Rails saving german price to database - ruby-on-rails

i want to save a price like this "199,99" as a float or decimal to the database.
i have tried to replace the "," with "." in the model with a before filter.
but the price is passed to the before filter as "199.00".
is there a way to convert that in the model class?
I know how to do this in the controller, but how can i do it in the model?
thanks for your help.

I believe the correct way of doing this is keep the db value as it is, and in your view layer create a helper method to display the amount with your preferred formatting
so basic idea is, in your application helper
module ApplicationHelper
#p for price, just to keep things simple
def p(amount)
amount.gsub(".",",")
end
end
and in your view
<%= p(object.price) %>
and one more disadvantage of your approach is , if you save the price as 123,34, you will not be able to do any calculations later.
HTH

You should use number_to_currency helper and appropriate locales
Or if you don't want to mess with locales declare separator explicitly.
number_to_currency(value_from_db, :unit => "$;", :separator => ".", :delimiter => " ", :format => "%u %n")

Related

Getting Globalize and autocomplete to work together

Using globalize gem to manage translations with autocomplete, there is a situation where a number of hooks need to be properly set. Note: this does not use hstore AFAIK. I have not managed to find a way to do so. The most productive set-up to date has
controller:
autocomplete :nation, :name, :full => true
Nation
translates :name
view
<%= autocomplete_field_tag 'nation_name', '', autocomplete_nation_name_itins_path, size: 35, :id_element => 'nation_id' %>
There is no inherent reference to nation_translations database table created by Globalize as of yet. As this image suggests, there is a problem:
Issue 1: The input remains binded to the base table's attribute value (I have not yet cleared them out as the Globalize gem suggests. Otherwise I'd be getting blanks). can is actually ready all values of canin master table... Typing in other locales, like cyrillic say Канада has naturally no effect as that value is not part of the Nation table.
What is interesting is that the drop-down values are being populated by Rails automatically, extracting the translation values of what is input.
Issue 2: I'd rather pass the parameter 'nation_id' which is naturally part of the nation_translations table with the form data. although I can append , :extra_data => [:nation_id] to the controller it is not being submitted (example in cyrillic where the input is given without any autocomplete)
{"utf8"=>"✓", "nation_name"=>"Канада", "commit"=>"..."}
Rails.logger.info :extra_data returns:
extra_data
Now the second issue can be overcome because a query like
Nation::Translation.where('name = ?', "Канада").pluck('nation_id')
returns a proper result. But that point is moot if the autocomplete is not playing ball with the user's input.
How can this be configured to have user input autocomplete with the current local translations?
this does get solved by creating an entirely new class with attributes nation_id, name, locale and can thus be called symbolically.
The query call is not that straightforward however. As the gem suggests, the method need to be tweaked
def autocomplete_nation_name
term = params[:term].downcase
locale = params[:locale]
nationtranslations = Nationtranslation.where('locale = ? AND name LIKE ?', locale, "%#{term}%").order(:name).all
render :json => nationtranslations.map { |nationtranslation| {:id => nationtranslation.id, :label => nationtranslation.name, :value => nationetranslation.name} }
end
intervening on the action method itself provides all the leeway desired...

Formatting credit card number in a number_field_tag [duplicate]

