---
title: 'This Week in #dev (Jan 26, 2024)'
teaser: 'Inserting 100,000,000 rows into the database, how Turbo can break OAuth forms,
  and more!

  '
tags: this week in dev,rails,databases,hotwire
author: thoughtbot
published_on: 2024-02-05
---

Welcome to another edition of [This Week in #dev](https://thoughtbot.com/blog/tags/this-week-in-dev), a series of posts
where we bring some of our most interesting Slack conversations to the public.

## Loading Data into MySQL Quickly

[Matheus Richard][matheus] shared a [video about loading 100,000,000 rows into a
MySQL database][video]. In particular, he highlights the use of [MySQL's LOAD
DATA] statement, which is a very fast way to load data from a file into a table.

```sql
-- Example:
LOAD DATA INFILE 'data.txt' INTO TABLE tbl_name
  FIELDS TERMINATED BY ',' ENCLOSED BY '"'
  LINES TERMINATED BY '\r\n'
  IGNORE 1 LINES;
```

[video]: https://www.youtube.com/watch?v=rP0lZ_T5P28
[MySQL's LOAD DATA]: https://dev.mysql.com/doc/refman/8.0/en/load-data.html
[matheus]: https://thoughtbot.com/blog/authors/matheus-richard

## Rails' `prepend_before_action`

[Steve Polito][spolito] shared a discovery in Ruby on Rails: the
[`prepend_before_action` method]. It allows you to call a method before another
controller action (can be useful when dealing with a `before_action` that is shared between controllers).

Here's a contrived example:

```rb
class Namespace < ApplicationController
  before_action :authorize_request

  def authorize_request
    true
  end
end

class Namespace::Nested < Namespace
  before_action :set_user

  def set_user
    @user = User.find(params[:id])
  end

  # 🚨
  # We don't have access to @user yet
  # because :authorize_request is called first
  def authorize_request
    @user.admin?
  end
end
```

With `prepend_before_action`, we can call `:set_user` before
`:authorize_request`:

```rb
class Namespace < ApplicationController
  before_action :authorize_request

  def authorize_request
    true
  end
end

class Namespace::Nested < Namespace
  # ✅
  # prepend_before_action will call this method
  # before it calls :authorize_request
  prepend_before_action :set_user

  def set_user
    @user = User.find(params[:id])
  end

  def authorize_request
    @user.admin?
  end
end
```

[`prepend_before_action` method]: https://api.rubyonrails.org/classes/AbstractController/Callbacks/ClassMethods.html#method-i-prepend_before_action
[spolito]: https://thoughtbot.com/blog/authors/steve-polito

## Turbo & OAuth Forms

[Joël Quenneville][joelq] discovered that Turbo can cause issues with OAuth
forms due to CORS restrictions. In his experience, including Turbo in a client's
login page broke the "sign in with Google" button. Fortunately, the solution was
simple: [disabling Turbo drive] either locally by adding a `data-turbo="false"`
attribute in the HTML or globally by setting `Turbo.session.drive = false` in
the JS.

[joelq]: https://thoughtbot.com/blog/authors/joel-quenneville
[disabling Turbo drive]: https://turbo.hotwired.dev/handbook/drive#disabling-turbo-drive-on-specific-links-or-forms

## Removing blank values from Enumerables

[Steve Polito][spolito] discussed the use of `compact` in Ruby to remove `nil`
values from a hash. However, `compact` does not account for empty strings or
hashes. To address this, he used [Rails' `compact_blank`], which removes `nil`,
empty strings, and empty hashes from an Enumerable.

```rb
[1, "", nil, 2, " ", [], {}, false, true].compact_blank
# =>  [1, 2, true]
```

[spolito]: https://thoughtbot.com/blog/authors/steve-polito
[Rails' `compact_blank`]: https://api.rubyonrails.org/classes/Enumerable.html#method-i-compact_blank

## Thanks

This edition was brought to you by [Joël Quenneville][joelq], [Matheus
Richard][matheus], and [Steve Polito][spolito]. Thanks to all contributors! 🎉