Rails + Postgresql: data not saved first time - ruby-on-rails

The first time I try to submit the form I get the error saying
"Price is not a valid number"
It's OK the second time I try to submit it (with the same valid data in :price field).
If I don't add validation in the model, then the form is submitted, but value of price is not saved.
What could be going on? Is there something special about .decimal field?
db schema:
t.decimal "price"
model
validates :price, numericality: { :greater_than => 0, :less_than_or_equal_to => 100000000 }
form view file
<%= f.number_field :price, class: "short red" %>
controller
def new
#product = Product.new
end
def create
#product = Product.new(product_params)
if #product.save
redirect_to #product
else
render :new
end
end
private
def product_params
params.require(:product).permit(:name, :description, :image, :price, :user_id)
end
logs
Started POST "/products" for xxx.132 at 2014-10-15 22:56:51 +0000
Processing by ProductsController#create as HTML
Parameters: {"utf8"=>"✓",
"authenticity_token"=>"abte/LtO0T/ZtSXQIuXVVjjUvwHw5jDUJ1yIKCOWRx2=",
"product"=>{"name"=>"", "description"=>"", "user_id"
=>"1"}, "commit"=>"Submit"}

Some things you can check:
The snippet from your form starts f.number_field. Check that you are using something like <%= form_for(#product) do |f| %> at the top of the form.
Try to create a product using the rails console.
In the rails console, try something like this:
> p = Product.new
> p.valid?
#=> TRUE or FALSE should appear
> p.errors.full_messages.to_sentence
# you should see a full list of all failed validations from your Product model
If these don't help, try pasting in the entire product_controller.rb and _form.html.erb files into your question, and I'll take a look again.

Try to change your migration to:
t.decimal :price, precision: 8, scale: 2 #for example
Then, change validation to:
validates :price, numericality: {greater_than_or_equal_to: 0.01, :less_than_or_equal_to => 100000000 }
In PostgreSQL next implementations behavior with :decimal columns:
PostgreSQL: :precision [1..infinity], :scale [0..infinity]. No
default.
I hope, this example from "Agile Web Development with Rails 4" help you to understand validation of decimal numbers:
it’s possible to enter a number such as 0.001 into this field. Because
the database stores just two digits after the decimal point, this
would end up being zero in the database, even though it would pass the
validation if we compared against zero. Checking that the number is at
least 1 cent ensures only correct values end up being stored.

