Cheat Sheets are greate but they are not a substitute for learning the framework and reading the documentation as we most certainly have not covered every potential example here. Please refer to the Rails Command Line Docs for more information.

1. Rails Generate Scaffold With Foreign Key Of Life
2. Rails Generate Scaffold With Foreign Keys
3. Rails Generate Scaffold With Foreign Keyboard
4. Rails Scaffold With Foreign Key
5. Rails Generate Scaffold With Foreign Key Code
6. Rails Generate Scaffold With Foreign Key Examples
7. Rails Generate Scaffold With Foreign Key Set

Command Line Generator Info

You can get all of this information on the command line.

Removes the given foreign key from the table. Any option parameters provided will be used to re-add the foreign key in case of a migration rollback. It is recommended that you provide any options used when creating the foreign key so that the migration can be reverted properly. Removes the foreign key on accounts.branchid. The Rails Command LineAfter reading this guide, you will know: How to create a Rails application. How to generate models, controllers, database migrations, and unit tests. How to start a development server. How to experiment with objects through an interactive shell. The Rails Command LineAfter reading this guide, you will know: How to create a Rails application. How to generate models, controllers, database migrations, and unit tests. How to start a development server. How to experiment with objects through an interactive shell. Adds a new foreign key. Fromtable is the table with the key column, totable contains the referenced primary key. The foreign key will be named after the following pattern: fkrails. Identifier is a 10 character long string which is deterministically generated from the fromtable and column.

rails generate with no generator name will output a list of all available generators and some information about global options.rails generate GENERATOR --help will list the options that can be passed to the specified generator.

Ruby script/generate scaffold -skip-migration job jobid:string jobtitle:string minsalary:integer maxsalary:integer Note: The above command, beginning with ruby script/generate scaffold is a single continuous command. We need to indicate the primary key as we have done in the case of the employees table. Modify the file app/models/ job.rb. Nov 03, 2015  Sometimes after performing scaffold or before scaffold in rails it's become cumbersome that how to add drop-down in my scaffold. In this post we'll learn how to do it within few steps. Assume you have one model named 'User' and another as scaffold named 'Blog'. In model you have some predefined data with you. By starting the server rails s. Note that only one server can be up and running at one time. In the local development mode, how can you access the application you are working on. By going to 0.0.0.0 (which is your local machine) and listening to port 3000 (which is the rails port). So all in all localhost:3000 or 0.0.0.0:3000 (making sure the.

Rails Generate Examples

Create a Resource

Generate Models

Scaffold with ERB and API namespaced to /api/v1

Add Column to Existing Model

Column Types

Adding a Unique Property to a Field

Many to Many Relationship (Reference)

Remember that you do not want an id for the join table, so make sure to add :id => false t

If you use rails

you will have two indexes, but what you want is

For Rails 5 use create_join_table instead.

Adding Modifiers (Reference)

Modifiers are inserted through curly braces and they allow you to include things such as null and limit.

Add an age to a Friend with a limit

Add a price to a product with 2 decimals

Would result in a migration with a scale of 2 and percision of 10

Create a new model with a reference to another model (Reference)

Resulting migrations:

Polymorphism (Reference)

Suppose your building a collaborative app (like Pivotal Tracker and you want to add comments to projects, tasks, and attachments. You can do that by making comments polymorphic.

Column Defaults (Reference)

Default migration generator does not handle default values (column modifiers are supported but do not include default or null), but you could create your own generator.

You can also manually update the migration file prior to running rake db:migrate by adding the options to add_column:

.. and read Rails API

Rspec Generators

will create a new spec file in spec/models/widget_spec.rb

The same generator pattern is available for all specs:

Generating specific views

This tutorial assumes you have basic Rails knowledge from reading the Getting Started with Rails Guide.

