Play framework CRUD file upload

2020-02-26 14:07发布

问题:

anyone know a way to add a file upload to Play's CRUD form? So far I have a view part like this:

   #{form action:@save(object._key()), enctype:'multipart/form-data'}
    #{crud.form}
        #{crud.custom 'file'}
            <label for="uploadFile">
                File
            </label>
            <input type="file" id="uploadFile" name="uploadFile" />
        #{/crud.custom}
    #{/crud.form}
    <p class="crudButtons">
        <input type="submit" name="_save" value="&{'crud.save', type.modelName}" />
        <input type="submit" name="_saveAndContinue" value="&{'crud.saveAndContinue', type.modelName}" />
    </p>
#{/form}

But I don't know how to write the controller method to handle the upload. And I don't want to store the file in the db as a blob, I wan't it on filesystem.

回答1:

This code will save your file into a "data/attachments" directory of your project:

Model

package models;

import play.db.jpa.Blob;
import play.db.jpa.Model;

import javax.persistence.Entity;

@Entity
public class MyApp extends Model {

   public String name;
   public Blob file;

}

Template

#{form action:@create(), enctype:'multipart/form-data'}
    #{crud.form /}

    <label for="uploadFile">File</label>
    <input type="file" id="uploadFile" name="myapp.file" />

    <p class="crudButtons">
        <input type="submit" name="_save"
            value="&{'crud.save', type.modelName}" />
        <input type="submit" name="_saveAndContinue"
            value="&{'crud.saveAndContinue', type.modelName}" />
    </p>
#{/form}

Controller

package controllers

import play.*;
import play.mvc.*;

import java.util.*;

import models.*;

/* Custom controller that extends
 * controller from CRUD module.
 */    
public class MyController extends CRUD {

    // ...

    // Will save your object
    public static void create(MyApp object) {

    /* Get the current type of controller and test it on non-empty */
    ObjectType type = ObjectType.get(getControllerClass());
    notFoundIfNull(type);

    /* We perform validation of the generated crud module form fields */
    validation.valid(object);
    if (validation.hasErrors()) {
        renderArgs.put("error", Messages.get("crud.hasErrors"));
        try {
            render(request.controller.replace(".", "/") + "/blank.html", type, object);
        } catch (TemplateNotFoundException e) {
            render("CRUD/blank.html", type, object);
        }
    }

    /* Save our object into db */
    object._save();

    /* Show messages */
    flash.success(Messages.get("crud.created", type.modelName));
    if (params.get("_save") != null) {
        redirect(request.controller + ".list");
    }
    if (params.get("_saveAndAddAnother") != null) {
        redirect(request.controller + ".blank");
    }

}

As stated above, you simply complements crud form by your own field and overrides crud method "create". The same can be done to update the record. You can change "data/attachments" directory in your application.conf:

application.conf

# ...
# Store path for Blob content
attachments.path=data/attachments
# ...

For more details see http://www.lunatech-research.com/playframework-file-upload-blob