Uploading files

In order to upload files into a Servoy solution using a custom webcomponent here are the steps you should do :

• add a dataprovider type to the component spec, with 'pushToServer' support and 'ondatachange' callback:

  "file": {
      "type": "dataprovider",
      "pushToServer": "allow",
      "ondatachange": { "onchange": "onDataChangeMethodID", "callback": "onDataChangeCallback" }
  }

• add an  'ondatachange' handler to the component spec:

  "onDataChangeMethodID" : {
      "returns": "boolean", 
  
      "parameters": [
          {
              "name":"oldValue",
              "type":"${dataproviderType}"
          },
          {
              "name":"newValue",
              "type":"${dataproviderType}"
          },
          {
              "name":"event",
              "type":"JSEvent"
          }
      ]
  }

• add a 'multipart/form-data' 'form' element to the component markup, that will be used to post the files to the server;
  the action of the form must be :  "resources/upload/application_session_id/form_name/element_name/property_name", this can be build up in the component's controller code like : "resources/upload/" + $sabloApplication.getSessionId() + "/" + $scope.$parent.formname + "/" + $attrs.name + "/file" ("file" is the name of the dataprovider from the model):

  <form action="resources/upload/35400153-e5d3-41cb-8032-3b4f91459aca/test/fileupload/file" method="post" enctype="multipart/form-data"> 

• bind a form variable of type 'media' to the 'file' property of the component, let's say named 'm'; additionally create a form variable of type 'string' with name 'm_filename' and another of the same type named 'm_mimetype', that can be used to get the uploaded file name and mime type;
  
  
• 'ondatachange' of the component will be called with the uploaded file's byte array; if you also created the additional form variables for the file name and mime type, those are already set to the right values of the upload;