Use rails runner. Place scripts in the scripts
folder,
then:
./bin/rails runner script/backfill.rb --environment=production
my_model.new_record?
id
It’s not enough to specify the param in
config/routes.rb
, such as:
resources :projects, param: :my_uuid
I also have to set
class Project < ApplicationRecord
def to_param
my_uuid
end
end
has_one
gotchaIf model A has_one
B, and you use:
b = a.build_b()
Any existing a.b
is quietly deleted, and this occurs
even if the new b
does not pass validation.
Use variadic call instead of passing an array. Note the rogue
%2F
:
(ruby) project_device_check_configuration_path([@project, @device_check_configuration])
# => "/projects/abdbf565%2F/device_check_configuration"
versus
(ruby) project_device_check_configuration_path(@project, @device_check_configuration)
# => "/projects/abdbf565/device_check_configuration"
Rails uses transactions by default in test cases. If I breakpoint
inside a test and inspect the the contents of the
test DB in a mysql client, I find no records. To temporarily disable
transactions so that I can inspect DB contents, use:
class MyTest < ActiveSupport::TestCase
self.use_transactional_tests = false
# ...
end
class ProjectUIModel
include ActiveModel::API
attr_accessor :name
validates_presence_of :name
end
I wanted this to use the rails (ActionPack) form helpers with a UI
model.
See the full API description at
~/.rvm/gems/ruby-3.2.2/gems/activemodel-7.1.3.4/README.rdoc
Model.includes(:my_association).first
Nested:
Model.includes([first_level: [second_level: :third_level]])
For has_many
and variants, use
my_model.my_associations.build(...)
# or
my_model.my_associations.create(...)
For has_one
use
my_model.build_my_association(...)
# or
my_model.create_my_association(...)
Run validations and callbacks:
my_model.update(some_field: 1)
Skip validations and callbacks:
my_model.update_attribute(:some_field, 1)
my_model.to_json(include: { my_association: {}})
or
ActiveSupport::JSON.encode(my_model, include: { my_association: {}})
migration_version = 20240603120712 # Replace with your specific migration version
migration_context = ActiveRecord::MigrationContext.new('db/migrate', ActiveRecord::SchemaMigration)
migration_context.run(:down, migration_version)
migration_context.run(:up, migration_version)
Related: to quiet the logs when running migrations programmatically, especially if inserting a bunch of seed data, use:
ActiveRecord::Schema.verbose = false
Source: https://stackoverflow.com/a/69011649/143447
https://github.com/rails/rails/issues/51910#issuecomment-2130296578
-skip-tests --skip-jbuilder
validate do
errors.add(:some_field, 'Error message') unless my_condition
end
Or
validate :something_custom
private
def something_custom
if my_condition
errors.add(:some_field, "Error message")
end
end
In the action that I’m serving the partial page contents from, remember to skip layout rendering:
def my_action
# Define my_action.html.erb and populate it with partial contents
render :layout => false
end
In the UI element that kicks off the fetch of partial content, specify the turbo frame to update:
<%= turbo_frame_tag “frame-to-update” do %>
Placeholder
<% end %>
<%= link_to ‘Update partial contents’, my_action_path, data: {turbo_method: :get, turbo_frame: “frame-to-update” } %>
Or, without rails form helpers:
<turbo-frame id="frame-to-update">
Placeholder
</turbo-frame>
<a data-turbo-method="get" data-turbo-frame="frame-to-update" href="<%= my_action_path %>">Update partial contents</a>
rails --tasks
Gemfile
to use the latest versionrails app:update
config/initializers/new_framework_default*
Use the after_save
hook. Say the model has an attribute
called name
,
inside the hook use name_before_last_save
to get the
previous value.
journalctl -fu puma
I have accidentally rolled back farther than intended, and then I
have a production data fill on my hands.
Instead, make sure I use STEP=1
. Or better yet be explicit
with:
rake db:migrate:down VERSION=20240303...
Then, to go the other direction:
rake db:migrate:up VERSION=20240303...
Or:
rake db:migrate:redo VERSION=20240303...
