How to save to a file system directory in Grails - grails

Question

I am trying to save an uploaded file into the file system directory, and allow other users to download it.
I am currently saving it in my database and not in my file system directory. Here is my code:
class Document {
String filename
byte[] filedata
Date uploadDate = new Date()
static constraints = {
filename(blank: false, nullable:false)
filedata(blank: true, nullable: true, maxSize:1073741824)
}
}
and my controller for uploading the file is:
class DocumentController {
static allowedMethods = [delete: "POST"]
def index = {
redirect(action: "list", params: params)
}
def list() {
params.max = 10
[documentInstanceList: Document.list(params), documentInstanceTotal: Document.count()]
}
def uploadPage() {
}
def upload() {
def file = request.getFile('file')
if(file.isEmpty())
{
flash.message = "File cannot be empty"
}
else
{
def documentInstance = new Document()
documentInstance.filename = file.getOriginalFilename()
documentInstance.filedata = file.getBytes()
documentInstance.save()
}
redirect (action: 'list')
}
}

Answer 1

I think you could do a fuction similar to the one below:
boolean upload(MultipartFile uploadFile, String fileUploadDir){
String uploadDir = !fileUploadDir.equals('') ?: 'C:/temp' //You define the path where the file will be saved
File newFile = new File("$uploadDir/${uploadFile.originalFilename}"); //You create the destination file
uploadFile.transferTo(newFile); //Transfer the data
/**You would need to create an independent Domain where to store the path of the file or have the path directly in your domain*/
}
Since you will only need to save the path of the file you could add a string to your domain to store it or you could create an independent domain to store the data of your file. You will also need to add try/catch statements where needed.
And to retrieve the file you would need to add to your controller something like the next code:
File downloadFile = new File(yourFileDomain?.pathProperty) //get the file using the data you saved in your domain
if(downloadFile){ //Set your response properties
response.characterEncoding = "UTF-8"
response.setHeader "Content-disposition", "attachment; filename=\"${yourFileDomain?.fileNameProperty}\"" //add the header with the filename you saved in your domain you could also set a default filename
//response.setHeader "Content-disposition", "attachment; filename=\"myfile.txt\""
response.outputStream << new FileInputStream(downloadFile)
response.outputStream.flush()
return
}
Hope this helps, any comments are welcome.