Related

activeadmin and dynamic store accessors fails on new resource

I want to generate forms for a resource that has a postgres jsonb column :data, and I want the schema for these forms to be stored in a table in the database. After a lot of research I am 90% there but my method fails in ActiveAdmin forms upon create (not update). Can anyone explain this?
Sorry for the long code snippets. This is a fairly elaborate setup but I think it would be of some interest since if this works one could build arbitrary new schemas dynamically without hard-coding.
I am following along this previous discussion with Rails 6 and ActiveAdmin 2.6.1 and ruby 2.6.5.
I want to store Json Schemas in a table SampleActionSchema that belong_to SampleAction (using the json-schema gem for validation)
class SampleActionSchema < ApplicationRecord
validates :category, uniqueness: { case_sensitive: false }, allow_nil: false, allow_blank: true
validate :schema_is_json_schema
private
def schema_is_json_schema
metaschema = JSON::Validator.validator_for_name("draft4").metaschema
unless JSON::Validator.validate(metaschema, schema)
errors.add :schema, 'not a compliant json schema'
end
end
end
class SampleAction < ActiveRecord::Base
belongs_to :sample
validate :is_sample_action
validates :name, uniqueness: { case_sensitive: false }
after_initialize :add_field_accessors
before_create :add_field_accessors
before_update :add_field_accessors
def add_store_accessor field_name
singleton_class.class_eval {store_accessor :data, field_name.to_sym}
end
def add_field_accessors
num_fields = schema_properties.try(:keys).try(:count) || 0
schema_properties.keys.each {|field_name| add_store_accessor field_name} if num_fields > 0
end
def schema_properties
schema_arr=SampleActionSchema.where(category: category)
if schema_arr.size>0
sc=schema_arr[0]
if !sc.schema.empty?
props=sc.schema["properties"]
else
props=[]
end
else
[]
end
end
private
def is_sample_action
sa=SampleActionSchema.where(category: category)
errors.add :category, 'not a known sample action' unless (sa.size>0)
errors.add :base, 'incorrect json format' unless (sa.size>0) && JSON::Validator.validate(sa[0].schema, data)
end
end
This all works correctly; For example, for a simple schema called category: "cleave", where :data looks like data: {quality: "good"}, I can create a resource as follows in the rails console:
sa=SampleAction.new(sample_id: 6, name: "test0", data: {}, category: "cleave" )
=> #<SampleAction id: nil, name: "test0", category: "cleave", data: {}, created_at: nil, updated_at: nil, sample_id: 6>
sa.quality = "good" => true
sa.save => true
To make this system work in AA forms, I call the normal path (new or edit)_admix_sample_action_form with params: {category: "cleave"} and then I generate permit_params dynamically:
ActiveAdmin.register SampleAction, namespace: :admix do
permit_params do
prms=[:name, :category, :data, :sample_id, :created_at, :updated_at]
#the first case is creating a new record (gets parameter from admix/sample_actions/new?category="xxx"
#the second case is updating an existing record
#falls back to blank (no extra parameters)
categ = #_params[:category] || (#_params[:sample_action][:category] if #_params[:sample_action]) || nil
cat=SampleActionSchema.where(category: categ)
if cat.size>0 && !cat[0].schema.empty?
cat[0].schema["properties"].each do |key, value|
prms+=[key.to_sym]
end
end
prms
end
form do |f|
f.semantic_errors
new=f.object.new_record?
cat=params[:category] || f.object.category
f.object.category=cat if cat && new
f.object.add_field_accessors if new
sas=SampleActionSchema.where(category: cat)
is_schema=(sas.size>0) && !sas[0].schema.empty?
if session[:active_sample]
f.object.sample_id=session[:active_sample]
end
f.inputs "Sample Action" do
f.input :sample_id
f.input :name
f.input :category
if !is_schema
f.input :data, as: :jsonb
else
f.object.schema_properties.each do |key, value|
f.input key.to_sym, as: :string
end
end
end
f.actions
end
Everything works fine if I am editing an existing resource (as created in the console above). The form is displayed and all the dynamic fields are updated upon submit. But when creating a new resource where e.g. :data is of the form data: {quality: "good"} I get
ActiveModel::UnknownAttributeError in Admix::SampleActionsController#create
unknown attribute 'quality' for SampleAction.
I have tried to both add_accessors in the form and to override the new command to add the accessors after initialize (these should not be needed because the ActiveRecord callback appears to do the job at the right time).
def new
build_resource
resource.add_field_accessors
new!
end
Somehow when the resource is created in the AA controller, it seems impossible to get the accessors stored even though it works fine in the console. Does anyone have a strategy to initialize the resource correctly?
SOLUTION:
I traced what AA was doing to figure out the minimum number of commands needed. It was necessary to add code to build_new_resource to ensure that any new resource AA built had the correct :category field, and once doing so, make the call to dynamically add the store_accessor keys to the newly built instance.
Now users can create their own original schemas and records that use them, without any further programming! I hope others find this useful, I certainly will.
There are a couple ugly solutions here, one is that adding the parameters to the active admin new route call is not expected by AA, but it still works. I guess this parameter could be passed in some other way, but quick and dirty does the job. The other is that I had to have the form generate a session variable to store what kind of schema was used, in order for the post-form-submission build to know, since pressing the "Create Move" button clears the params from the url.
The operations are as follows: for a model called Move with field :data that should be dynamically serialized into fields according to the json schema tables, both
admin/moves/new?category="cleave" and admin/moves/#/edit find the "cleave" schema from the schema table, and correctly create and populate a form with the serialized parameters. And, direct writes to the db
m=Move.new(category: "cleave") ==> true
m.update(name: "t2", quality: "fine") ==> true
work as expected. The schema table is defined as:
require "json-schema"
class SampleActionSchema < ApplicationRecord
validates :category, uniqueness: { case_sensitive: false }, allow_nil: false, allow_blank: true
validate :schema_is_json_schema
def self.schema_keys(categ)
sas=SampleActionSchema.find_by(category: categ)
schema_keys= sas.nil? ? [] : sas[:schema]["properties"].keys.map{|k| k.to_sym}
end
private
def schema_is_json_schema
metaschema = JSON::Validator.validator_for_name("draft4").metaschema
unless JSON::Validator.validate(metaschema, schema)
errors.add :schema, 'not a compliant json schema'
end
end
end
The Move table that employs this schema is:
class Move < ApplicationRecord
after_initialize :add_field_accessors
def add_field_accessors
if category!=""
keys=SampleActionSchema.schema_keys(category)
keys.each {|k| singleton_class.class_eval{store_accessor :data, k}}
end
end
end
Finally, the working controller:
ActiveAdmin.register Move do
permit_params do
#choice 1 is for new records, choice 2 is for editing existing
categ = #_params[:category] || (#_params[:move][:category] if #_params[:move]) || ""
keys=SampleActionSchema.schema_keys(categ)
prms = [:name, :data] + keys
end
form do |f|
new=f.object.new_record?
f.object.category=params[:category] if new
if new
session[:current_category]=params[:category]
f.object.add_field_accessors
else
session[:current_category] = ""
end
keys=SampleActionSchema.schema_keys(f.object.category)
f.inputs do
f.input :name
f.input :category
keys.each {|k| f.input k}
end
f.actions
end
controller do
def build_new_resource
r=super
r.assign_attributes(category: session[:current_category])
r.add_field_accessors
r
end
end
end

