I am building a medication reminder system using Ruby on Rails to be deployed on heroku.
Using this system a doctor will enter a patient's medication details including medication name, dose as well as timing details and the app will then notify the patient via sms when its time to take his/her medicine.
I have developed the application but I am stuck on the sms part since that involves running a process over and over again until the medication's period has elapsed.
I want to be able to run a script from a rails app that will repeatedly query the database and when it is time to send a sms it will dispatch it to the patient. This cannot function in the normal request/response web cycle.
I explored rubygems that allow developers to create background jobs such as rufus scheduler and resque but I can't seem to figure out how to go about doing this.
Please help I am open to all types of suggestions. I am using Twilio for sending sms
I don't know about resque/rufus, but I know that sidekiq has the ability to queue jobs, but have them delayed till a certain time.
https://github.com/mperham/sidekiq/wiki/Delayed-Extensions#advanced-options
You'd need to look into how exact the delay is (ie. what sidekiq's polling frequency is) depending on your needs, but I would suspect this would work well.
It would require another dynamo or whatever heroku calls it these days.
I use delayed_job using the run_at param to send scheduled SMS via Twilio from Heroku.
I have a send_message method on my message model that does the actual send with the Twilio API. I chose to create a custom job with Delayed Job so when I schedule the message:
Delayed::Job.enqueue my_custom_job, :run_at => TIME_I_WANT_TO_SEND
Using a the heroku worker to run the background task of sending has been very reliable.
Since you're deploying to Heroku, reading their documentation about scheduling jobs is a must for you:
https://devcenter.heroku.com/articles/scheduler
Related
I've used this instructions and sent "Welcome" mail to my signed up user. But this makes the user wait for 5-8 seconds because the server is trying to complete this mail thing.
I don't want the user to wait until the mail is sent but immediately see the "Mail has sent" message. So this brings me background jobs in Rails.
There are many options like delayed_job, Resque etc for background jobs in Rails. But to use these kind of solutions, as I understand:
1- Create a background job
2- Run this job
Let's say I used one of the background job solutions, so then I need something else to run also this job, like cron job...
I think just for sending sign-up and password reminder emails, another easier solution should be possible. I mean like another external service that 1- I'll create a template for each kind of mail I'll send, 2- I'll pass some arguments like receiver_email, template_id, receiver_username, password_link etc... With that way, I won't need any background job, and the user will not wait.
I came across some other gem called "sucher_punch" but as I understand from the people's messages and posted problems, with using heroku, this gem can fail for some reasons of heroku dynos and the mail may not be sent, and you don't know it.
Anyway, what is the general way that rails developers handle this email issue? Maybe I can also use sendgrid like the way I explained above, can I ?
Sending emails in the background is such a common use case, Rails 4.2 introduced a #deliver_later method in ActionMailer to provide seamless ActiveJob integration.
You don't need to set up a cron job to check if there are any jobs in the background queue. Sidekiq, Resque or DelayedJob will take care of that for you.
It seems Sendgrid does allow creating templates and sending variable content to fill them up, but that feature doesn't undermine the benefits of making that call asynchronously. In fact, deferring it to the background also has the added benefit of not disrupting user experience if the external resource(Sendgrid) is unavailable.
You should try installing one of the background processing solutions you mentioned(I recommend sidekiq) and take advantage of the ActionMailer + ActiveJob integration.
I am attempting to build a web application with Ruby on Rails that users site up for and get an email alert when a certain event happens.
As such, I need to be able to make an API call and then based on the JSON response, send the alert, but I need a way to have this API call happen repeatedly for an indefinite amount of time automatically. I am also using Heroku at this time if that needs to be taken into account.
Thanks for your help.
This sound like a cron job in plain old linux. Heroku calls this addon Scheduler. You have to define the task withing lib/tasks/scheduler.rake
For further information read the heroku docs for scheduler here
I have this scenario: A user buys a product and when two days have passed after the transaction has been processed, I need to send a mail notification to buyer.
At this moment my idea is to use whenever gem and check build a cron job to check in each day and if 2 days have passed and if true, cron job will send mail notification.
I don't know if is ok to do this... Can you give me better solution?
You can use ActiveJob with perform_later, like:
NotificationSendJob.set(wait: 2.days).perform_later(record)
Note that not all backends support this. You can see check feature matrix here: http://api.rubyonrails.org/classes/ActiveJob/QueueAdapters.html
Rather that using whenever,I would suggest using sidekiq which is a background processing library. The cron job has to be executed everyday(in your particular case). It doesn't consider whether a mail has to be sent or not. The job will still be executed even if no mails are to be sent, which is a wrong approach.
