model view controller - Spring MVC: parameter 'promotion' is not present

Question

My goal is to load a "Promotion" object into an HTML form, modify some of the inputs, click "save" and save the changes to that Promotion object back to a database. The first part is woriking, I can see the form and the inputs are loaded with the appropriate values. However, when I click "save", I get the following error:

PromotionRequest parameter 'promotion' is not present

Here's my controller code:

    @RequestMapping ( value = "", method = RequestMethod.GET, produces = { MediaType.TEXT_HTML_VALUE } )
    public String getEditCampaignPage( final Model model,
                                          @RequestParam ( value = "campaignId" ) final int campaignIdParam )
    {
        String token = securityService.getCurrentUser().getTokenId();


        int campaignId = campaignIdParam;
        Promotion original = promotionService.obtain(token, campaignId);
        model.addAttribute("campaignId" , campaignId);
        model.addAttribute("promotion", original);

        return "marketing.campaigns.edit.campaign.edit-campaign.definition";
    }

    @RequestMapping ( value = "submit", method = RequestMethod.POST, produces = { MediaType.TEXT_HTML_VALUE } )
    public String getSubmitCampaignPage( final Model model,
                                         final HttpServletRequest request,
                                         @RequestParam ( value = "campaignId" ) final long campaignId,
                                         @RequestParam (value = "promotion") final Promotion campaign,
                                         final BindingResult result,
                                         final RedirectAttributes redirectAttributes )
    {
        final int partnerId = securityService.getCurrentUser().getPartnerId();


        //TODO: Save the modified campaign and return to an edit or view screen for that campaign

        return "marketing.campaigns.edit.campaign.edit-campaign.definition";
    }

question from:https://stackoverflow.com/questions/65945076/spring-mvc-parameter-promotion-is-not-present

Answer 1

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