MissingServletRequestParameterException

Question

I'm passing a formData object to my Spring back-end:

imageBanner(banner: File, bannerPath: string, id: number, callback: (response) => void){
    var formData = new FormData();
    formData.append('name', banner.name);
    console.log(formData.get('name'));
    formData.append('file', banner);
    console.log(formData.get('file'));

    this.sendPost("/upload/" + bannerPath, formData, response => {
        callback(response);
    });

}

The console log shows:

1.jpg 
File {name: "1.jpg", lastModified: 1496737372408, lastModifiedDate: Tue Jun 06 2017 10:22:52 GMT+0200 (W. Europe Daylight Time), webkitRelativePath: "", size: 38983…}

So it looks like the formData has some values.

In the back-end I have this:

@RequestMapping(value="/rest/upload/localeventbanner", method=RequestMethod.POST, headers = "content-type!=multipart/form-data")
    public @ResponseBody String uploadFileHandler(@RequestParam("name") String name, @RequestParam("file") MultipartFile file) {

    if (!file.isEmpty()) {
        try {
            log("success");

            return "You successfully uploaded file=" + name;
        } catch (Exception e) {
            log("fail");
            return "You failed to upload";
        }
    } else {
        log("nope");
        return "You failed to upload " + name
                + " because the file was empty.";
    }
}

The return I'm getting in the console is:

"{"timestamp":1502745177167,"status":400,"error":"Bad Request","exception":"org.springframework.web.bind.MissingServletRequestParameterException","message":"Required String parameter 'name' is not present","path":"/beheerback/rest/upload/localeventbanner"}"

It says name isn't present but when I log it in the front-end it shows name is present in the formData object.

Answer 1

Try to give required = false for name and file, something like:

@RequestParam(value = "name", required = false, defaultValue = "defaultName") String name, @RequestParam(value = "file" , required = false, defaultValue = "defaultFile") MultipartFile file

Then check the values that you're really getting. Also, check the form sent using the network inspector in the dev mode of your browser.