To iSuccess

    Get ComFullRequestNoBody Of hoRest "POST" "/2/files/download" To sResponseStr
    Get ComLastMethodSuccess Of hoRest To bTemp1
    If (bTemp1 = False) Begin
        Get ComLastErrorText Of hoRest To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // When successful, Dropbox responds with a 200 response code.
    Get ComResponseStatusCode Of hoRest To iTemp1
    If (iTemp1 <> 200) Begin
        // Examine the request/response to see what happened.
        Get ComResponseStatusCode Of hoRest To iTemp1
        Showln "response status code = " iTemp1
        Get ComResponseStatusText Of hoRest To sTemp1
        Showln "response status text = " sTemp1
        Get ComResponseHeader Of hoRest To sTemp1
        Showln "response header: " sTemp1
        Showln "response body (if any): " sResponseStr
        Showln "---"
        Get ComLastRequestStartLine Of hoRest To sTemp1
        Showln "LastRequestStartLine: " sTemp1
        Get ComLastRequestHeader Of hoRest To sTemp1
        Showln "LastRequestHeader: " sTemp1
        Procedure_Return
    End

    // 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:
    Get ComResponseHdrByName Of hoRest "dropbox-api-result" To sApiResult
    Showln sApiResult

    // In this case, the pretty-formatted dropbox-api-result JSON looks like this:
    // { 
    //   "name": "hamlet.xml",
    //   "path_lower": "/homework/lit/hamlet.xml",
    //   "path_display": "/Homework/lit/hamlet.xml",
    //   "id": "id:74FkdeNuyKAAAAAAAAAAAQ",
    //   "client_modified": "2016-06-02T23:19:00Z",
    //   "server_modified": "2016-06-02T23:19:00Z",
    //   "rev": "9482db15f",
    //   "size": 279658
    // }

    // Load the JSON, pretty-print it, and demonstrate how to get some values...
    Get Create (RefClass(cComChilkatJsonObject)) To hoJsonResult
    If (Not(IsComObjectCreated(hoJsonResult))) Begin
        Send CreateComObject of hoJsonResult
    End
    Set ComEmitCompact Of hoJsonResult To False
    Get ComLoad Of hoJsonResult sApiResult To iSuccess
    // Show the JSON pretty-printed...
    Get ComEmit Of hoJsonResult To sTemp1
    Showln sTemp1

    // Sample code to get data from the JSON response:
    Get ComIntOf Of hoJsonResult "size" To iSize
    Showln "size = " iSize

    Get ComStringOf Of hoJsonResult "rev" To sRev
    Showln "rev = " sRev

    Get ComStringOf Of hoJsonResult "client_modified" To sClientModified
    Get Create (RefClass(cComCkDateTime)) To hoCkdt
    If (Not(IsComObjectCreated(hoCkdt))) Begin
        Send CreateComObject of hoCkdt
    End
    Get ComSetFromTimestamp Of hoCkdt sClientModified To iSuccess
    Move True To iBLocalTime
    Get Create (RefClass(cComChilkatDtObj)) To hoDt
    If (Not(IsComObjectCreated(hoDt))) Begin
        Send CreateComObject of hoDt
    End
    Get pvComObject of hoDt to vDt
    Send ComToDtObj To hoCkdt iBLocalTime vDt

    Get ComDay Of hoDt To iTemp1
    Get ComMonth Of hoDt To iTemp2
    Get ComYear Of hoDt To iTemp3
    Get ComHour Of hoDt To iTemp4
    Get ComMinute Of hoDt To iTemp5
    Showln iTemp1 "/" iTemp2 "/" iTemp3 " " iTemp4 ":" iTemp5


End_Procedure