NameError in PostsController#create - ruby-on-rails

Question

So I'm working on a web app using rails and the google cloud datastore. I'm relatively new at coding web apps. Most of the errors I'm running into come from trying to integrate the datastore with the rails MVC model. For further context most of my code is based of the Google Datastore Bookshelf tutorial found on the datastore information page. https://cloud.google.com/ruby/getting-started/using-cloud-datastore
So recently I ran into a NameError in PostsController#create when I was trying to save a post to the datastore database. I can't seem to find the cause of this issue so hopefully someone can be my new set of eyes or provide some insight.
Also if you know any places where I can find helpful documentation using datastore and rails. That would be appreciated
So this is my post_controller.rb file
class PostsController < ApplicationController
PER_PAGE = 10
def index
#post, #cursor = Post.query limit: PER_PAGE, cursor: params[:cursor]
end
def new
#post = Post.new
end
def create
#post = Post.new post_params
if #post.save
flash[:success] = "Posted"
redirect_to posts_path(#post)
else
render :new
end
end
def edit
#post = Post.find(params[:id])
end
def update
#post = Post.find(params[:id])
if #post.update(post_params)
redirect_to #post
else
render 'edit'
end
end
def show
#post = Post.find(params[:id])
end
def destroy
#post = Post.find(params[:id])
#post.destroy
redirect_to posts_path
end
private
def post_params
params.require(:post).permit(:title, :body)
end
end
This is my model for the post post_rb
require "google/cloud/datastore"
class Post
include ActiveModel::Model
attr_accessor :title, :body
# Return a Google::Cloud::Datastore::Dataset for the configured dataset.
# The dataset is used to create, read, update, and delete entity objects.
def self.dataset
#dataset ||= Google::Cloud::Datastore.new(
project: Rails.application.config.
database_configuration[Rails.env]["dataset_id"]
)
end
# Query Book entities from Cloud Datastore.
#
# returns an array of Book query results and a cursor
# that can be used to query for additional results.
def self.query options = {}
query = Google::Cloud::Datastore::Query.new
query.kind "Post"
query.limit options[:limit] if options[:limit]
query.cursor options[:cursor] if options[:cursor]
results = dataset.run query
posts = results.map {|entity| Post.from_entity entity }
if options[:limit] && results.size == options[:limit]
next_cursor = results.cursor
end
return posts, next_cursor
end
# [START from_entity]
def self.from_entity entity
post = Post.new
post.id = entity.key.id
entity.properties.to_hash.each do |name, value|
post.send "#{name}=", value if post.respond_to? "#{name}="
end
post
end
# [END from_entity]
# [START find]
# Lookup Book by ID. Returns Book or nil.
def self.find id
query = Google::Cloud::Datastore::Key.new "Post", id.to_i
entities = dataset.lookup query
from_entity entities.first if entities.any?
end
# [END find]
# [START validations]
# Add Active Model validation support to Book class.
include ActiveModel::Validations
validates :title, presence: true
# [END validations]
# Save the book to Datastore.
# #return true if valid and saved successfully, otherwise false.
def save
if valid?
entity = to_entity
Post.dataset.save entity
self.id = entity.key.id
true
else
false
end
end
end
This is my new.html.erb file that i use to call the save method in datastore
<h1>Create Post</h1>
<%= form_for #post do |f| %>
<% if #post.errors.any? %>
<% #post.errors.full_messages.each do |msg| %>
<div class="alert alert danger"><%= msg %></div>
<% end %>
<% end %>
<div class="form-group">
<%= f.label:title %><br>
<%= f.text_field(:title, {:class => 'form-control'}) %>
</div>
<div class="form-group">
<%= f.label:body %><br>
<%= f.text_area(:body, {:class => 'form-control'}) %>
</div>
<p>
<%= f.submit({:class => 'btn btn-primary'}) %>
</p>
<% end %>
This is my routes.rb file
Rails.application.routes.draw do
get 'auth/:provider/callback', to: 'sessions#create'
get 'auth/failure', to: redirect('/')
get 'signout', to: 'sessions#destroy', as: 'signout'
resources :sessions, only: [:create, :destroy]
resource :main, only: [:show]
resources :posts
root to: 'posts#index', as: "home"
# For details on the DSL available within this file, see http://guides.rubyonrails.org/routing.html
end
EDIT: Forgot to include the error message log
NameError (undefined local variable or method `to_entity' for #<Post:0x65b0d70>
Did you mean? to_key):
app/models/post.rb:72:in `save'
app/controllers/posts_controller.rb:16:in `create'
NOTE: The create.html.erb is blank so I choose not to include it

Answer 1

Okay, it looks like you are missing a to_entity method. Try adding something similar to this for your post model. I slightly modified the code from the Book documentation example here. You will want to read that entire file to see what their Book model looks like with all of the code.
def to_entity
entity = Google::Cloud::Datastore::Entity.new
entity.key = Google::Cloud::Datastore::Key.new "Post", id
entity["title"] = title
entity["body"] = body
entity
end