Money-Rails is discarding price amount after decimal point

I am building and Rails 5 API where I am trying to send money amount and store it in PostgresQL database. I am sending amount 2.4 but I see in database only 2 is stored. what I am doing wrong?
my migration:
class CreateTransactions < ActiveRecord::Migration[5.1]
def change
create_table :transactions do |t|
t.monetize :transaction_price, amount: { null: true, default: nil }
t.timestamps
end
end
end
my model is:
class Transaction < ApplicationRecord
monetize :transaction_price_cents
end
my controller:
class TransactionsController < ApiController
def create
transaction = Transaction.new(transaction_param)
if transaction.save
render json: { status: 'SUCCESS', data:transaction }, status: :ok
end
end
private
def transaction_param
params.require(:transaction).permit(:transaction_price_cents)
end
end
I am sending this json with postman:
{
"transaction_price_cents": 345.23
}
What I am getting in response:
{
"status": "SUCCESS",
"data": {
"id": 1,
"transaction_price_cents": 345,
"transaction_price_currency": "USD",
}
}
I either want 345.23 or 34523 but its giving me only 345!
Your price in cents! And that's ok!
Handling money in cents is a common pattern. It will also save your life when it comes to rounding errors with taxes or currency exchange. Like in their docs mentioned you should use a helper to output the price in a human readable form:
humanized_money #money_object # => 6.50
humanized_money_with_symbol #money_object # => $6.50
money_without_cents_and_with_symbol #money_object # => $6
If you accessing the data via an API you could add a human_readable field in your api
def transaction_price_human_readable
return humanized_money_with_symbol(#money_object) # or self or...
end
Save/Create model: If you get a floating number you could change the floating point into cents before_save
before_save :convert_transaction_price
def convert_transaction_price
self.transaction_price = (self.transaction_price * 100).to_i
end
I had the same problem.
(EDITED NEW AND CORRECT ANSWER):
All I had to do was to use the provided attribute from the money-rails gem. In my case I had an amount_cents attribute, and I had to use the provided :amount attribute in the form.
<%= f.label :amount %>
<%= f.text_field :amount %>
NOTE: I converted the value of :amount_cents to a float string in the edit.html.erb as followed:
<%= f.label :amount %>
<%= f.text_field :amount, value: number_with_precision(f.object.amount_cents / 100, precision: 2).gsub(/\./, ',') %>
(also note that I had configured money-rails to use EUROs which use "," as delimiter, thats why i have to use .gsbu(/\./, ','))
And here ist the IMPORTANT PART, I had to update my strong_parameters in the controller to permit :amount, and not :amount_cents
private
def invoice_params
params.require(:invoice).permit(…, :amount, …)
end
--
(OLD ANSWER):
I came to the conclusion that it is best to change the input value directly in the Frontend to cents. And then send the cents to the backend.
Here is a nice Stimulus Controller which does exactly that: https://gist.github.com/psergi/72f99b792a967525ffe2e319cf746101
(You may need to update that gist to your liking, and also it expects that you use Stimulus in your rails project)
(I leave the old answer in here, because I think it is a good practice to send _cents from the frontend to the backend, but in the moment it is not necessary [for me]. If you want to support more than one currency, you probably want to do it like that and use a .js framework to handle the input conversion -> s.th. like http://autonumeric.org/)

