Every time, when I'm getting the data from the API request, I require to compare and update records, if any changes was there.
for example i have saved User
user = User.first
user.name => 'name_one'
when i calling to api,api returns me User but name was cahnged to 'name_two'
so i need compare existing user with newly arrived and if name changed replace it
example of calling api
url= 'my api str'
result = Curl.get(url)
JSON.parse(result.body_str).each do |key, value|
value["commissions"].each do |k, v|
User.create(name: v["name"],etc... )
end
end
I will be glad for any suggestions.
You can also try the following:
u = User.first
u.name = "name_two"
u.name_changed? #=> true/false
u.name_was #=> "name_one" if it was "name_one"
These are called dirty method and very helpful for this kind of task.
Thanks
Try this code
u = User.first
u.name = "name_two"
u.save if u.changes.include?("name")
I believe you shall use active record's private method #read_attribute to compare current updated values with stores ones:
if send(:read_attribute, :attr) == self.attr
# value isn't changed
end
Additional info you can read here:
Validation from controller
You shall validate newly created record from controller:
v['name'] = 'User 1'
user = User.create(name: v['name'])
user.name # => # User 1
Related
I have a Rails site that logs simple actions such as when people upvote and downvote information. For every new action, an EventLog is created.
What if the user changes his or her mind? I have an after_create callback that looks for complementary actions and deletes both if it finds a recent pair. For clarity, I mean that if a person upvotes something and soon cancels, both event_logs are deleted. What follows is my callback.
# Find duplicate events by searching nearly all the fields in the EventLog table
#duplicates = EventLog.where("user_id = ? AND event = ? AND project_id = ? AND ..., ).order("created_at DESC")
if #duplicates.size > 1
#duplicates.limit(2).destroy_all
end
The above code doesn't quite work because if any of the fields happen to be nil, the query returns [].
How can I write this code so it can handle null values, and/or is there a better way of doing this altogether?
If I understood this correctly,
some of the fields can be nil, and you want to find activity logs that have same user_id, same project_id or project id can be nil.
So I guess this query should work for you.
ActivityLog.where(user_id: <some_id> AND activity: <complementary_id> AND :project_id.in => [<some_project_id>, nil] ....)
This way you would get the complementary event logs where user_id is same and project id may or may not be present
class ActivityLog
QUERY_HASH = Proc.new{ {user_id: self.user_id,
activity: complementary_id(self.id),
and so on....
} }
How about:
# event_log.rb
def duplicate_attr_map
{
:user_id,
:project_id
}
end
def duplicates
attribs = duplicate_attr_map.reject_if(&:blank?)
query = attribs.map { |attr| "#{attr} = ?" }.join(' AND ')
values = attribs.map { |attr| self.send(attr) }
EventLog.where(query, *values).order("created_at DESC")
end
def delete_duplicates(n)
duplicates.limit(n).delete_all if duplicates.size > 1
end
# usage:
# EventLog.find(1).delete_duplicates(2)
not tested, could be improved
I have a record and I want to inset it inside and array and later access it.
users = User.all
results = []
users.each do |user|
results << {:name => user.name, :email => user.email}
end
is results variable still an array ? If yes how can I get all the names alongwith email?
Your example would create an array results filled with hashes containing each users name and email.
You could access it in several ways, the easiest of which is a simple loop:
results.each do |result|
name = result[:name]
email = result[:email]
end
You can also access individual items directly like so:
first_result_name = results[0][:name]
but be careful of trying to access results that may not be there.
Arrays
Hashes
But I have to ask, why do you want to do this? There's no gain from assigning all the Users name and emails to an array, User.all is no different really in functionality.
Yes, it's still an array. You can have what you want later for example with:
results.each do |result|
result[:name] # access to name
result[:email] # access to email
end
You just need one line to do it
results = users.collect{|user| {:name => user.name, :email => user.email}}
In a kind of unrelated way, your initial code could be rewritten as:
results = User.all.inject([]) do |array, user|
array << {:name => user.name, :email => user.email}
end
Given that "results" now contains this collection of hashes, if you want to print every user name and email you would do:
results.each do |user|
puts "#{user[:name]} #{user[:email]}"
end
I would like to create rake task to set the username of all users' without a username to the part before the '#' in their email address. So if my email is test#email.eu, my username should become test. If it's not available, prepend it by a number (1).
So i have problem witch checking uniqness of username. Code below isn`t working after second loop ex: when i have three emails: test#smt.com, test#smt.pl, test#oo.com username for test#oo.com will be empty.
I have of course uniqness validation for username in User model.
desc "Set username of all users wihout a username"
task set_username_of_all_users: :environment do
users_without_username = User.where(:username => ["", nil])
users_without_username.each do |user|
username = user.email.split('#').first
users = User.where(:username => username)
if users.blank?
user.username = username
user.save
else
users.each_with_index do |u, index|
pre = (index + 1).to_s
u.username = username.insert(0, pre)
u.save
end
end
end
end
Other ideas are in Gist: https://gist.github.com/3067635#comments
You could use a simple while loop for checking the username:
users_without_username = User.where{ :username => nil }
users_without_username.each do |user|
email_part = user.email.split('#').first
user.username = email_part
prefix = 1
while user.invalid?
