Rails appends a timestamp to js and css files to force cache refreshes while in development mode. While this is appropriate most of the time, it backfires when using CSSEdit, for example, that does not take the timestamp append into consideration.
If you attempt to create a new style or edit an existing selector it will attempt to reload the page each time, even though you've opened a file once. This is a conversation I had a long time ago with Jan, however I've never seen a mechanism added to address this situation.
Is anyone aware of either:
A) a hack to allow CSSEdit to cut off the ?##### timestamp or
B) just simply temporarily disable rails timestamps via the rails server command (or perhaps just throw an awk into it to change a config file via a script to start the rails dev server on localhost)?
RAILS_ASSET_ID='' rails s actually does the trick for anyone needing to work with CSSEdit and Rails to temporarily disable the modification postfixes when dealing with the cache-buster.
This is handy since it's a temporary solution and will go back to the normal operation when you go back to running rails without the RAILS_ASSET_ID command prepend.
Related
I am using Solidus for the first time. I have been able to have it working as required. However, I am trying to make changes to the frontend. Although I'd rather use bootstrap 4, I could only find a way to port it with bootstrap 3 using a gem as described here.
I have followed the instruction as explained on the page. However when I make the test changes described, expecting to see the same changes, nothing happens. In fact the page is no longer structured as it was initially which I suppose is due to overwriting all.css used by spree on the app.
I am not sure why things are not working. I tried to undo changes by running rails destroy solidus_bootstrap_frontend:install but this doesn't restore the changes. Any help would be appreciated.
Thanks.
run
rails solidus_bootstrap_frontend:install
It'll tell you what files it tries to create, and will probably ask if you want to overwrite them.
Delete these files and you'll reset the appearance to how it was before you ran the command
I'm completely new to Ruby on Rails, have never worked on it, but I am supposed to take over somebody else's old project. He designed a webapp that logs into a website/server online, extracts data from it daily and performs calculations. However, the application has not been running for quite some time, so now when it tries to display statistics, the page crashes. It uses data from a 5 week period and currently only has data for 2 days.
I need to manually insert data for the missing weeks in order to get it up and running again, but the problem is I don't know how to find/access its database, nor how exactly to use Ruby on Rails. I found several files in the db directory of his project, however they were mostly .sqlite33 files or just 'files'. I downloaded sqlite precompiled binary for Windows and tried to use it, but not sure what to do. I also downloaded and tried using SQTView to open the files to change the tables, but I have had no luck.
How can I tell which file is the main database and how do I edit it? And what are .sqlite33 files? Thanks.
EDIT
The application produces a
TypeError in HomeController#index
"nil can't be coerced into Float"
It links the error to a line in the code, but the only reason the error happens is because there is no data in the table for the time period that the variable in this line of code tries to use. That is why I want to manually update it with values.
I think that Sqliteman might do the trick and thank-you for explaining all of this to me. I just have to confirm it works after editing.
EDIT2
Okay, so I had a small revelation while experimenting on his app. It turned out that the page crashed because of empty values for full weeks. If I used the app to gather data for at least one day per week up until this week, then the app worked.
Is there a way I can populate all the missing days without having to manually click the days in its calendar because it takes a good 20-30 seconds for it to load?
Thank you very much for your help.
A Rails application's database is defined in config/database.yml - though the database itself and the scheme are in the db folder. In database.yml you'll find three database configurations - development, test and production - so make sure to choose the right file.
I've never heard of .sqlite33 files, but to edit SQLite files manually I recommend SQLiteMan. But I don't recommend editing it manually.
What I do recommend is to check if you are running the app in development or production mode, as the two mods use different databases. Try to run it in the other mode.
If that doesn't work, try saving a copy of the database files, and running the commands:
bundle install
bundle exec rake assets:precompile
rake db:migrate
rake db:migrate RAILS_ENV="production"
(if you're using Linux, you might want to also run the first command with sudo)
Those commands make sure all the required gems are installed, that the precompiled assets are up to date, and that the database fits the schema. If you are running that application on the same machine and with the same database as the ones the other guy was using, than those commands shouldn't be necessary, but if you have moved the application to your own machine, or used an used an outdated db file, than those commands might fix the crash.
At any rate, if you tell us what error the application is producing we might be able to provide more assistance.
I'm using the configatron gem for a new Rails app that is backed up by ActiveRecord. Some of my configatron settings are set in a file and some are pulled from DB, as they will change from time to time, here are a couple of lines from my configatron.rb
configatron.app.uptime.start = Time.now
configatron.email.signature = Setting.where(:keyname => "email_signature").first.value.to_s unless Setting.where(:keyname => "email_signature").first.nil?
Since this app sends multiple emails from multiple mailers - that is a good way to keep this global config in one place, plus it reduces db lookups for signature. If for some reason site admin decides to change it - they can do it through web admin interface that will update my settings table ( tied to Setting model).
