I'm trying to store some additional data along with the standard error message in a custom validator in Rails 3.
For example, (ignoring built-in validators) suppose I wanted to check to see if a post is a duplicate before it's saved. I might write my custom validation method like this:
class Post < ActiveRecord::Base
# prevent duplicate posts
validate do |post|
duplicates = Post.find_all_by_body(body)
errors.add_to_base("Post is a duplicate!") if duplicates.length
# something like this is desired:
# errors.add_to_base("Post is a duplicate",
# :extra => { :duplicates => duplicates })
end
end
This will let the user know there are duplicates, but along with adding the error message I would also like to store the duplicates so they can be displayed to the user. How would I store the list of duplicate posts retrieved during validation such that it is associated with the record's errors for the body field, and available to my view?
A simpler example might be length validation: If a field exceeds its maximum length, how can I store the maximum length along with an error message without simply interpolating it into the message as Rails currently does?
I have not had to do this before, but my first thought is to create a new method on the object called duplicates.
attr_accessor :duplicates
Then in your custom validate method, you can set the duplicates on the object making them available to the view when you render the errors. Notice your current code doesn't change much:
validate do |post|
duplicates = Post.find_all_by_body(body)
errors.add_to_base("Post is a duplicate!") if duplicates.size > 0
end
You would then have to intercept that error in the view manually so that you can print out all the duplicates if the "Post is a duplicate!" error is encountered.
You can pass options to the error but they are only used as substitution in i18n templates. To make a long story short, no you can't store meta-data about your error in the errors hash. If you need such a functionality you'll need to look into the ActiveModel::Errors module in Rails core.
Update:
Another solution could be that instead of pushing a string into error hash, you stuff an instance of your own class, a class which quacks like a string but would be decorated with extra methods and state and such like.
Related
I'm trying to display some error messages from my model in Rails. Currently, when an exception is caught in my test model and raised, the messages are returned as expected in the errors scope of my object. The messages are returned as follows:
{:key1=>["Your key needs to be different."],
:key2=>["Another exception"]}
This is perfect, as the correct exceptions are being thrown for the correct errors. What I'm trying to do now is bind these messages to the flash scope so that I can display them on my view. In my controller, when I have an exception, I then bind it to the flash[:error] scope as follows:
flash[:error] = #test.errors.messages
render :new
Upon doing this, my errors are bound to the flash scope, but when I output them on my view, they are displayed as follows:
[:error, {:key1=>["Your key needs to be different."], :key2=>["Another exception"]}]
All I'd like to do is display each one of these messages so that they look to be like:
Your key needs to be different.
Another exception.
Notice that in the above example, all that will be rendered is the message text.
Will you please point me in the right direction as to what I need to change either in my controller or in my view to achieve the desired output above?
Thank you in advance.
The one place I immediately see for improvement is in the hash you're passing.
If there's not a specific reason you're wrapping your strings in an array, you can eliminate the array:
{
:key1 => "Somebody poisoned the watering hole!",
:key2 => "There's a snake in my boot."
}
That will both simplify your code and eliminate the two-dimensional array you didn't seem to be intending to create.
If there is a reason you're wrapping your strings in an array (multiple messages per key?), you'll need to revisit your iterator; the way it's written now, it's only going to display the first string for any given key.
I noticed that when I looped over #test.errors.messages in the following construct, I ended up with a 2-Dimensional array:
[:key1, ["Your key needs to be different."]]
[:key2, ["Another exception"]]
Since this is a multidimensional array, I was able to then simply loop over the array in my erb and get the value to display as requested in my question:
<% for i in flash[:error] %>
<%= i[1].first %><br />
<% end %>
Returns on the screen:
Your key needs to be different.
Another exception.
I'm always open to suggestions, so if there's a better way to handle this, then please advise! Otherwise, this does work for me.
I have an application that collect user input and store to DB and show back to user.
