I want to schedule daily reports to subscribed users via email.
For that I have written action in reports_controller that fetch data from database & convert it into pdf using pdfkit/wkhtmltopdf.The action works fine when called from get request.But when converted so that be defined like
def self.dailymail
ac = ActionController::Base.new()
kit = PDFKit.new #retrieve data from db
pdf = kit.to_pdf
ReportMailer.send_reports(ac.send_data(pdf)).deliver
end
It raises exception at send_data call when used with rufus scheduler:
RackDelegation#content_type= delegated to #_response.content_type=, but #_response is nil: #<ActionController::Base:0x206b068 #_routes=nil, #_action_has_layout=true, #_headers={"Content-Type"=>"text/html"}, ...
so, my question is what how can I solve this problem or Is there any alternate scheduler in rails that work fair on both Windows and Linux?
I wish to know any scheduler that can be helpful to send reports fetched from database.
I agree with claasz regarding the rake task. Check out the whenever gem https://github.com/javan/whenever
There is no suport for windows Task Scheduler, but it does support creating cron jobs.
Check out the documentation for the details, but esentially the gem creates cron jobs based on what you configure in the schedule.rb file that is created when you install the gem.
sample content of schedule.rb:
every 3.hours do
runner "MyModel.some_process"
rake "my:rake:task"
command "/usr/bin/my_great_command"
end
This would be like running bundle exec rake my:rake:task every 3 hours
After creating the schedule.rb you will need to run the whenever command from the console in order to add your schedule to cron. If you run whenever without arguments, the output shows you the contents of the schedule.rb. There is an argument you need to provide that I can't remember off the top of my head, just pass --help and I think you'll get the answer.
Hope this helps
EDIT:The argument is -w to write to cron-tab
As willglynn already points out, you should get rid of any controller interaction. There's simply no need here and it makes things unnecessarily complicated. So your code should look more like
def self.dailymail
kit = PDFKit.new #retrieve data from db
pdf = kit.to_pdf
ReportMailer.send_reports(pdf).deliver
end
If you got problems with the rufus scheduler (which I don't know), you could create a rake task to send out your mails and use the OS scheduler (e.g. cron on Linux) to call the task. Having the rake task would be also convenient for testing.
Related
I am creating an automatic raffling system. I have a draw button that will run a draw function to select a winner or winners and it sends an email to the admin.
I want this to be a completely automated system so that the admin only has to create the raffles and they receive an email with who won after the draw date has passed. My raffles have a draw date associated with them and once that passes, I need the function to be called.
How do I tell the application to check the time/date to see if any of the raffle draw times have passed? I have looked everywhere and cannot seem to find a way to do it.
You could use the whenever gem to define a job that runs hourly (or however often you want), checks the draw dates, and runs the draw for any that have passed.
I use Clockwork in my rails apps whenever I need to schedule things. Simply set it up to run a job when you want and do your logic within that job to see which raffles need to be processed. Example:
Clockwork config
every(1.day, 'Raffle::CheckJob', at: '01:00')
Job
Raffle.not_complete.find_each(batch_size: 10) do |raffle|
if raffle.has_ended?
// logic
end
end
You should write a rake task and add it's execution to your crontab on server. You can use whenever gem to simplify crontab scripting and auto update on each deploy (whenever-capistrano/whenever-mina). Example of your rake task:
namespace :raffle do
task :check do
Raffle.get_winners.each do |w|
Mailer.send_win_mail(w).deliver_later
end
end
end
deliver_later is background execution in queue by the queue driver you use (DelayedJob/Rescue/Backburner etc)
I'm trying to understand how to use whenever properly, or if I'm even using it for the right thing. I've created a job:
class ScheduleSendNotificationsJob < ActiveJob::Base
queue_as :notification_emails
def perform(*args)
user_ids = User.
joins(:receipts).
where(receipts: {is_read: false}).
select('DISTINCT users.id').
map(&:id)
user_ids.each do |user_id|
SendNotificationsJob.create(id: user_id)
Rails.logger.info "Scheduled a job to send notifications to user #{user_id}"
end
end
end
I'd like to perform this job ever day at a set time. The job polls to see if there are any outstanding notifications, batches them, and then sends them to users so that a user can get one email with a bunch of notifications instead of a bunch of emails with one notification per email. I tried doing this with Delayed Job, but it seems it's not designed to schedule something on a recurring basis. So now I'm trying to do it with the whenever gem, but I can't seem to figure out how to set it up properly.