I would like to make editing form fields as user-friendly as possible. For example, for numeric values, I would like the field to be displayed with commas (like number_with_precision).
This is easy enough on the display side, but what about editing? Is there a good way to do this?
I am using the Rails FormBuilder. Upon investigation, I found that it uses InstanceTag, which gets the values for fields by using <attribute>_value_before_type_cast which means overriding <attribute> won't get called.
The best I have come up with so far is something like this:
<%= f.text_field :my_attribute, :value => number_with_precision(f.object.my_attribute) %>
Or my_attribute could return the formatted value, like this:
def my_attribute
ApplicationController.helpers.number_with_precision(read_attribute(:my_attribute))
end
But you still have to use :value
<%= f.text_field :my_attribute, :value => f.object.my_attribute %>
This seems like a lot of work.
I prefer your first answer, with the formatting being done in the view. However, if you want to perform the formatting in the model, you can use wrapper methods for the getter and setter, and avoid having to use the :value option entirely.
You'd end up with something like this.
def my_attribute_string
foo_formatter(myattribute)
end
def my_attribute_string=(s)
# Parse "s" or do whatever you need to with it, then set your real attribute.
end
<%= f.text_field :my_attribute_string %>
Railscasts covered this with a Time object in a text_field in episode #32. The really clever part of this is how they handle validation errors. It's worth watching the episode for that alone.
This is an old question, but in case anyone comes across this you could use the number_to_X helpers. They have all of the attributes you could ever want for displaying your edit value:
<%= f.text_field :my_number, :value => number_to_human(f.object.my_number, :separator => '', :unit => '', :delimiter => '', :precision => 0) %>
There are more attributes available too: http://api.rubyonrails.org/classes/ActionView/Helpers/NumberHelper.html
If you want a format to be created or maintained during editing, you will need to add Javascript to implement "masks." Here is a demo.
It was the first hit in these results.
You can use the number_format plugin. By specifying a number_format for an existing numeric attribute inside your model, the attribute will now appear as formatted to Rails in all forms and views. It will also be parsed back from that format (when assigned via forms) prior to insertion into the database. (The plugin also creates purely numeric unformatted_<attribute-name> accessors which can continue to be used for arithmetic, or for direct numerical assignment or retrieval by you for seamless integration.)
class MyModel < ActiveRecord::Base
# this model has the balance attribute, which we
# want to display using formatting in views,
# although it is stored as a numeric in the database
number_format :balance,
:precision => 2,
:delimiter => ',',
:strip_trailing_zeros => false
def increment_balance
unformatted_balance += 10
end
You can also combine the above with a Javascript solution, which can force the user to maintain the decimal point and thousands separators in place while editing, although this is really not necessary.
I have done something similar. We format times and lengths using a custom form builder. It makes use of the existing text_field, but wraps it so the value can be customized:
class SuperFormBuilder < ActionView::Helpers::FormBuilder
include ApplicationHelper
include FormHelper
include ActionView::Helpers::TagHelper
include ActionView::Helpers::FormTagHelper
def length_field(label,*args)
scale = 'medium'
args.each do |v|
if v.has_key?(:scale)
scale = v[:scale]
v.delete(:scale)
end
end
value = length_conversion(#object.send(label.to_sym),scale)
options = (args.length > 0) ? args.pop : {}
return has_error(label, text_field_tag(field_name(label),value,*args) + ' ' + length_unit(scale))
end
private
def field_name(label)
return #object_name + "[#{label}]"
end
def has_error(label, output)
return "<div class='fieldWithErrors'>#{output}</div>" if #object.errors[label]
return output
end
And it is used like this:
<%= form_for( #section, {:action => 'save', :id => #section.id}, :builder => SuperFormBuilder) do |sf| %>
<%= sf.length_field :feed_size_min_w, :size => 3, :scale => 'small' %>
<% end %>
The end result is a value in the appropriate unit based off their choice on system (Metric, Imperial) and scale IE small = inches or millimeters.
I basically copied the text_field method from the existing form builder, which uses the text_field_tag itself.
There are two gotchas: 1) Knowing the name of the object field and how to access the object to get the value which you want to format. 2) Getting the name right so when the form is submitted it is part of the correct params hash.
The form builder is given a class variable #object. You can get the value of the field using the .send method. In my case I send the label :feed_size_min_w to the #object and get its length back. I then convert it to my desired format, and give it to the text_field_tag.
The name of the field is key to having it end up in the params hash, in my instance the params[:sections] one. I made a little helper function called field_name that takes care of this.
Finally the has_error wraps the field in an error div if there are errors on that label.
I needed "nicer" format on some specified text fields, resolved it by adding this to my initializers. Seems to work nicely on Rails ~= 5.2 and it should be easy to customize.
class ActionView::Helpers::Tags::TextField
private
def value_before_type_cast # override method in ActionView::Helpers::Tags::Base
v = super
# format as you like, when you like
if #options.delete(:nice_decimal)
v = v.to_s.gsub('.', ',') if v.is_a?(BigDecimal)
end
v
end
end
Usage in form f
<%= f.text_field :foo, nice_decimal: true %>