Save rails time_select as string

I have a string field in my databse
class CreateMHolidays < ActiveRecord::Migration
def change
create_table :m_holidays do |t|
t.string :open_schedule, :limit => 50
end
end
end
I am using time_select to get the value for open_schedule field.
<%= f.time_select :open_schedule, {minute_step: 01, include_blank: true,:default =>{:hour => '00', :minute => '00'},:ignore_date => true}, {:class => 'form-control'} %>
In my controller I try
#m_holidays = MHoliday.new(m_holiday_params)
#open_schedule_hrs = (params[:m_holidays]['open_schedule(4i)']).to_s
#open_schedule_mns = (params[:m_holidays]['open_schedule(5i)']).to_s
#m_holidays.open_schedule = #open_schedule_hrs + ':' + #open_schedule_mns
But when I try to save the record I am getting
ActiveRecord::MultiparameterAssignmentErrors (1 error(s) on assignment
of multiparameter attributes [error on assignment [3, 3] to
open_schedule (Missing Parameter - open_schedule(1))])
This is the first time I am using time_select and I must use it with a string field rather than :time. How to go about this? Any help much appreciated
You're getting the ActiveRecord::MultiparameterAssignmentErrors because of the mass parameter assignment on the line #m_holidays = MHoliday.new(m_holiday_params). This might be due to m_holiday_params containing parameters that your MHoliday model doesn't know what to do with.
Try filtering out everything related to the open_schedule input from m_holiday_params. If you have an m_holiday_params method like this:
def m_holiday_params
params.require(:m_holiday).permit('open_schedule(4i)', 'open_schedule(5i)', ...)
end
then omit the open_schedule parameters:
def m_holiday_params
params.require(:m_holiday).permit(...)
end
Then you can manually set up your open_schedule string, as you've already done.

Rails 4 enum validation

This is the first time I'm using enums with rails 4 and I ran into some issues, have couple of dirty solutions in mind and wanted to check are there any more elegant solutions in place :
This is my table migration relevant part:
create_table :shippings do |t|
t.column :status, :integer, default: 0
end
My model:
class Shipping < ActiveRecord::Base
enum status: { initial_status: 0, frozen: 1, processed: 2 }
end
And I have this bit in my view (using simple form for) :
= f.input :status, :as => :select, :collection => Shipping.statuses, :required => true, :prompt => 'Please select', label: false
So in my controller:
def create
#shipping = Shipping.create!(shipping_params)
if #shipping.new_record?
return render 'new'
end
flash[:success] = 'Shipping saved successfully'
redirect_to home_path
end
private
def shipping_params
params.require(:shipping).permit(... :status)
end
So when I submit create form and the create action fire I get this validation error :
'1' is not a valid status
So I thought I knew that the issue was data type so I added this bit in the model :
before_validation :set_status_type
def set_status_type
self.status = status.to_i
end
But this didn't seem to do anything, how do I resolve this ? Has anyone had the similar experience?
You can find the solution here.
Basically, you need to pass the string ('initial_status', 'frozen' or 'processed'), not the integer. In other words, your form needs to look like this:
<select ...><option value="frozen">frozen</option>...</select>
You can achieve this by doing statuses.keys in your form. Also (I believe) you don't need the before_validation.
Optionally, you could add a validation like this:
validates_inclusion_of :status, in: Shipping.statuses.keys
However, I'm not sure that this validation makes sense, since trying to assign an invalid value to status raises an ArgumentError (see this).

Rails: Virtual Attribute Reader Causing Error During Validations

Rails 3.0.3 application. . .
I'm using a virtual attribute in a model to convert a value stored in the database for display based on a user's preference (U.S. or metric units). I'm doing the conversion in the reader method, but when I test my presence validation I get a NoMethodError because the real attribute is nil. Here's the code:
class Weight < ActiveRecord::Base
belongs_to :user
validates :converted_weight, :numericality => {:greater_than_or_equal_to => 0.1}
before_save :convert_weight
attr_accessor :converted_weight
def converted_weight(attr)
self.weight_entry = attr
end
def converted_weight
unless self.user.nil?
if self.user.miles?
return (self.weight_entry * 2.2).round(1)
else
return self.weight_entry
end
else
return nil
end
end
...
This is the line that's causing the problem:
return (self.weight_entry * 2.2).round(1)
I understand why self.weight_entry is nil, but what's the best way to handle this? Should I just throw in an unless self.weight_entry.nil? check in the reader? Or should I perform this conversion somewhere else? (if yes, where?)
Thanks!
Here's what I've done:
Model
validates :weight_entry, :numericality => {:greater_than_or_equal_to => 0.1}
before_save :convert_weight
attr_reader :converted_weight
def converted_weight
unless self.user.nil?
unless self.weight_entry.nil?
if self.user.miles?
return (self.weight_entry * 2.2).round(1)
else
return self.weight_entry
end
end
else
return nil
end
end
Form
<%= f.label :weight_entry, 'Weight' %><br />
<%= f.text_field :weight_entry, :size => 8, :value => #weight.converted_weight %> <strong><%= weight_units %></strong> (<em>Is this not right? Go to your <%= link_to 'profile', edit_user_registration_path %> to change it</em>)
The unless.self.weight_entry.nil? check allows the validation to do it's job. If anyone knows of a better way to do this I'm open to suggestion.
Thanks!
P.S. The before_save convert_weight method converts U.S. units to metric. I want to store values in the same units consistently so if a user changes her preference later previously stored values don't become invalid.

Resources