How to open a PDF from WebView when PDF is secured by a cookie?-CodePudding

I am trying to download and open a PDF file from my WebView. I have tried retrieving the cookie from the WebView, and setting the cookie on a DownloadManager.Request. When my BroadCastReceiver is triggered, the download status states that it has failed.

this.webView?.apply {
            settings.domStorageEnabled = true
            settings.javaScriptEnabled = true

            setDownloadListener { url, _, _, mimetype, _ ->
                Log.w("downloading file", url)
                val downloadUri = Uri.parse(url)
                val downloadRequest = DownloadManager.Request(downloadUri).apply {
                    setTitle("Title")
                    setDescription("Downloading file")
                    Log.w("path", "${downloadUri.lastPathSegment}")
                    setDestinationInExternalFilesDir(context, Environment.DIRECTORY_DOWNLOADS, downloadUri.lastPathSegment)
                    val cookie = getCookie("https://www.example.com", "example_cookie_name")
                    Log.w("cookie", "${cookie}")
                    addRequestHeader("Cookie", cookie)
                }

                val manager: DownloadManager = getSystemService(Context.DOWNLOAD_SERVICE) as DownloadManager
                val downloadId = manager.enqueue(downloadRequest)

                registerReceiver(
                    object: BroadcastReceiver() {
                        override fun onReceive(context: Context?, intent: Intent?) {
                            Log.w("onReceive", "${intent?.action}")
                            if (intent !== null && DownloadManager.ACTION_DOWNLOAD_COMPLETE == intent.action) {
                                val cursor = manager.query(DownloadManager.Query().apply{ setFilterById(downloadId) })

                                if (cursor.moveToFirst()) {
                                    Log.w("onReceive", "cursor moved")
                                    val downloadStatus = cursor.getInt(cursor.getColumnIndex(DownloadManager.COLUMN_STATUS))
                                    val downloadLocalUri = cursor.getString(cursor.getColumnIndex(DownloadManager.COLUMN_LOCAL_URI))
                                    val downloadMimeType = cursor.getString(cursor.getColumnIndex(DownloadManager.COLUMN_MEDIA_TYPE))
                                    Log.w("onReceive", "$downloadStatus $downloadLocalUri $downloadMimeType")
                                    if (downloadStatus == DownloadManager.STATUS_SUCCESSFUL && downloadLocalUri !== null) {
                                        val viewIntent = Intent(Intent.ACTION_VIEW).apply {
                                            this.setDataAndType(Uri.parse(downloadLocalUri), downloadMimeType)
                                        }
                                        if (viewIntent.resolveActivity(packageManager) !== null) {
                                            startActivity(
                                                Intent.createChooser(viewIntent, "Choose app")
                                            )
                                        } else {
                                            Toast.makeText(
                                                context,
                                                "No app available that can open file",
                                                Toast.LENGTH_SHORT
                                            )
                                                .show()
                                        }
                                    }
                                }


                            }
                        }
                    },
                    IntentFilter(DownloadManager.ACTION_DOWNLOAD_COMPLETE)
                )
            }
}

Through the logging in this code, I can confirm that I am getting the cookie out of the WebView.

Is there a better approach to handle this? If not, how do I determine why the download is failing? Also, what am I doing wrong?

Ideally, I would also be able to download the file, and ensure it is deleted after the user has finished viewing the PDF.

CodePudding user response：

You could try something like this before loading the webview's content.

fun setCookies() {
       val cookieManager = CookieManager.getInstance()
       val cookieString = "your_cookie_here"
       cookieManager.setCookie("domain_name_of_the_dowload_url", cookieString)
       cookieManager.setAcceptThirdPartyCookies(your_webview_here, true)
}

CodePudding user response：

It turned out that the way I was retrieving the cookie was wrong, it ended up stripping out the key. For future reference, it is quite simple to set the cookie on the download request, with:

addRequestHeader("Cookie", CookieManager.getInstance().getCookie(url))