KO | EN

GitLite

Minimalist Open Source Repository Search Engine

gitlite — search

#developer-tools #typescript #dsh #dsh-plugin #ai-agent #codex #ai-agents #deepseek-harness #claude-code #cli #react #mcp

postgres_ext-serializers

★ 323 Open GitHub ↗

No description available.

// repository documentation

Was this content helpful?

★ 0 (0 ratings)

# PostgresExt-Serializers

[![Build
Status](https://secure.travis-ci.org/DockYard/postgres_ext-serializers.png?branch=master)](https://travis-ci.org/DockYard/postgres_ext-serializers)
[![Code
Climate](https://codeclimate.com/github/dockyard/postgres_ext-serializers.png)](https://codeclimate.com/github/dockyard/postgres_ext-serializers)
[![Gem
Version](https://badge.fury.io/rb/postgres_ext-serializers.png)](https://badge.fury.io/rb/postgres_ext-serializers)

This Gem patches the ArraySerializer in Active Model Serializers to offload JSON serialization to PostgreSQL, which is much faster and more memory efficient than serialization in Ruby.

Instead of instantiating lots of ActiveRecord models, which are then serialized to a hash using ActiveModel Serializers and finally converted to JSON, this Gem builds the entire JSON in the database and returns it as a single string that can be passed through to the client unmodified.

## How does it work? ##

You can read [Avoid Rails When Generating JSON responses with PostgreSQL](https://dockyard.com/blog/2014/05/27/avoid-rails-when-generating-json-responses-with-postgresql) by Dan McClain on the DockYard Blog or [watch a YouTube video](https://www.youtube.com/watch?v=tYTw3Jshrqo) of his Postgres Open 2014 Talk [Using PostgreSQL, not Rails, to make Rails faster](http://slides.com/danmcclain/postgresopen-2014) (Slides) to understand how this Gem works under the hood.

## Supported Versions ##

This gem currently only works with the older active\_model\_serializers 0.8.x and activerecord 4.0/4.1/4.2. For activerecord 4.2 support you need at least postgres\_ext version 2.4.0.

You must be using at least Postgres 9.2, but 9.4 or later is recommended.

Support for newer AMS versions might be added in the future.

## Looking for help? ##

If it is a bug [please open an issue on
Github](https://github.com/dockyard/postgres_ext-serializers/issues). If you need
help using the gem please ask the question on
[Stack Overflow](http://stackoverflow.com). Be sure to tag the
question with `DockYard` so we can find it.

## Installation

Add this line to your application's Gemfile:

gem 'postgres_ext-serializers'

And then execute:

$ bundle

Or install it yourself as:

$ gem install postgres_ext-serializers

## Usage

Just `require 'postgres_ext/serializers'` and use
ActiveModel::Serializers as you normally would!
Postgres\_ext-serializers will take over anytime you try to serialize an
ActiveRecord::Relation.

### Methods in Serializers and Models

If you are using methods to compute properties for your JSON responses
in your models or serializers, postgres\_ext-serializers will try to
discover a SQL version of this call by looking for a class method with
the same name and the suffix `__sql`. Here's an example:

```ruby
class MyModel < ActiveRecord::Base
  def full_name
    "#{object.first_name} #{object.last_name}"
  end

def self.full_name__sql
    "first_name || ' ' || last_name"
  end
end

class MySerializer < ActiveModel::Serializer
  def full_name
    "#{object.first_name} #{object.last_name}"
  end

def full_name__sql
    "first_name || ' ' || last_name"
  end
end
```

There is no instance of MyModel created so sql computed properties needs to be
a class method. Right now, this string is used as a SQL literal, so be sure to
*not* use untrusted values in the return value.

### Note: Postgres date, timestamp or timestamptz format
Postgres 9.2 and 9.3 by default renders dates according to the current DateStyle
Postgres setting, but many JSON processors require dates to be in ISO 8601
format e.g. Firefox or Internet Explorer will parse string as invalid date with
default DateStyle setting. Postgres 9.4 onwards now uses ISO 8601 for JSON
serialization instead.

## Developing

To work on postgres\_ext-serializers locally, follow these steps:

1. Run `bundle install`, this will install (almost) all the development
    dependencies
 2. Run `gem install byebug` (not a declared dependency to not break CI)
 3. Run `bundle exec rake setup`, this will set up the `.env` file necessary to run
    the tests and set up the database
 4. Run `bundle exec rake db:create`, this will create the test database
 5. Run `bundle exec rake db:migrate`, this will set up the database tables required
    by the test
 6. Run `BUNDLE_GEMFILE='gemfiles/Gemfile.activerecord-4.2.x' bundle install --quiet` to create the Gemfile.lock.
 7. Run `bundle exec rake test:all` to run tests against all supported versions of Active Record (currently 4.0.x, 4.1.x, 4.2.x)

## Authors

Dan McClain [twitter](http://twitter.com/_danmcclain)
[github](http://github.com/danmcclain)

[We are very thankful for the many contributors](https://github.com/dockyard/postgres_ext-serializers/graphs/contributors)

## Versioning ##

This gem follows [Semantic Versioning](http://semver.org)

## Want to help? ##

Please do! We are always looking to improve this gem.

## Legal ##

[@dockyard](http://twitter.com/dockyard)

[Licensed under the MIT license](http://www.opensource.org/licenses/mit-license.php)

postgres_ext-serializers

Explore Similar Repositories

Was this content helpful?

Recent Feedback

Download README