Rails - update/edit check if record exists from controller

Question

I used this page to help me validate if adding a new entry (add a new exercise in my case) which worked great Check if record exists from controller in Rails

But I can't quite seem to get it to work if I'm updating/editing an exercise.

In plain English I'm trying to:

Get current exercise record the user wants to edit(done), user updates the values(done), submits(done), the controller checks the user's input against the db to see if a record already exists with the same name, if it exists error, if not, update.

Thanks.

Here's the part of my controller that I can't quite get going for update:

class ExercisesController < ApplicationController
  before_action :authenticate_user!, :except => [:index, :show]
  before_filter :set_exercise, only: [:show, :edit, :update, :destroy, :upvote, :downvote]

    def new
    @exercise = Exercise.new
  end

  def create
    @exercise = current_user.exercises.build(exercise_params)
    if Exercise.exists?(name: @exercise.name)
      flash.now[:danger] = "Exercise has not been created, duplicate entry"
      render :new
    elsif @exercise.save
      flash[:success] = "Exercise has been created"
      redirect_to exercises_path
    else
      flash.now[:danger] = "Exercise has not been created"
      render :new
    end
  end

  def edit
    if !current_user.admin?
      flash[:danger] = "You are not an admin"
      redirect_to root_path
    end
  end 

  def update
    if !current_user.admin?
      flash[:danger] = "You are not an admin"
      redirect_to root_path
    else
      if Exercise.where(:name => @exercise.name).any?
        flash.now[:danger] = "Exercise has not been updated, duplicate entry"
        render :edit
      elsif @exercise.update(exercise_params)
        flash[:success] = "Exercise has been updated"
        redirect_to @exercise
      else
        flash.now[:danger] = "Exercise has not been updated"
        render :edit
      end
    end
  end

private 
    def exercise_params
      params.require(:exercise).permit(:name, :description, :summary)
    end

    def set_exercise
      @exercise=Exercise.find(params[:id])
    end

DB searching is case sensitive. Thus Exercise.where(:name => @exercise.name).any? will always return false if the name has distinct upper/lower cases — Cristiano Mendonça, Apr 30 '16 at 15:14
The part that's not working is my logic in the if statement - I can't get the controller to compare the user's input with other exercise names in the table like i did in create, it either always comes back saying duplicate entry (when there isn't) or allows me to make the change and there is something already has the exact same name. @CristianoAlencar, good to know about the upper/lowercase, if this is the case, what if statement would work as each exercise name starts with an uppercase - eg Cycling — Adam First, Apr 30 '16 at 22:25

score 1 · Answer 1 · answered May 01 '16 at 12:01

Found an easier way to make this work. In the model you can specify uniqueness.

 class Exercise < ActiveRecord::Base 
  validates :name, presence: true, :uniqueness => true

so my model looks like this for update:

 def update
    if !current_user.admin?
      flash[:danger] = "You are not an admin"
      redirect_to root_path
    else
      if @exercise.update(exercise_params)
        flash[:success] = "Exercise has been updated"
        redirect_to @exercise
      else
        flash.now[:danger] = "Exercise has not been updated"
        render :edit
      end
    end
  end

Rails - update/edit check if record exists from controller

1 Answers1