This is what I have in my config/schedule.rb file:
every 1.minute do
runner ScheduleSendNotifications.create
end
When I run whenever -i in the console I get the following:
Lorenzs-MacBook-Pro:Heartbeat-pods lorenzsell$ whenever -i
config/schedule.rb:13:in `block in initialize': uninitialized constant Whenever::JobList::ScheduleSendNotifications (NameError)
What am I doing wrong here? Should I be using something else? I'm just learning ruby and rails so any help is very much appreciated. Thank you.
The whenever gem takes a string as the argument to the runner function. Whenever doesn't actually load the Rails environment so it doesn't know about your ScheduleSendNotifications class.
The code below should get the crontab set up correctly to run your job.
every 1.minute do
runner "ScheduleSendNotifications.create"
end
From your project directory run whenever -w to set up the crontab file. Run crontab -l to view the written crontab file. Every minute the system will execute your Rails runner. From there you may need to debug your ScheduleSendNotifications.create code if something isn't working.
Is it possible to invoke ActionMailer from a cron job? We're using Rails 3.
Ideally, a cron job triggers a script to read users from a database, passes these users and some variables to an ActionMailer class to fire off emails.
Is this possible in Rails 3.2.12?
Yes it is possible. You could use a task to invoke with the rake command. Your task could be something like this:
# lib/tasks/cron.rake
namespace :cron do
desc "Send account emails"
task deliver_emails: :environment do
accounts_for_delivery = Account.where(condition: true)
# ... whatever logic you need
accounts_for_delivery.each do |account|
Postman.personalized_email_for(account).deliver
end
end
end
And your mailer and the corresponding view could look like this:
# app/mailers/postman.rb
class Postman < ActionMailer::Base
def personalized_email_for(account)
#account = account
mail to: account.email
end
end
# app/views/postman/personalized_email_for.text.haml
= #account.inspect
Now you can set the crontab to run your rake task just like you perform rake tasks. I recommend you use the whenever gem, that really provides a nice way to define cronjobs for your application that looks like this:
# config/schedule.rb
every 6.hours do
rake 'cron:deliver_email'
end
So now the cronjob definitions are bound your application. It works well with Capistrano between deployments as well. You can also pass variables at your task or execute system commands.
If everything else fails you can just create a normal controller action and let the cronjob call it with curl.
Otherwise any script in your Rails apps script folder can be started with rails runner script/myscript.rb from the commandline and has full access to all Rails features.
You can use rails r (rails runner) to run a script in your rails app. It runs it, loading in the full context of your rails app before doing so, so all your models etc. are available. I use it a lot. For example,
rails r utilities/some_data_massaging_script.rb
From cron, you'd obviously need to give it the full path to your app.
The old-fashioned way was to have something like:
require "#{File.dirname(__FILE__)}/../config/environment.rb"
at the top of your script (adjusting the relative bit of the path depending on the subdirectory level of your script in your app of course) and then just run your script using ruby, but rails r makes that unnecessary.
When a new resource is created and it needs to do some lengthy processing before the resource is ready, how do I send that processing away into the background where it won't hold up the current request or other traffic to my web-app?
in my model:
class User < ActiveRecord::Base
after_save :background_check
protected
def background_check
# check through a list of 10000000000001 mil different
# databases that takes approx one hour :)
if( check_for_record_in_www( self.username ) )
# code that is run after the 1 hour process is finished.
user.update_attribute( :has_record )
end
end
end
You should definitely check out the following Railscasts:
http://railscasts.com/episodes/127-rake-in-background
http://railscasts.com/episodes/128-starling-and-workling
http://railscasts.com/episodes/129-custom-daemon
http://railscasts.com/episodes/366-sidekiq
They explain how to run background processes in Rails in every possible way (with or without a queue ...)
I've just been experimenting with the 'delayed_job' gem because it works with the Heroku hosting platform and it was ridiculously easy to setup!!
Add gem to Gemfile, bundle install, rails g delayed_job, rake db:migrate
Then start a queue handler with;
RAILS_ENV=production script/delayed_job start
Where you have a method call which is your lengthy process i.e
company.send_mail_to_all_users
you change it to;
company.delay.send_mail_to_all_users
Check the full docs on github: https://github.com/collectiveidea/delayed_job
Start a separate process, which is probably most easily done with system, prepending a 'nohup' and appending an '&' to the end of the command you pass it. (Make sure the command is just one string argument, not a list of arguments.)
There are several reasons you want to do it this way, rather than, say, trying to use threads:
Ruby's threads can be a bit tricky when it comes to doing I/O; you have to take care that some things you do don't cause the entire process to block.
If you run a program with a different name, it's easily identifiable in 'ps', so you don't accidently think it's a FastCGI back-end gone wild or something, and kill it.
