If we enter a `connected_to` block and call `establish_connection` like
the test added here we need to ensure that `shard: current_shard` is passed
to the handler, otherwise the connection will be established on
`default` not on `shard_one`.
Co-authored-by: NJohn Crepezzi <john.crepezzi@gmail.com>

Rename test models for inclusivity

After renaming `Man` to `Human` the variable letter `m` in these tests
ends up being pretty confusing. Rather than rename it to `h`, this
commit replaces it with the full word `human`.

Since I was already renaming things, I also went ahead and replaced `f`
with `face`, `i` with `interest`, and `a` with `author`.

The commit replaces the `Man` model used in tests with a `Human` model. It
also replaces the existing `Human` model with a `SuperHuman` model
inheriting from `Human`.

While this may seem like a cosmetic change, I see it as more of an
inclusivity change. I think it makes sense for a number of reasons:

* Prior to this commit the `Human` model inherited from `Man`. At best
  this makes no sense (it should be the other way around). At worst it
  is offensive and harmful to the community.
* It doesn't seem inclusive to me to have exclusively male-gendered
  examples in the codebase.
* There is no particular reason for these examples to be gendered.
* `man` is hard to grep for, since it also matches `many, manager,
  manual, etc`

For the most part this is a simple search and replace. The one exception
to that is that I had to add the table name to the model so we could use
"humans" instead of "humen".

Follow-up to #40013.

Newly created `Blob`s may not be uploaded yet, so do not try to update
their service metadata.

Adds documentation for habtm association always being optional: true [ci skip]

parent f4471fc7
author Sandip Mane <sandip.mane@bigbinary.com> 1593247595 +0530
committer Sandip Mane <sandip2490@gmail.com> 1597253412 +0530

Adds doc for habtm association for always optional: true

Added docs line under definition of habtm with a text containing habtm refers to zero or more associations

Added docs line under definition of habtm with a text containing it refers to zero or more associations

Updated the sentence to include declaring association for habtm relation

Add baseline defaults section [ci skip]

[ci skip] Add clarity on protect_from_forgery documentation

Address `ArgumentError: Missing host to link to! Please provide the :host parameter, set default_url_options[:host], or set :only_path to true`

Address `ArgumentError: Missing host to link to! Please provide the :host parameter, set default_url_options[:host], or set :only_path to true`

This pull request fixes #38697

It is caused by `@controller.singleton_class.include @routes.url_helpers` when `@controller` is nil in `ActionController::TestCase`.

* Without this commit

```ruby
% cd actionview
% PARALLEL_WORKERS=1 bin/test test/actionpack/controller/layout_test.rb test/template/url_helper_test.rb --seed 16702 -n "/^(?:LayoutSetInResponseTest#(?:test_layout_symbol_set_in_controller_returning_nil_falls_back_to_default)|UrlHelperTest#(?:test_url_for_with_array_and_only_path_set_to_false))$/"

Run options: --seed 16702 -n "/^(?:LayoutSetInResponseTest#(?:test_layout_symbol_set_in_controller_returning_nil_falls_back_to_default)|UrlHelperTest#(?:test_url_for_with_array_and_only_path_set_to_false))$/"

.E

Error:
UrlHelperTest#test_url_for_with_array_and_only_path_set_to_false:
ArgumentError: Missing host to link to! Please provide the :host parameter, set default_url_options[:host], or set :only_path to true
    /Users/yahonda/src/github.com/rails/rails/actionpack/lib/action_dispatch/http/url.rb:64:in `full_url_for'
    /Users/yahonda/src/github.com/rails/rails/actionpack/lib/action_dispatch/http/url.rb:54:in `url_for'
    /Users/yahonda/src/github.com/rails/rails/actionpack/lib/action_dispatch/routing/route_set.rb:333:in `block in <class:RouteSet>'
    /Users/yahonda/src/github.com/rails/rails/actionpack/lib/action_dispatch/routing/route_set.rb:838:in `url_for'
    /Users/yahonda/src/github.com/rails/rails/actionpack/lib/action_dispatch/routing/route_set.rb:270:in `call'
    /Users/yahonda/src/github.com/rails/rails/actionpack/lib/action_dispatch/routing/route_set.rb:213:in `call'
    /Users/yahonda/src/github.com/rails/rails/actionpack/lib/action_dispatch/routing/route_set.rb:326:in `block in define_url_helper'
    /Users/yahonda/src/github.com/rails/rails/actionpack/lib/action_dispatch/routing/polymorphic_routes.rb:233:in `polymorphic_method'
    /Users/yahonda/src/github.com/rails/rails/actionpack/lib/action_dispatch/routing/polymorphic_routes.rb:116:in `polymorphic_url'
    /Users/yahonda/src/github.com/rails/rails/actionview/lib/action_view/routing_url_for.rb:104:in `url_for'
    /Users/yahonda/src/github.com/rails/rails/actionview/test/template/url_helper_test.rb:102:in `test_url_for_with_array_and_only_path_set_to_false'

bin/test test/template/url_helper_test.rb:100

Finished in 0.042275s, 47.3093 runs/s, 47.3093 assertions/s.
2 runs, 2 assertions, 0 failures, 1 errors, 0 skips
%
```

