When working with a form that includes input text fields and an input file field for database entries, I encountered an issue when creating a second form to edit the same entry. The data was retrieved from the database and filled into the new form, mirroring the fields of the original form. However, I ran into a problem with the file input field since I couldn't programmatically fill it in for security reasons.
This left the user to make edits as needed and update the entry. Yet, if the user chose not to change the file input field, my code would end up submitting the form with an empty file input, leading to a 400 (Bad request) error due to the Ajax request not being able to locate the servlet.
Here is a snippet of the code:
Within my Controller class:
@RequestMapping(value = RestUriConstants.SUBMETER, method = RequestMethod.POST)
public @ResponseBody JsonResponse submeter(@RequestPart("exercicio") final Exercicio exercicio,
@RequestPart("file") final MultipartFile file) {
...
}
And here is the Ajax request:
var exercicioObject = new Object();
exercicioObject.id = id;
exercicioObject.nome = nome;
exercicioObject.grupo = grupo;
var formData = new FormData();
formData.append("file", file.files[0]);
formData.append('exercicio', new Blob([JSON.stringify(exercicioObject)], {
type : "application/json"
}));
$.ajax({
url : '/Project/exercicio/submeter',
type : 'POST',
dataType : 'text',
data : formData,
processData : false,
contentType : false
});
In this scenario, I am setting a Json object to be passed to the server as an Exercicio object, while passing the file as a MultipartFile object. Despite not setting a MultipartFile object, Spring seems unable to find my URL that requires both parameters (Exercicio and MultipartFile). I'm uncertain how to pass anything to MultipartFile just to ensure Spring can correctly redirect my request to the appropriate server method.