haml and ruby on rails date of birth date field syntax

SO I have been learning ror and trying out some form examples.
Most of the examples in the web is in erb format and my files are in .haml format. I am trying to a write a static dob field where it takes day,time,year.
view
%label{:for => "patient_dob"} DOB
%date_select {Date.today,start_year => getBirthDateStart(), :end_year => getBirthDateEnd() }
module ApplicationHelper
def getBirthDateStart()
Time.now.year - 100
end
def getBirthDateEnd()
Time.now.year
end
end
I know my code doesn't make much sense, but hope it explains what I am trying to do. Can someone point me to the correct direction.
"%date_select" is not an HTML element. You'll use "%" to create things like %title, %p
You'll want to use "%" to create HTML directly. In this case, you'd use "%select"% to create s select box. In Ruby on Rails, you have form helper that you'll call to create collections like this.
=label_tag "patient_dob", "DOB"
=date_select "patient", "dob", { start_year: 100.years.ago.year, end_year: Date.today.year, default: Date.today}
Docs: http://apidock.com/rails/ActionView/Helpers/DateHelper/date_select
In Haml, you use % to start a tag, and = to use a helper method like date_select. You could rewrite your example like this:
=label_tag :patient_dob, "DOB"
=date_select :patient, :dob, :start_year => 5.years.ago, :end_year => 5.years.from_now
A few other things:
In Ruby, using camelCase method names (like getBirthStartYear) is unconventional. Stick with snake_case, and your code will be consistent with the rest of Rails and the Ruby community.
It's also a good idea to drop the parenthesis () from method calls as well. This helps blur the line behind what is a property and what is a method, which I think encourages better internal API design. For that reason, I would also encourage you to drop the get in favour of something more meaningful, like new_patient_dob_start_year.
Honestly, though, for the sake of simplicity and clarity, I would avoid making additional methods if there's no reason to. 5.years.ago or 5.years.from_now is very easy to read, and doesn't require another programmer looking up where a method is defined.

String concatenation not possible?

So over the last 2 hours, I've been trying to fill a combobox with all my users. I managed to get all firstnames in a combobox, but I want their full name in the combobox. No problem you would think, just concatenate the names and you're done. + and << should be the concatenation operator to do this.So this is my code:
<%= collection_select(:user, :user_id, #users, :user_id, :user_firstname + :user_lastname, {:prompt => false}) %>
But it seems RoR doesn't accept this:
undefined method `+' for :user_firstname:Symbol
What am I doing wrong?
What you need to do is define a method on the User model that does this concatenation for you. Symbols can't be concatenated. So to your user model, add this function:
def name
"#{self.first_name} #{self.last_name}"
end
then change the code in the view to this:
<%= collection_select(:user, :user_id, #users, :user_id, :name, {:prompt => false}) %>
Should do the trick.
This isn't really rails giving you an error, it's ruby. You're trying to combine the symbols :user_firstname and :user_lastname
A symbol is a variable type, just like integer, string, or datetime (Well technically they're classes, but in this context we can think of them as variable types). They look similar to strings, and can function similarly to them, but there is no definition for the behavior of symbol concatenation. Essentially you're trying to send the method user_firstnameuser_lastname which is just as non-sensical as trying to concat two Symbols.
What you need to understand is that this parameter is looking for a method on your User object, and it won't understand the combination of two symbols. You need to define a method in your model:
def fullname
[user_firstname, user_lastname].reject{|v| v.blank?}.join(" ")
end
This'll return your first + last name for you, and then in the parameter you should send :fullname (because that's the method it'll call on each user object in the collection):
<%= collection_select(:user, :user_id, #users, :user_id, :fullname, {:prompt => false})%>
Also, it's considered poor practice to prefix every single column with the table name. user.user_firstname just looks redundant. I prefer to drop that prefix, but I guess it's mostly up to personal preference.
The arguments for value and display attribute are method names, not expressions on a user object.
To control the format more precisely, you can use the select tag helper instead:
select("user", "user_id", #users.each {|u| [ "#{u.first_name u.last_name}", u.user_id ] })
The docs are pretty useful.

How can I format the value shown in a Rails edit field?