# add and increment prefix until a valid name is found
user.username = prefix.to_s + email_part
prefix += 1
end
user.save
end
However, it might be a better approach to ask the user to enter a username upon next login.
if i understand your code correct, you are changing the username of existing users in the else branch? that does not look as if it's a good idea.
you should also use a real finder to select your users that don't have a username. otherwise you will load all the users before selecting on them.
i don't know if it "matches your requirements" but you could just put a random number to the username so that you do not have the problem of duplicates.
another thing that you can use is rubys retry mechanism. just let active-record raise an error and retry with a changed username.
begin
do_something # exception raised
rescue
# handles error
retry # restart from beginning
end
In your query User.find_by_username(username), you only expect 1 record to be provided. So you don't need any each. You should add your index in another way.
I have an algorithm that searches through all of my sites users, finding those which share a common property with the user using the algorithm (by going to a certain page). It can find multiple users, each can have multiple shared properties. The algorithm works fine, in terms of finding the matches, but I'm having trouble working out how to store the data so that later I'll be able to use each unit of information. I need to be able to access both the found users, and each of the respective shared properties, so I can't just build a string. This is an example of the output, being run from the perspective of user 1:
user 4
sharedproperty3
sharedproperty6
user 6
sharedproperty6
sharedproperty10
shareproperty11
What do I need to do to be able to store this data, and have access to any bit of it for further manipulation? I was thinking of a hash of a hash, but I can't really wrap my head around it. I'm pretty new to programming, and Ruby in particular. Thanks for reading!
EDIT - Here's the code. I'm fully expecting this to be the most incorrect way to do this, but it's my first try so be gentle :)
So if I'm understanding you guys correctly, instead of adding the interests to a string, I should be creating an array or a hash, adding each interest as I find it, then storing each of these in an array or hash? Thanks so much for the help.
def getMatchedUsers
matched_user_html = nil
combined_properties = nil
online_user_list = User.logged_in.all
shared_interest = false
online_user_list.each do |n| # for every online user
combined_properties = nil
if n.email != current_user.email # that is not the current user
current_user.properties.each do |o| # go through all of the current users properties
n.properties.each do |p| # go through the online users properties
if p.interestname.eql?(o.interestname) # if the online users property matches the current user
shared_interest = true
if combined_properties == nil
combined_properties = o.interestname
else
combined_properties = combined_properties + ", " + o.interestname
end
end
end
if shared_interest == true
matched_user_html = n.actualname + ": " + combined_properties
end
end
end
end
return matched_user_html
render :nothing => true
end
This returns an array of hashes with all users and their corresponding sharedproperties.
class User
def find_matching_users
returning Array.new do |matching_users|
self.logged_in.each do |other_user|
next if current_user == other_user # jump if current_user
# see http://ruby-doc.org/core/classes/Array.html#M002212 for more details on the & opreator
unless (common_properties = current_user.properties & other_user.properties).empty?
matching_users << { :user => other_user, :common_properties => common_properties }
end
end
end
end
end
In your view you can do something like this:
<%- current_user.find_matching_users.each do |matching_user| -%>
<%-# you can acccess the user with matching_user[:user] -%>
<%-# you can acccess the common properties with matching_user[:common_properties] -%>
<%- end -%>
You can use a hash table with the key being the user object and the value being an array of the shared properties . This is assuming that you first need to do a lookup based on the user .
Something like this :
#user_results = { user1 => [sharedproperty3,sharedproperty7] , user2 => [sharedproperty10,sharedproperty11,sharedproperty12]}
You can then acces the values like :
#user_results[user1]
or you can also iterate over all the keys using #user_results.keys
Currently, in my request model I have:
belongs_to :requestor, :class_name => 'User'
So the requestor is the current_user.
Problem is when the current_user clicks the create button to submit a form for a request, all of the attributes get updated to the database that are in the form.
But since requestor_id is not a value to fill out in the form, that brings back a value of null in the database when the new request record is created.
What I want is an integer (which equates to the primary key of the Users table) updated in the requestor_id column in the request table when the user clicks the create button.
So I thought that maybe adding a requestor_id as a symbol in the params for the create action would solve that:
def create_common
#a = Request.new
b = #a.requestor_id
#resource = yield params[:contact + "#{b}".to_sym]
self.resource = #resource
But instead it returns the following error:
interning empty string
Thanks for any suggestions.
I kept getting this error. I traced it to very simple code and reproduced in the console with this:
ruby-1.8.7-p174 :084 > a = 'fred'
=> "fred"
ruby-1.8.7-p174 :085 > a.to_sym
=> :fred
ruby-1.8.7-p174 :086 > a = ''
=> ""
ruby-1.8.7-p174 :087 > a.to_sym
ArgumentError: interning empty string
from (irb):87:in `to_sym'
from (irb):87
Can you not just pass the Request the current_user when you create it?
#req = Request.new(:requestor => current_user)
I am not quite sure what the yield params statement is meant to be doing,
If I'm understanding your question correctly, you want to assign the current_user's id as the requestor id to the Request model?
# assign values passed in via form
#request = Request.new(params[:request])
# assign current_user to request
#request.requestor = current_user
# save the request
#request.save!
Hope this helps!
I had a '.' in an error message similar to:
errors.add('You entered a non-supported widget.')
and was getting the "interning empty string error"
This post saved me:
http://www.tonyamoyal.com/2009/10/20/interning-empty-string-error-in-ruby-on-rails/
Simply changing to:
errors.add('You entered a non-supported widget')
fixed it. Rails 2.3.4 and Ruby 1.8.5