I'm having an issue where I have a form that will save all updates to a formula. This loads fine and everything works except for when trying to delete an ingredient within a list that is in the updateFormula object.

When I pass my two @RequestParameters in to delete a specific ingredient, I recieve the error:

Required request parameter 'formulaId' for method parameter type String is not present

This has stumped me as the formulaId parameter is for the first @GetMapping method updateFormula, which retrieves the formula information that can be updated. I have tried adding the formulaId as a model object, and pass that into the deleteIngredientInFormula method, but that did not work either.

@GetMapping to get all formula details to display

 @GetMapping("/update-formula")
    public String updateFormula(@RequestParam("formulaId") String id, Model model) {
        //unwraps the optional formula object if present, then adds to the model.
        formulaService.getFormulaById(id).ifPresent(f -> model.addAttribute("updatedFormula",f));
        return "Update-Formula-Form";
    }

@GetMapping to select a specific ingredient in the list to delete

    @GetMapping("delete-ingredient")
    public String deleteIngredientInFormula(@RequestParam("ingredientId") String inId,
                                            @RequestParam("formId") String formId) {

        formulaService.deleteIngredientInFormula(formId, inId);
        return "redirect:/update-formula";
    }

Thymeleaf Page: Update-Formula-Form

<div class="container">
    <h2>Formula Update Form</h2>
    <form action="#" th:action="@{/save-updated-formula}" method="post" th:object="${updatedFormula}">

      <input type="text" th:readonly="true" th:field="*{formulaId}">
      <input type="text" th:field="*{formulaName}">
      <input type="text" th:field="*{dosageForm}">
      <input type="text" th:readonly="true" th:field="*{unitWeight}">
      <input type="text" th:field="*{servingSize}">

  <!--FORMULA INGREDIENTS (SELECT ACTION) -->
    <div class="container table-responsive">
      <table class="table table-striped">
        <thead class="table-light">
        <tr>
          <td>Ingredient ID</td>
          <td>Ingredient Name</td>
          <td>Type</td>
          <td>Potency</td>
          <td>Manufacturer</td>
          <td>Label Claim (mg)</td>
          <td>Delete Ingredient</td>
        </tr>
        </thead>
        <tbody>
        <tr th:each="ingredient, holder : *{ingredients}">
          <td><input th:readonly="true" th:field="*{ingredients[__${holder.index}__].ingredientId}"></td>
          <td><input th:readonly="true" th:field="*{ingredients[__${holder.index}__].ingredientName}"></td>
          <td><input th:readonly="true" th:field="*{ingredients[__${holder.index}__].type}"></td>
          <td><input th:field="*{ingredients[__${holder.index}__].potency}"></td>
          <td><input th:readonly="true" th:field="*{ingredients[__${holder.index}__].manufacturer}"></td>
          <td><input th:field="*{ingredients[__${holder.index}__].labelClaim}"></td>
          <td>
            <a th:href="@{/delete-ingredient(ingredientId=${ingredient.getIngredientId()}, formId=${updatedFormula.getFormulaId()})}"
               class="btn btn-info btn-sm">Delete</a>
          </td>
        </tr>
        </tbody>
      </table>
    </div>

      <button type="submit" class="btn btn-info col-2">Save Formula Details</button>
    </form>
</div>

CodePudding user response：

When you call the @GetMapping("delete-ingredient") endpoint you are then redirecting to update-formula which requires formulaId. That is why you are getting the error. You are basically redirecting to update-formula without any additional data. You need to add that as follows:

@GetMapping("delete-ingredient")
public String deleteIngredientInFormula(@RequestParam("ingredientId") String inId,
                                        @RequestParam("formId") String formId) {
    formulaService.deleteIngredientInFormula(formId, inId);
    return "redirect:/update-formula?formulaId="   formId;
}

Additionally, you might want to use the same parameter names for the same thing. You have @RequestParam("formulaId") String id and @RequestParam("formId") String formId which if I understood this correctly are one and the same thing formulaId.

Finally, you definitely shouldn't use a GET to delete data. That is why the DELETE HTTP method exists.