This is all jolly & good, however what is the best place to store configatron.rb? Right now it's sitting in my initializers folder. Which means it will load once on application startup - which is good, however if one of the settings changes - site admin decides to tweak email signature to mention a new promotional website - in order for the change to take effect - I would need to restart app ( running passenger - so it trivial to do touch tmp/restart.txt from code). However that means other configatron settings that I don't wont to reset ( such as my uptime start timestamp) will be reset as well.
So what is a better place to move my configatron.rb and load from so that it would allow for
loading once on startup and then changing some configs without and app restart?
Thanks.
i think that putting it in an initializer is the right place to store it.
if you want to update the configuration without restarting the application, you would normally setup a "watchdog". some process that pulls the database regulary to check for configuration updates. you could also implement some kind of callback that pushes changed configurations to your app.
when i put configatron to initializer, Rails environment variables load before loading configatron settings. As effect, middleware loaded in Rails configuration (config/environments/production.rb) was unable to use configatron variables.
so i ended up loading it as first thing in environment.rb instead
I am a former PHP developer learning Rails and Sinatra. In PHP, every page request loaded all of the required files. If I changed some code and refreshed the page, I could be sure that the code was fresh.
In Rails 3, Controller code is fresh on every request. However, if I modify any code in the /lib folder, I need to restart the server so the changes take effect.
Why does this happen? Is it something to do with the way Ruby is designed? Is Rails doing some optimizations to avoid reloading code on every request?
Thanks!
Edit: I am mostly interested in what is going on under the hood. Do frameworks like Rails and Sinatra do some special caching for classes? If so, what does they do? Is the default behavior in Ruby that all code gets reloaded on every request? Why do we need tools like Shotgun for Sinatra (http://sinatra-book.gittr.com/#automatic_code_reloading)?
While you are in development mode you should tell Rails not to cache your classes so they reload each time. This means that each request the classes are basically redefined in the rails interpreter. The setting in your Rails.root/config/environments/development.rb:
config.cache_classes = false
The classes the are in your lib/ dir are usually loaded through an initializer and not subject to this setting.
When you move to production you will want all of your classes to be cached so requests are faster and rails will do optimizations to things like scopes on your models.
You could put something in another initializer (maybe called Rails.root/config/initializers/development_reload.rb) that reloads the lib dir with every request in development (or just the ones you are working on):
# file development_reload.rb
if Rails.env.development?
ActionDispatch::Callbacks.after do
load 'filename_in_lib'
# or
Dir.entries("#{Rails.root}/lib").each do |entry|
load entry if entry =~ /.rb$/
end
end
end
I am calling "load" so it actually reloads the file, whereas "require" would just check if it has been loaded and determine it already has so it will not reload it. (I just threw this together and don't use it, but Ruby is extremely flexible and will allow you to do quite a bit.) Use something like this wisely and only in a dev environment.
Why code needs to be reloaded in Rails 3?
Ruby is an interpreted language (JRuby has some support for precompilation, but it's still interpreted). Interpreting the the definition of classes once on initialization is similar to compiling php and deploying in executable format (somewhat). The interpreter is not bothered with redefining classes all the time.
Forcing the explicit reload is an optimization for this type of interpreted language. (if you AOT compile in php you would need to reload the compiled "bytecode" after changes as well; default php uses on-the-fly compilation which is what you are taking advantage of)
How about a more high level approach:
ActionDispatch::Reloader.cleanup!
ActionDispatch::Reloader.prepare!
This was taken from Rails/ActiveRecord v3.2.13 - active_record/railtie.rb
The load approach didn't work for me. Just performing load caused a weird issue where it would trigger certain validators twice for me.
In order to fix that, I tried Object.send(:remove_const, User) before reloading User, but then I lost my observers on that class, so I started chasing my tail.
The above approach reloads all the classes, so maybe there is still yet a better approach to properly remove an individual class from cache and reload it...
At work, we have a situation where when
script/server
is run, then all the controller code is cached. This is to speed up the
development server. But that will mean that whenever we change the
controller code, we need to restart the server.
So we can turn off the caching of controller code all together. But
can't there be mechanism that is similar to the inclusion of javascript
foo.js?1275647624 <--- UNIX timestamp
which is to use the cached version as long as there is no code change,
but recompile it when there is code change?
Maybe because we use HAML and SASS a lot, loading some page (such as the
homepage of the site) can take 40 seconds on the dev environment and it
is quite long.
By default Rails will reload your classes for every request in the development environment. This should ensure that any changes are picked up. Classes are usually only cached when running in the production environment, or possibly if you have a staging environment set up.
Obviously I don't know your application, but 40 seconds to load a home page in development sounds like a long time. Are there any errors in the log?