Pager

Zero-dependency pagination for Ecto queries with automatic page boundary handling and flexible parameter types.

Features

• Clean API for paginating Ecto queries
• Handles string and integer page parameters seamlessly
• Automatic first page redirect when requested page is out of bounds
• Efficient count queries using subqueries
• Zero dependencies beyond Ecto
• Comprehensive pagination metadata

Installation

Add pager to your dependencies in mix.exs:

def deps do
  [
    {:pager, "~> 0.4.0"}
  ]
end

Usage

import Ecto.Query
alias YourApp.Repo
alias YourApp.Post

# Basic query pagination
query = from(p in Post)
result = Pager.page(query, Repo, 1, 20)

# Handle Phoenix params directly
def index(conn, %{"page" => page, "per_page" => per_page}) do
  query = from(p in Post, order_by: [desc: :inserted_at])
  pages = Pager.page(query, Repo, page, per_page)
  render(conn, "index.html", posts: pages.list)
end

Return Structure

%{
  has_next: true,          # More pages available
  has_prev: false,         # Previous pages available
  prev_page: 0,           # Previous page number
  page: 1,                # Current page
  next_page: 2,           # Next page number
  first: 1,               # First item index
  last: 20,               # Last item index
  count: 50,             # Total items
  list: [%Post{}, ...]   # Page items
}

Documentation

Documentation can be generated with ExDoc and published on HexDocs. Once published, the docs can be found at https://hexdocs.pm/page.

Contributing

1. Fork it
2. Create your feature branch (git checkout -b my-feature)
3. Commit your changes (git commit -am 'Add feature')
4. Push to the branch (git push origin my-feature)
5. Create a Pull Request

Development Setup

1. Create repo for tests:

   MIX_ENV=test mix ecto.create
   MIX_ENV=test mix ecto.migrate
   mix test