1 Command Line Basics

There are a few commands that are absolutely critical to your everyday usage of Rails. In the order of how much you'll probably use them are:

• rails console
• rails server
• rails test
• rails generate
• rails db:migrate
• rails db:create
• rails routes
• rails dbconsole
• rails new app_name

You can get a list of rails commands available to you, which will often depend on your current directory, by typing rails --help. Each command has a description, and should help you find the thing you need.

Let's create a simple Rails application to step through each of these commands in context.

1.1 rails new

The first thing we'll want to do is create a new Rails application by running the rails new command after installing Rails.

You can install the rails gem by typing gem install rails, if you don't have it already.

Rails will set you up with what seems like a huge amount of stuff for such a tiny command! You've got the entire Rails directory structure now with all the code you need to run our simple application right out of the box.

1.2 rails server

The rails server command launches a web server named Puma which comes bundled with Rails. You'll use this any time you want to access your application through a web browser.

Dota 2 Beta Steam Key Generator How to install: 1. Download, extract and run.exe file, (If your antivirus blocking file, pause it or disable it for some time.) 2. Press Install button 3. Choose destination folder 4. Press Finish. How to Use: Open destination folder and locate file notes.txt, open it. Feb 18, 2012  ADOTA 2 CD Key Generator that will allow you to not only play the full version on release date, but also allow you to play the Dota 2 beta until it is released. Since Dota 2 was expected to be released this month, Steam already started making Dota 2 product codes, also known as serials and cd keys, that are redeemable on your Steam account. Dota 2 Beta Key Generator Free Download No Survey 2016 file is 100% clean and safe, no hidden ads or offers, we use only open source technologies, full code is available for you to edit or upate. Dota 2 Beta Key Generator Free Download No Survey 2016 supports wide range of. Dota 2 beta keys generator v3 2 exe. Dota 2 Beta CD Key Generator. DOTA 2 is a stand alone game using the Source engine with extra rendering modifications and departs from its simple modification status within Warcraft 3. It incorporates many of the same types of gameplay as DOTA with familiar heroes, levels, and multi player activity. Dota 2 Generator Key Free PROGamer Download Link has built in “Hide My Ass” VPN service, so you don’t need to be worried about you anonymity. Open source, safe and clean. All our files are based on open source technology, so our users can participate in developing this tool and make it more usable.

With no further work, rails server will run our new shiny Rails app:

With just three commands we whipped up a Rails server listening on port 3000. Go to your browser and open http://localhost:3000, you will see a basic Rails app running.

You can also use the alias 's' to start the server: rails s.

The server can be run on a different port using the -p option. The default development environment can be changed using -e.

The -b option binds Rails to the specified IP, by default it is localhost. You can run a server as a daemon by passing a -d option.

1.3 rails generate

The rails generate command uses templates to create a whole lot of things. Running rails generate by itself gives a list of available generators:

You can also use the alias 'g' to invoke the generator command: rails g.

You can install more generators through generator gems, portions of plugins you'll undoubtedly install, and you can even create your own!

Using generators will save you a large amount of time by writing boilerplate code, code that is necessary for the app to work.

Let's make our own controller with the controller generator. But what command should we use? Let's ask the generator:

All Rails console utilities have help text. As with most *nix utilities, you can try adding --help or -h to the end, for example rails server --help.

The controller generator is expecting parameters in the form of generate controller ControllerName action1 action2. Let's make a Greetings controller with an action of hello, which will say something nice to us.

What all did this generate? It made sure a bunch of directories were in our application, and created a controller file, a view file, a functional test file, a helper for the view, a JavaScript file, and a stylesheet file.

Check out the controller and modify it a little (in app/controllers/greetings_controller.rb):

Then the view, to display our message (in app/views/greetings/hello.html.erb):

Fire up your server using rails server.

The URL will be http://localhost:3000/greetings/hello.

With a normal, plain-old Rails application, your URLs will generally follow the pattern of http://(host)/(controller)/(action), and a URL like http://(host)/(controller) will hit the index action of that controller.

Rails comes with a generator for data models too.