RAILS_ENV=production ./bin/rails db:migrate:status
The schema_migrations
table:
MariaDB [aiproxy_production]> select * from schema_migrations;
Careful with this. It will not modify the
schema_migrations
table:
./bin/rails c --environment=production
require "./db/migrate/20240303150054_create_dynamo_tokens_table.rb"
CreateDynamoTokensTable.new.down
activemodel-7.0.7/lib/active_model/validations/validates.rb line 106
my_model.errors.full_messages
Occassionally I find myself needing to do this:
rm aiproxy/dashboard/tmp/pids/server.pid
pkill puma
If that doesn’t work, try:
lsof -i :3000
:: find the ruby process
kill -9 <id>
Or
ps aux | grep puma | grep -v grep | awk '{print $2}' | xargs kill
Follow these instructions to get rid of all the
/rails/conductor/action_mailbox
routes:
https://www.youtube.com/watch?v=IDsYWrsmO9g
Run rails tmp:clear
and remove everything in
public/assets
class Router
include Rails.application.routes.url_helpers
def self.default_url_options
ActionMailer::Base.default_url_options
end
end
Then use `Router.new.my_model_url(@my_model)`
Source: https://stackoverflow.com/a/54542949/143447
Button:
<%= button_to "Delete", @my_model, form: { data: { turbo_confirm: "Are you sure?" } }, method: :delete %>
Link:
<%= link_to "Delete", my_path, data: {turbo_method: :delete, turbo_confirm: 'Are you sure?'} %>
render :text
is no longer a thing. Use
render plain: "hi"
instead
Start the server with ./bin/rails s -b 0.0.0.0
Use the following to get my 192.168 IP:
ifconfig | grep 'inet '
Browse to 192.168.X.Y:3000
This is no longer possible in Rails 7:
link_to "Remove something", my_path, method: :delete
Instead, turbo must be used:
link_to "Remove something", my_path, data: { turbo_method: :delete }
Or, use a form instead:
<%= button_to "Destroy", @my_model, method: :delete %>
Or, write a data-turbo-method
attribute on the html with
the desired verb (post in this case):
<a data-turbo-method="post" href="/users?color=red">enter as red</a>
cd <my-proj>
vim "$(bundle show actioncable)/app/assets/javascripts/actioncable.esm.js"
:: restart rails server after making modifications!
./bin/rails c --environment=production
irb> r = Redis.new
irb> r.ping
=> "PONG"
Add an indexed column to the db with one generator:
rails g migration add_index_to_rooms uuid:string:index
View the ActionCable activity at Dev tools > Network > Tap on cable > WS tab > Response subtab
View importmap with:
./bin/importmap json
Keep playing with syntax in config/importmap.rb until
importmap json
shows the importmaps I expect.
Pin an external dependency with:
./bin/importmap pin <dep-name>
Add to importmap:
./bin/importmap pin jquery
Modify application.js to include:
import jquery from "jquery"
window.$ = jquery
window.jQuery = jquery
https://www.youtube.com/watch?v=mpWFrUwAN88
Highlights:
Add this stylesheet to application.html.erb
<link rel=“stylesheet” href=“https://cdn.simplecss.org/simple.min.css"\>
Get a rich editor out of the box with
rails action_text:install
Adding js deps is slick
./bin/importmap pin <package-name>
, at 10:50
--download
Generator with foreign key, references, at 15:00
Example of form_with
for child resource at 17:25
form_with model: [post, Comment.new] do |form|
Email previews from mailer (text and html) at 22:30
Hotwire intro starts at 25:00
broadcasts_to :post
will
automatically broadcast creates, updates, and destroysChange from one db to another with
rails db:system:change --to=postgresql
Set up the cable so that it streams to the current user:
// app/channels/application_cable/connection.rb
// Source: https://guides.rubyonrails.org/action_cable_overview.html
module ApplicationCable
class Connection < ActionCable::Connection::Base
include ActionController::Cookies
identified_by :current_user
def connect
self.current_user = find_verified_user
end
def disconnect
puts "#{self.class} Disconnected"
end
private
def find_verified_user
if verified_user = User.find_by_id(cookies.encrypted['_YOUR_APP_NAME_session']['user_id'])
verified_user
else
reject_unauthorized_connection
end
end
end
end
// my_channel.rb
class MyChannel < ApplicationCable::Channel
def subscribed
stream_for current_user
end
...
end
Send notifications to specific user:
// https://stackoverflow.com/a/43943322/143447
MyChannel.broadcast_to(user, { notification: 'Test message' })
Get all cables for a specific user:
ActionCable.server.remote_connections.where(current_user: current_user)
Question to experiment with:
Is the web socket torn down when navigating between pages?