You can use a background processing library like sidekiq to schedule the job in the background. checkout https://github.com/mperham/sidekiq/wiki/Scheduled-Jobs
I have some questions about ActionMailer :
How does Actionmailer connect to a smtp server ?
Are the connections concurrent or parallel if the number of emails high > 1000 ?
How will sending out emails like facebook does ( 1000's in numbers ) as immediate emails affect the ruby on rails application and how would actionmailer handle it ?
Any other solution/plugin to send out large number emails from a RoR application apart ActionMailer?
------------------------------------------------added :
We need to send out at least 1000 emails per 15 minutes . We are using a Notes Domino server as our smtp server .! what is the possible architecture for this kind of problem. We are already storing the emails in the database to send them later , but what is needed is the sending approach !
The usual thing is to create a background job to send email. ActionMailer is very good for single emails but does tend to run into trouble after sending multiple emails as each one can take several seconds to complete. That's why I created PostageApp to help solve those problems.
Some services on the market to help you with sending lots of email from Rails:
MailGun
SendGrid
PostmarkApp
MailChimp
Mailjet
PostageApp
All of these have ways of sending multiple messages with a single API call or SMTP transaction.
1) Actionmailer connects to your smtp server via a set of parameters including a host, port and protocol.
3) The effect will be a slow site as a result of the many synchronous tasks being executed.
2 & 4)
Actionmailer is a bit too slow to be sending out a ton of emails under load, remember that it is a synchronous operation and as such its not really the sort of thing you want to be doing a lot on a busy site.
To be honest you're better off not sending that quantity of email from your website. It's not really designed to be used in such a way. If I had to send that sort of volume I'd look at doing the work in the background, something like Delayed Job would work well here or one of the many async rails mailers found here would do the trick.
What you really want to look at here is the requirement that you're trying to fulfil, is it absolutely necessary that the website be responsible for sending the mail in a synchronous fashion? In most cases the answer to that question is no. If you can, you'll be far better off deferring this sort of task to another part of your system, keep your site as lean and focused as you can.
Simple solution here for you...
Sidekiq or Resque
I'd highly recommend Sidekiq as it's not near as server intense for running multiple workers for this one - only be careful with concurrency issues (make sure you don't have 2 workers pick up the same job and send duplicate emails that is).
Say you set 20 Sidekiq workers, each should be able to send an email every 2-4 seconds, you're looking at an easy 300-600 per minute.
DO NOT try to do this without background workers like Sidekiq, Resque, or DelayedJob. You will freeze your entire app if you try sending in app with any large amount of emails. Even sending activation emails in app and what not will cause you unnecessary slow down issues.
I'd have one Worker that handles the queueing periodically and another Worker class that handles the sending. We're using Resque (6 workers maybe?) for this on an older app (pre-sidekiq) to send around 500 emails every 5 minutes with no issues.
You can aways use a third party like someone mentioned. Sendgrid is decent. But that wasn't the question, this is how you do it yourself simply and easily.
You define the SMTP settings in a config file if left blank it uses sendMail local
concurrent
multiple handlers
Is there a bulk email plugin for Rails apps?
you may also do 1000.times do email.deliver but it will probably collapse ur server
For my side project kwiqi, I use ActionMailer's 'receive' method to process incoming email messages for tracking my expenses. Heroku doesn't have a local mail server running that same code will not work. One solution I've thought of is to periodically hit a controller action that will pull messages from Gmail. Are there other solutions that are reasonable? Is anyone processing incoming emails in Heroku?
You can use sendgrid addon, and their parse api (http://wiki.sendgrid.com/doku.php?id=parse_api). I've written a short tutorial on how to do so here: http://nanceskitchen.com/2010/02/21/accept-incoming-emails-into-a-heroku-app-using-sendgrid/
I know that this is a little late but for anyone else that might find this useful in future we created the http:///CloudMailin.com addon for Heroku that should help you to receive email on Heroku Rails apps really easily.
Heroku support running workers using DelayedJob. Workers are resourced just like Dynos (you pay by the hour) and for this you get a dedicated resource to process your emails.
In the past I have used Cron calling a controller in my app. It's pretty effective.
If the hourly limitation is an issue, you can call your app from another location ... I have a cheap Dreamhost account for some of my non-priority sites that I have used as Cron systems.
There are also a number of ping and uptime services that you can use for this purpose as well ... simply pass these services your email controller.
A real limitation of Heroku currently is that the most rapid frequency they support for cron jobs is hourly.
I'd recommend using Gmail and using delayed job as an alternative to cron to set a more reasonable frequency. There is a good tutorial on setting this up at WiseJive