One user entered "alert(1)" into the name field and saved it into DB.
Whenever the name is displayed, the page will be broken.
I know how to fix that input only with validation for input, and h() for output.
However, I have so many input fields and so many outputs that accept users' text.
Is there any simple way to prevent this happening(i.e. overriding params method, etc)?
I also want to know how you expert guys are dealing with this problem?
As of Rails 3, my understanding was that embedded ruby code was html escaped by default. You don't need to use h() to make it that way. That is, if you use <%= "<script>a=1/0;</script>" %> in a view, the string is going to be made html safe, and so the script doesn't execute. You would have to specifically use raw() or something similar to avoid it - which you should naturally not do unless you're really confident about the contents.
For output, Rails 3 automatically html-encode all text unless I use raw() method.
For input, How about making a common validator and apply to all fields that are text or string? Is it desirable?
http://api.rubyonrails.org/classes/ActiveModel/Validator.html
class MyValidator < ActiveModel::Validator
def validate(record)
record.class.columns.each do |c|
if c.type==:text || c.type == :string
record.errors.add c.type, "script tag is not allowed" if c[/<script[^>]*>/]
end
end
end
end
Using the rally-api I have been trying to access the portfolio kanban state value of items eg.
features.each do |feature|
puts feature.State # also tried feature.State.Name
...
end
But this always return an empty string.
this looks to be a back end WSAPI change that is coming. PI states are going to become readable via the wsapi in 1.37, but they are not currently returned when you query for Portfolio Items. When wsapi 1.37 comes out, if you pass :version => 1.37 to the config to rally_api, you should then be able to get it in the fetch string.
It is easily accessed by using "feature.State.Name". However, in the Ruby toolkit, these fields are all lowercase, with Pascal-cased field names using underscores(_) to represent the casing. It should be, in this case:
put feature.state.name
and in a more complex case (PlannedRemovalDate):
put feature.planned_removal_date
Hope this helps.
Currently my URL's appear as www.website.com/entries/1, I'd like to make them appear as www.website.com/title-of-entry. I've been messing around with routes and have been able to get the entry title to display in the URL, but Rails is unable to find the entry without supplying an ID. If I send the ID along with the parameters, the URL appears as www.website.com/title-of-entry?=1. Is there anyway I can pass the ID without having it appear in the URL as a parameter? Thanks!
Like most things, there's a gem for this.
FriendlyID.
Installation is easy and you'll be up and running in minutes. Give it a whirl.
Ususally you'll want to to save this part in the database title-of-entry (call the field slug or something`). Your model could look something like this:
class Entry < ActiveRecord::Base
before_validation :set_slug
def set_slug
self.slug = self.title.parameterize
end
def to_param
self.slug
end
end
Now your generated routes look like this: /entries/title-of-entry
To find the corresponding entries you'll have to change your controller:
# instad of this
#entry = Entry.find(params[:id]
# use this
#entry = Entry.find_by_slug(params[:id])
Update
A few things to bear in mind:
You'll have to make sure that slug is unique, otherwise Entry.find_by_slug(params[:id]) will always return the first entry with this slug it encounters.
Entry.find_by_slug(params[:id]) will not raise a ActiveRecord::RecordNotFound exception, but instead just return nil. Consider using Entry.find_by_slug!(params[:id]).
If you really want your routes to look like this /title-of-entry, you'll probably run into problems later on. The router might get you unexpected results if a entry slug looks the same as another controller's name.
I'm doing something like the following: Validate number of nested attributes.
I'm checking for existence of at least one nested attribute.
This was working fine when I was using a text input for the date but I've changed it to use a date_select instead and now the same validation code shows an error saying that not enough have been chosen.
When it fails validation and reloads the form it also doesn't "build" an instance of the nested attribute either so it just shows my "[+]" link
Anybody got any ideas?
Failing everything I'll just have to put the text field back (probably using type=date).
Col
I decided to just put the text field back.