(Swift 3,4,5...) Download File from Dropbox

Downloads a file from Dropbox.

Chilkat Downloads for the Swift Programming Language MAC OS X (Cocoa) Objective-C/Swift Libs iOS Objective-C/Swift Libs

func chilkatTest() {
    // 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.

    let rest = CkoRest()!

    // Connect to Dropbox
    var success: Bool = rest.connect("content.dropboxapi.com", port: 443, tls: true, autoReconnect: true)
    if success != true {
        print("\(rest.lastErrorText!)")
        return
    }

    // Add request headers.
    rest.addHeader("Authorization", value: "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": "/Homework/lit/hamlet.xml",
    // }

    let json = CkoJsonObject()!
    json.append("path", value: "/Homework/lit/hamlet.xml")
    rest.addHeader("Dropbox-API-Arg", value: json.emit())

    let bd = CkoBinData()!
    success = rest.fullRequestNoBodyBd("POST", uriPath: "/2/files/download", binData: bd)
    if success == false {
        print("\(rest.lastErrorText!)")
        return
    }

    // When successful, Dropbox responds with a 200 response code.
    if rest.responseStatusCode.intValue != 200 {
        // Examine the request/response to see what happened.
        print("response status code = \(rest.responseStatusCode.intValue)")
        print("response status text = \(rest.responseStatusText!)")
        print("response header: \(rest.responseHeader!)")
        print("response body (if any): \(bd.getString("utf-8")!)")
        print("---")
        print("LastRequestStartLine: \(rest.lastRequestStartLine!)")
        print("LastRequestHeader: \(rest.lastRequestHeader!)")
        return
    }

    // The file was downloaded into bd.
    // Save it to the filesystem.
    success = bd.writeFile("c:/temp/qa_output/hamlet.xml")

    // 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:
    var apiResult: String? = rest.responseHdr(byName: "dropbox-api-result")
    print("\(apiResult!)")

    // 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...
    let jsonResult = CkoJsonObject()!
    jsonResult.emitCompact = false
    jsonResult.load(apiResult)
    // Show the JSON pretty-printed...
    print("\(jsonResult.emit()!)")

    // Sample code to get data from the JSON response:
    var size: Int = jsonResult.int(of: "size").intValue
    print("size = \(size)")

    var rev: String? = jsonResult.string(of: "rev")
    print("rev = \(rev!)")

    var clientModified: String? = jsonResult.string(of: "client_modified")
    let ckdt = CkoDateTime()!
    ckdt.setFromTimestamp(clientModified)
    var bLocalTime: Bool = true
    var dt: CkoDtObj? = ckdt.getDtObj(bLocalTime)
    print("\(dt!.day.intValue)/\(dt!.month.intValue)/\(dt!.year.intValue) \(dt!.hour.intValue):\(dt!.minute.intValue)")
    dt = nil

}