Update security.md to note that CSRF security token is included in requests automatically when `config.action_controller.default_protect_from_forgery` is set to `true`, which is the default for newly created Rails applications.

fix: warning: instance variable @controller not initialized
Co-authored-by: NSamuel Williams <samuel.williams@oriontransfer.co.nz>

An Active Storage `Blob` must be identified before it can be reliably
validated.  For direct uploads, a `Blob` is identified when it is
attached, rather than when it is created.

Before this commit, the sequence of events when attaching a `Blob` was:

1. Find the `Blob`.
2. Assign the `Blob` to an `Attachment`.
3. Save the owner record.
4. Save the `Attachment`.
5. Identify the `Blob`'s true `content_type` from its file.
6. Save the `Blob`.

This meant that the owner record's validations might not see the
`Blob`'s true `content_type`.

After this commit, the sequence of events will be:

1. Find the `Blob`.
2. Identify the `Blob`'s true `content_type` from its file.
3. Assign the `Blob` to an `Attachment`.
4. Save the owner record.
5. Save the `Attachment`.
6. Save the `Blob`.

Thus the `Blob`'s true `content_type` will be available when running the
owner record's validations.

Document dbconsole command for multiple database [ci skip]

Fixes #39937

Fix `assert_recognizes` on mounted root routes.

Fix missed establish_connection

Allow `assert_recognizes` routing assertions to work on mounted root routes.

In `connected_to` one of the deprecated arguments wasn't well tested so
the incorrect methods signature wasn't caught by the tests.

This change updates the caller when `connected_to` uses the database
key.

I've also cleaned up a few arguments that weren't necessary. Since
the handler methods set defaults for the `shard` key, we don't need to
pass that in `establish_connection` when not using the sharding API.

Add helper method for resetting connection handlers in tests

This change makes a helper method for resetting connection handlers in
the Active Record tests. The change here is relatively small and may
seem unnecessary. The reason we're pushing this change is for upcoming
refactoring to connection management. This change will mean that we can
update one location instead of 9+ files to reset connections. It will
reduce the diff of our refactoring and make reusing this code easier in
the future.

The method name chosen is purposefully `clean_up_connection_handler`
over `clean_up_connection_handlers` because in the future there will
only be one handler.
Co-authored-by: NJohn Crepezzi <john.crepezzi@gmail.com>

Rename `pool_key` to `shard` and use kwargs for connection methods

Fix incorrect result when eager loading with duplicated through association with join scope

Remove unnecessary with_temporary_connection_pool calls

This change ensures that the connection methods are using kwargs instead
of positional arguments. This change may look unnecessary but we're
working on refactoring connection management to make it more robust and
flexible so the method signatures of the methods changed here will
continue to evolve and change.

This commit does not change any released public APIs. The `shard` and
`owner_name` arguments were added in 6.1 which is not released yet.
Using kwargs will allow these methods to be more flexible and not get
super ugly as we change their underlying behavior. The kwargs let us
support multiple non-positional arguments with default.
Co-authored-by: NJohn Crepezzi <john.crepezzi@gmail.com>

This change renames the following:

* `current_pool_key` -> `current_shard`
* `default_pool_key` -> `default_shard`
* `pool_key` -> `shard`

Originally we had intended to name the `shard` as `pool_key` because
when we implemented the internal private API we weren't sure how it was
going to be used for sharding and wanted to implement behavior without
promising a public API. Now that we have a public API for sharding it's
better to use the same name everywhere rather than have one name for
private APIs and one name for public APIs. This should make
contributions and tracking down bugs easier in the future.