URL helpers are not available by default in ActionCable.
Use this:
class MyChannel < ApplicationCable::Channel
include Rails.application.routes.url_helpers
Generator to create actions in a channel:
rails g channel <channel-name> <action-name>
This modifies the import map at config/importmap.rb to add the
actioncable dependency as an esm module,
and modifies app/javascript/application to import everything under the
app/javascript/channels dir.
I can get a reference to a connected cable by modifying
<channel-name>_channel.js
to contain:
window.myChannel = consumer.subscriptions.create("MyChannel", { ...
Restart the rails server, refresh firefox, open dev tools
(cmd+opt+i), tap network, tap WS.
There will be a connected web socket.
Open the console, I can send <action-name>
with:
myChannel.<action-name>()
For example, following the DHH tutorial for action cable, if I use
the generator rails g channel room speak
, I can:
myChannel.speak()
Add an argument by modifying the speak
definition in
room_channel.js
. E.g.
// room_channel.js
speak: function(message) {
return this.perform('speak', message);
}
then on ruby side:
// room_channel.rb
def subscribed
stream_from "room_channel"
end
def speak(cable_data)
puts "Room channel received #{cable_data['message']}; echoing..."
ActionCable.server.broadcast 'room_channel', {message: cable_data['message']}
end
and back on client:
// room_channel.js
received(data) {
alert(data['message'])
},
finally, punching
myChannel.speak({message: "hello world"})
into the dev
tools console should pop an alert message.
There is also a bit of this vid (16:40) where he shows that UI can be updated from an async job using ActionCable. (background job, async job, actioncable, action cable)
Source for Rails 5 ActionCable demo (DHH): https://www.youtube.com/watch?v=n0WUjGkDFS0
My stackoverflow question: https://stackoverflow.com/questions/76964623/what-is-the-equivalent-of-app-cable-for-rails-7
See ~/dev/actioncable_experiment
Clip from hotwire demo:
“Turbo streams deliver page changes over web sockets or in response to
form
submissions using just html and a set of crud-like action tags. The tags
let
you append, prepend, or replace and remove any target dom element from
the
existing page. They’re strictly limited to DOM changes though, no
direct
javascript invocations. If you need more than DOM change, connect a
stimulus
controller.” minute 5 here: https://www.youtube.com/watch?v=eKY-QES1XQQ
You can think of it this way: just like the class attribute is a bridge connecting HTML to CSS, Stimulus’s data-controller attribute is a bridge connecting HTML to JavaScript.
https://stimulus.hotwired.dev/handbook/introduction
Do not try to set an environment variable for environment! This:
RAILS_ENV=development EDITOR='vim' bin/rails credentials:edit
is not the same as this:
EDITOR='vim' bin/rails credentials:edit --environment=development
Edit credentials with:
rails credentials:edit --environment=development
Environment credentials are stored at:
config/credentials/<environment>.yml.enc
Environment credentials key is stored at (do not check this in!):
config/credentials/<environment>.key
If I edit development credentials:
./bin/rails credentials:edit --environment=development
stripe:
publishable_key: <snip>
secret_key: <snip>
I can reference the secret at runtime with:
Rails.application.credentials.stripe.secret_key
The master key is stored at (do not check this in!):
config/master.key
Change master key: https://stackoverflow.com/a/59993704/143447
In production, running this:
EDITOR="/usr/bin/vim" bin/rails credentials:edit
changes the file contents at config/credentials.yml.enc
I prefer not to use credentials:edit
without an
environment,
instead relying upon config/credentials/development.*
and
config credentials/production.*
If in production I get the error:
ArgumentError: Missing `secret_key_base` for 'production' environment, set this string with `bin/rails credentials:edit`
Either create an env variable called SECRET_KEY_BASE
or
add secret_key_base
to production.yml.enc with:
./bin/rails credentials:edit --environment=production
Rails.application.credentials.config
I don’t understand how this works.
Why does ./bin/rake secret
dump a different secret to the
console each time?
Oh, it is not dumping secret_key_base
, it is just spitting
out a random string for use as a secret.
See the task description with rake -T secret
Read ./bin/rails credentials:help
In development and testing,
Rails.application.secrets.secret_key_base
is derived from
the app name.
In production, I add secret_key_base
to
production.yml.enc
To serve at https://localhost without host blocking,
add config.hosts.clear to config/environments/development.rb