I would like to make editing form fields as user-friendly as possible. For example, for numeric values, I would like the field to be displayed with commas (like number_with_precision).
This is easy enough on the display side, but what about editing? Is there a good way to do this?
I am using the Rails FormBuilder. Upon investigation, I found that it uses InstanceTag, which gets the values for fields by using <attribute>_value_before_type_cast which means overriding <attribute> won't get called.
The best I have come up with so far is something like this:
<%= f.text_field :my_attribute, :value => number_with_precision(f.object.my_attribute) %>
Or my_attribute could return the formatted value, like this:
def my_attribute
ApplicationController.helpers.number_with_precision(read_attribute(:my_attribute))
end
But you still have to use :value
<%= f.text_field :my_attribute, :value => f.object.my_attribute %>
This seems like a lot of work.
I prefer your first answer, with the formatting being done in the view. However, if you want to perform the formatting in the model, you can use wrapper methods for the getter and setter, and avoid having to use the :value option entirely.
You'd end up with something like this.
def my_attribute_string
foo_formatter(myattribute)
end
def my_attribute_string=(s)
# Parse "s" or do whatever you need to with it, then set your real attribute.
end
<%= f.text_field :my_attribute_string %>
Railscasts covered this with a Time object in a text_field in episode #32. The really clever part of this is how they handle validation errors. It's worth watching the episode for that alone.
This is an old question, but in case anyone comes across this you could use the number_to_X helpers. They have all of the attributes you could ever want for displaying your edit value:
<%= f.text_field :my_number, :value => number_to_human(f.object.my_number, :separator => '', :unit => '', :delimiter => '', :precision => 0) %>
There are more attributes available too: http://api.rubyonrails.org/classes/ActionView/Helpers/NumberHelper.html
If you want a format to be created or maintained during editing, you will need to add Javascript to implement "masks." Here is a demo.
It was the first hit in these results.
You can use the number_format plugin. By specifying a number_format for an existing numeric attribute inside your model, the attribute will now appear as formatted to Rails in all forms and views. It will also be parsed back from that format (when assigned via forms) prior to insertion into the database. (The plugin also creates purely numeric unformatted_<attribute-name> accessors which can continue to be used for arithmetic, or for direct numerical assignment or retrieval by you for seamless integration.)
class MyModel < ActiveRecord::Base
# this model has the balance attribute, which we
# want to display using formatting in views,
# although it is stored as a numeric in the database
number_format :balance,
:precision => 2,
:delimiter => ',',
:strip_trailing_zeros => false
def increment_balance
unformatted_balance += 10
end
You can also combine the above with a Javascript solution, which can force the user to maintain the decimal point and thousands separators in place while editing, although this is really not necessary.
I have done something similar. We format times and lengths using a custom form builder. It makes use of the existing text_field, but wraps it so the value can be customized:
class SuperFormBuilder < ActionView::Helpers::FormBuilder
include ApplicationHelper
include FormHelper
include ActionView::Helpers::TagHelper
include ActionView::Helpers::FormTagHelper
def length_field(label,*args)
scale = 'medium'
args.each do |v|
if v.has_key?(:scale)
scale = v[:scale]
v.delete(:scale)
end
end
value = length_conversion(#object.send(label.to_sym),scale)
options = (args.length > 0) ? args.pop : {}
return has_error(label, text_field_tag(field_name(label),value,*args) + ' ' + length_unit(scale))
end
private
def field_name(label)
return #object_name + "[#{label}]"
end
def has_error(label, output)
return "<div class='fieldWithErrors'>#{output}</div>" if #object.errors[label]
return output
end
And it is used like this:
<%= form_for( #section, {:action => 'save', :id => #section.id}, :builder => SuperFormBuilder) do |sf| %>
<%= sf.length_field :feed_size_min_w, :size => 3, :scale => 'small' %>
<% end %>
The end result is a value in the appropriate unit based off their choice on system (Metric, Imperial) and scale IE small = inches or millimeters.
I basically copied the text_field method from the existing form builder, which uses the text_field_tag itself.
There are two gotchas: 1) Knowing the name of the object field and how to access the object to get the value which you want to format. 2) Getting the name right so when the form is submitted it is part of the correct params hash.
The form builder is given a class variable #object. You can get the value of the field using the .send method. In my case I send the label :feed_size_min_w to the #object and get its length back. I then convert it to my desired format, and give it to the text_field_tag.
The name of the field is key to having it end up in the params hash, in my instance the params[:sections] one. I made a little helper function called field_name that takes care of this.
Finally the has_error wraps the field in an error div if there are errors on that label.
I needed "nicer" format on some specified text fields, resolved it by adding this to my initializers. Seems to work nicely on Rails ~= 5.2 and it should be easy to customize.
class ActionView::Helpers::Tags::TextField
private
def value_before_type_cast # override method in ActionView::Helpers::Tags::Base
v = super
# format as you like, when you like
if #options.delete(:nice_decimal)
v = v.to_s.gsub('.', ',') if v.is_a?(BigDecimal)
end
v
end
end
Usage in form f
<%= f.text_field :foo, nice_decimal: true %>

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