This PR doesn't require any deprecations because the sharding API is
unreleased and so is all the internal code that was using `pool_key`.
Co-authored-by: NJohn Crepezzi <john.crepezzi@gmail.com>

While debugging a different problem I'm working on I realized that this
method `with_temporary_connection_pool` isn't necessary in most of the
cases we're using it for.

Anywhere we establish new connections inside the block won't throw away
those new connections. I also removed this from places that can use the
existing connection and don't need a new temporary pool. I'm not sure if
this file was using it in many places because of copy / paste or real
issues that are no longer present.

Fix deserializing enum mapping nil

I had found the issue while working on fixing #33525.

That is if duplicated association has a scope which has `where` with
explicit table name condition (e.g. `where("categories.name": "General")`),
that condition in all duplicated associations will filter the first one
only, other all duplicated associations are not filtered, since
duplicated joins will be aliased except the first one (e.g.
`INNER JOIN "categories" "categories_categorizations"`).

```ruby
class Author < ActiveRecord::Base
  has_many :general_categorizations, -> { joins(:category).where("categories.name": "General") }, class_name: "Categorization"
  has_many :general_posts, through: :general_categorizations, source: :post
end

authors = Author.eager_load(:general_categorizations, :general_posts).to_a
```

Generated eager loading query:

```sql
SELECT "authors"."id" AS t0_r0, ... FROM "authors"

-- `has_many :general_categorizations, -> { joins(:category).where("categories.name": "General") }`
LEFT OUTER JOIN "categorizations" ON "categorizations"."author_id" = "authors"."id"
INNER JOIN "categories" ON "categories"."id" = "categorizations"."category_id" AND "categories"."name" = ?

-- `has_many :general_posts, through: :general_categorizations, source: :post`
---- duplicated `through: :general_categorizations` part
LEFT OUTER JOIN "categorizations" "general_categorizations_authors_join" ON "general_categorizations_authors_join"."author_id" = "authors"."id"
INNER JOIN "categories" "categories_categorizations" ON "categories_categorizations"."id" = "general_categorizations_authors_join"."category_id" AND "categories"."name" = ? -- <-- filtering `"categories"."name" = ?` won't work
---- `source: :post` part
LEFT OUTER JOIN "posts" ON "posts"."id" = "general_categorizations_authors_join"."post_id"
```

Originally eager loading with join scope didn't work before Rails 5.2
(#29413), and duplicated through association with join scope raised a
duplicated alias error before alias tracking is improved in 590b045e.

But now it will potentially be got incorrect result instead of an error,
it is worse than an error.

To fix the issue, it makes eager loading to deduplicate / re-use
duplicated through association if possible, like as `preload`.

```sql
SELECT "authors"."id" AS t0_r0, ... FROM "authors"

-- `has_many :general_categorizations, -> { joins(:category).where("categories.name": "General") }`
LEFT OUTER JOIN "categorizations" ON "categorizations"."author_id" = "authors"."id"
INNER JOIN "categories" ON "categories"."id" = "categorizations"."category_id" AND "categories"."name" = ?

-- `has_many :general_posts, through: :general_categorizations, source: :post`
---- `through: :general_categorizations` part is deduplicated / re-used
LEFT OUTER JOIN "posts" ON "posts"."id" = "categorizations"."post_id"
```

Fixes #32819.

Follow up to #38086.

User assigned nil is type casted by #38086, but loaded nil from database
does not yet, this fixes that.

Make `Enumerable.pluck` faster for single key

Directly `klass.new` is clear enough than factory methods.

Update GitHub gist api link and fix documentation in api_app guide [ci skip]

The GitHub gist API page is out of date. This commit replaces it with
the new link.

Also, removed unnecessary commas, added missing fullstop and fixed
a ruby snippet which wasn't rendered correctly before.

Get rid of the unused RuntimeRegistry.connection_handler

It's no longer used since https://github.com/rails/rails/commit/5ce3e022ef136324d288fb493e0938e76a74981a