Really, the process you start should be "deamonized," see the Daemonize class for help.
you ideally want to use an existing background job server, rather than writing your own. these will typically let you submit a job and give it a unique key; you can then use the key to periodically query the jobserver for the status of your job without blocking your webapp. here is a nice roundup of the various options out there.
I like to use backgroundrb, its nice it allows you to communicate to it during long processes. So you can have status updates in your rails app
I think spawn is a great way to fork your process, do some processing in background, and show user just some confirmation that this processing was started.
What about:
def background_check
exec("script/runner check_for_record_in_www.rb #{self.username}") if fork == nil
end
The program "check_for_record_in_www.rb" will then run in another process and will have access to ActiveRecord, being able to access the database.
I have a Rails app with some basic models. The website displays data retrieved from other sources. So I need to write a Ruby script that creates new instances in my database. I know I can do that with the test hooks, but I'm not sure that makes sense here.
I'm not sure what this task should look like, how I can invoke it, or where it should go in my source tree (lib\tasks?).
For example, here's my first try:
require 'active_record'
require '../app/models/mymodel.rb'
test = MyModel.new
test.name = 'test'
test.save
This fails because it can't get a connection to the database. This makes sense in a vague way to my newbie brain, since presumably Rails is doing all the magic work behind the scenes to set all that stuff up. So how do I set up my little script?
You can load the entire rails environment in any ruby script by simply requiring environment.rb:
require "#{ENV['RAILS_ROOT']}/config/environment"
This assumes the RAILS_ROOT environment variable is set, see my comment for other ways of doing this.
This has the added bonus of giving you all the nice classes and objects that you have in the rest of your rails code.
To kick off your processes it sounds like cron will do what you want, and I would also add a task to your capistrano recipe that would add your script to the crontab to periodically get the data from the external source and update your DB. This can easily be done with the cronedit gem.
The cron approach does have some drawbacks, mostly overhead and control, for other more sophisticated options see HowToRunBackgroundJobsInRails from the rails wiki.
I agree with the answer above but you have to include => :environment in your task or it will not load the Rails environment.
e.g.,
namespace :send do
namespace :trial do
namespace :expiry do
desc "Sends out emails to people who's accounts are about to expire"
task :warnings => :environment do
User.trial_about_to_expire.has_not_been_notified_of_trial_expiry.each do |user|
UserMailer.deliver_trial_expiring_warning(user)
user.notified_of_trial_expiry = true
user.save
end
end
end
end
end
I'd suggest creating custom rake tasks (lib/task/foo.rake). This give you easy access to most of the functionality of your rails app.
namespace :foo do
desc 'do something cool'
def something_cool
test = MyModel.new
test.name = 'test'
test.save
end
end
Then:
$ rake -T foo
rake foo:something_cool # do something cool
You can even run the tasks via a cronjob.
I wrote up a post about this a while back.
http://www.rawblock.com/2007/06/14/ruby-oracle-mac-os-x-pain-jruby-and-activerecord-jdbc-to-the-rescue/
You can open a connection in your scripts as such:
ActiveRecord::Base.establish_connection(
:adapter => "mysql",
:username => "root",
:host => "localhost",
:password => "******",
:database => "******"
)
I'm sure there is a more elegant way to do it, so that it grabs the info from your database.yml.
There are few steps to this and more details needed to really answer well.
You say your site retrieves data from other sources? How often? If it is semi-regularly you definitely want to look into background processing/messaging. If it is frequently you really want to avoid loading your rails environment every time your script runs since you will be paying too high a startup tax each time.
There are a multitude of options out there you will want to research. Reading about each of them, particularly reviews from people who post about why they made the choice they did, will give you a good feel for what questions you need to ask yourself before you make your choice. How big a job is loading the data? etc...
Off the top of my head these are some of the things you may want to look into
Script/Runner & Cron
Background/RB
Starling
Workling
MemcacheQ
Beanstalk
Background Job (Bj)
delayed_job (Dj)
Daemon Generator
Check out my answer in "A cron job for rails: best practices?".
It contains two examples for using cron to run Rake tasks and class methods (via script/runner). In both cases, Rails is loaded and you can use your models.
Nice Joyent write up of using rake to run rails tasks from a cron job - http://wiki.joyent.com/accelerators:kb:rails:cron
Easiest way to run ruby tasks that interact with rails app/models is to make Rails generate Rake tasks for you!! :)
Here's an example
run rails g task my_namespace my_task
This will generate a file called lib/tasks/my_namespace.rake which looks like:
namespace :my_namespace do
desc "TODO: Describe your task here"
task :my_task1 => :environment do
#write any ruby code here and also work with your models
puts User.find(1).name
end
end
Run this task with rake my_namespace:my_task
Watch your ruby code task that interacts with rails modal run!