Retrofit download image

retrofit_download_image.kt

// Retrofit upload selected image
// https://futurestud.io/tutorials/retrofit-2-how-to-download-files-from-server
// https://viblo.asia/p/android-kotlin-retrofit-2-download-file-63vKjapx52R

// === Retrofit service ===
interface MediaService {

    @Streaming
    @GET
    suspend fun downloadImage(@Url fileUrl: String): ResponseBody
}


// === Repository ===
    val response = mediaService.downloadImage(fileUrl)
    writeResponseBodyToDisk(response)

    private fun writeResponseBodyToDisk(body: ResponseBody): Boolean {
        try {
            val tempFile = createImageFile()

            var inputStream: InputStream? = null
            var outputStream: OutputStream? = null

            try {
                val fileReader = ByteArray(4096)

                val fileSize = body.contentLength()
                var fileSizeDownloaded: Long = 0

                inputStream = body.byteStream()
                outputStream = FileOutputStream(tempFile)

                while (true) {
                    val read = inputStream.read(fileReader)

                    if (read == -1) {
                        break
                    }
                    outputStream.write(fileReader, 0, read)
                    fileSizeDownloaded += read.toLong()
                    Timber.tag(TAG).d("file download: $fileSizeDownloaded of $fileSize")
                }

                outputStream.flush()

                return true
            } catch (e: IOException) {
                return false
            } finally {
                inputStream?.close()
                outputStream?.close()
            }
        } catch (e: IOException) {
            return false
        }
    }

    @Throws(IOException::class)
    fun createImageFile(): File {
        // Create an image file name
        val timeStamp = getCurrentTimeString()
        val storageDir = context.getExternalFilesDir(Environment.DIRECTORY_PICTURES)

        return File.createTempFile(
            timeStamp, /* prefix */
            ".jpg", /* suffix */
            storageDir /* directory */
        )
    }

    private fun getCurrentTimeString() = SimpleDateFormat("yyyyMMdd_HHmmss").format(Date())