For a list of available field types for the type parameter, refer to the API documentation for the add_column method for the SchemaStatements module. The index parameter generates a corresponding index for the column.

But instead of generating a model directly (which we'll be doing later), let's set up a scaffold. A scaffold in Rails is a full set of model, database migration for that model, controller to manipulate it, views to view and manipulate the data, and a test suite for each of the above.

We will set up a simple resource called 'HighScore' that will keep track of our highest score on video games we play.

The generator checks that there exist the directories for models, controllers, helpers, layouts, functional and unit tests, stylesheets, creates the views, controller, model and database migration for HighScore (creating the high_scores table and fields), takes care of the route for the resource, and new tests for everything.

Rails Generate Scaffold With Foreign Key Of Life

The migration requires that we migrate, that is, run some Ruby code (living in that 20130717151933_create_high_scores.rb) to modify the schema of our database. Which database? The SQLite3 database that Rails will create for you when we run the rails db:migrate command. We'll talk more about that command below.

Rails Generate Scaffold With Foreign Keys

Let's talk about unit tests. Unit tests are code that tests and makes assertionsabout code. In unit testing, we take a little part of code, say a method of a model,and test its inputs and outputs. Unit tests are your friend. The sooner you makepeace with the fact that your quality of life will drastically increase when you unittest your code, the better. Seriously. Please visitthe testing guide for an in-depthlook at unit testing.

Let's see the interface Rails created for us.

Go to your browser and open http://localhost:3000/high_scores, now we can create new high scores (55,160 on Space Invaders!)

1.4 rails console

The console command lets you interact with your Rails application from the command line. On the underside, rails console uses IRB, so if you've ever used it, you'll be right at home. This is useful for testing out quick ideas with code and changing data server-side without touching the website.

You can also use the alias 'c' to invoke the console: rails c.

You can specify the environment in which the console command should operate.

If you wish to test out some code without changing any data, you can do that by invoking rails console --sandbox.

1.4.1 The app and helper objects

Inside the rails console you have access to the app and helper instances.

With the app method you can access named route helpers, as well as do requests.

With the helper method it is possible to access Rails and your application's helpers.

1.5 rails dbconsole

rails dbconsole figures out which database you're using and drops you into whichever command line interface you would use with it (and figures out the command line parameters to give to it, too!). It supports MySQL (including MariaDB), PostgreSQL, and SQLite3.

You can also use the alias 'db' to invoke the dbconsole: rails db.

1.6 rails runner

Rails Generate Scaffold With Foreign Keyboard

runner runs Ruby code in the context of Rails non-interactively. For instance:

You can also use the alias 'r' to invoke the runner: rails r.

You can specify the environment in which the runner command should operate using the -e switch.

You can even execute ruby code written in a file with runner.

1.7 rails destroy

Think of destroy as the opposite of generate. It'll figure out what generate did, and undo it.

You can also use the alias 'd' to invoke the destroy command: rails d.

1.8 rails about

rails about gives information about version numbers for Ruby, RubyGems, Rails, the Rails subcomponents, your application's folder, the current Rails environment name, your app's database adapter, and schema version. It is useful when you need to ask for help, check if a security patch might affect you, or when you need some stats for an existing Rails installation.

1.9 rails assets:

You can precompile the assets in app/assets using rails assets:precompile, and remove older compiled assets using rails assets:clean. The assets:clean command allows for rolling deploys that may still be linking to an old asset while the new assets are being built.

If you want to clear public/assets completely, you can use rails assets:clobber.

1.10 rails db:

The most common commands of the db: rails namespace are migrate and create, and it will pay off to try out all of the migration rails commands (up, down, redo, reset). rails db:version is useful when troubleshooting, telling you the current version of the database.

More information about migrations can be found in the Migrations guide.

1.11 rails notes

rails notes searches through your code for comments beginning with a specific keyword. You can refer to rails notes --help for information about usage.

