Ruby On Rails Prerequisites
Contains the necessary basics to get you up to speed
Generating a controller
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$ rails generate controller StaticPages home help
Destroying a controller
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$ rails destroy controller StaticPages home help
Generating a model
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$ rails generate model User name:string email:string
Destroying a model
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$ rails destroy model User
Initiating a database migration
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$ rails db:migrate
Undoing a database migration
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#Undoing a single migration
$ rails db:rollback
#Go back all the way to the beginning
$ rails db:migrate VERSION=0
Test-driven development (TDD) is a valuable tool to have in your kit. Here are a set of guidelines on when we should test first (or test at all):
When a test is especially short or simple compared to the application code it tests, lean toward writing the test first.
When the desired behavior isn’t yet crystal clear, lean toward writing the application code first, then write a test to codify the result.
Because security is a top priority, err on the side of writing tests of the security model first.
Whenever a bug is found, write a test to reproduce it and protect against regressions, then write the application code to fix it.
Lean against writing tests for code (such as detailed HTML structure) likely to change in the future.
Write tests before refactoring code, focusing on testing error-prone code that’s especially likely to break.