By default, it will search in app, config, db, lib, and test directories for FIXME, OPTIMIZE, and TODO annotations in files with extension .builder, .rb, .rake, .yml, .yaml, .ruby, .css, .js, and .erb.

1.11.1 Annotations

You can pass specific annotations by using the --annotations argument. By default, it will search for FIXME, OPTIMIZE, and TODO.Note that annotations are case sensitive.

1.11.2 Tags

You can add more default tags to search for by using config.annotations.register_tags. It receives a list of tags.

1.11.3 Directories

You can add more default directories to search from by using config.annotations.register_directories. It receives a list of directory names.

1.11.4 Extensions

You can add more default file extensions to search from by using config.annotations.register_extensions. It receives a list of extensions with its corresponding regex to match it up.

1.12 rails routes

Rails Scaffold With Foreign Key

rails routes will list all of your defined routes, which is useful for tracking down routing problems in your app, or giving you a good overview of the URLs in an app you're trying to get familiar with.

1.13 rails test

A good description of unit testing in Rails is given in A Guide to Testing Rails Applications

Rails comes with a test framework called minitest. Rails owes its stability to the use of tests. The commands available in the test: namespace helps in running the different tests you will hopefully write.

1.14 rails tmp:

The Rails.root/tmp directory is, like the *nix /tmp directory, the holding place for temporary files like process id files and cached actions.

The tmp: namespaced commands will help you clear and create the Rails.root/tmp directory:

• rails tmp:cache:clear clears tmp/cache.
• rails tmp:sockets:clear clears tmp/sockets.
• rails tmp:screenshots:clear clears tmp/screenshots.
• rails tmp:clear clears all cache, sockets, and screenshot files.
• rails tmp:create creates tmp directories for cache, sockets, and pids.

1.15 Miscellaneous

• rails stats is great for looking at statistics on your code, displaying things like KLOCs (thousands of lines of code) and your code to test ratio.
• rails secret will give you a pseudo-random key to use for your session secret.
• rails time:zones:all lists all the timezones Rails knows about.

1.16 Custom Rake Tasks

Custom rake tasks have a .rake extension and are placed inRails.root/lib/tasks. You can create these custom rake tasks with therails generate task command.

To pass arguments to your custom rake task:

You can group tasks by placing them in namespaces:

Invocation of the tasks will look like:

If you need to interact with your application models, perform database queries, and so on, your task should depend on the environment task, which will load your application code.

2 The Rails Advanced Command Line

More advanced use of the command line is focused around finding useful (even surprising at times) options in the utilities, and fitting those to your needs and specific work flow. Listed here are some tricks up Rails' sleeve.

2.1 Rails with Databases and SCM

When creating a new Rails application, you have the option to specify what kind of database and what kind of source code management system your application is going to use. This will save you a few minutes, and certainly many keystrokes.

Let's see what a --git option and a --database=postgresql option will do for us:

We had to create the gitapp directory and initialize an empty git repository before Rails would add files it created to our repository. Let's see what it put in our database configuration:

It also generated some lines in our database.yml configuration corresponding to our choice of PostgreSQL for database.

The only catch with using the SCM options is that you have to make your application's directory first, then initialize your SCM, then you can run the rails new command to generate the basis of your app.

Feedback

You're encouraged to help improve the quality of this guide.

Please contribute if you see any typos or factual errors. To get started, you can read our documentation contributions section.

Rails Generate Scaffold With Foreign Key Code

You may also find incomplete content or stuff that is not up to date. Please do add any missing documentation for master. Make sure to check Edge Guides first to verify if the issues are already fixed or not on the master branch. Check the Ruby on Rails Guides Guidelines for style and conventions.

Rails Generate Scaffold With Foreign Key Examples

If for whatever reason you spot something to fix but cannot patch it yourself, please open an issue.

Rails Generate Scaffold With Foreign Key Set

And last but not least, any kind of discussion regarding Ruby on Rails documentation is very welcome on the rubyonrails-docs mailing list.