FatEcto

Description

FAT provides methods for dynamically building queries depending on the parameters it receive.

Currently it's supporting following query functions:

• where
• select
• joins
• order_by
• include
• group_by

Installation

you can get latest from github or published version from hex

{:fat_ecto, github: "tanweerdev/fat_ecto"}
or
{:fat_ecto, "~> 0.1"}

Please do not pass custom $join type for associations which are related via has_many or many_to_many eg

# Please dont pass join like below to avoid un-expected/duplicated records
"$include": %{"doctors" => %{"$join" => "left"}}
# correct way
"$include": %{"doctors" => %{}}

Config

config :my_app, :fat_ecto,
  repo: ExApi.Repo,
  default_limit: 10,
  max_limit: 100

Usage

Once installed you can use FatEcto.FatQuery inside your module and use the build method. Which is the entry method for building every query. And also the main method for the FatEcto.FatQuery.

build(schema_name, params)

Example

defmodule MyApp.Query do
  use FatEcto.FatQuery, otp_app: :my_app, max_limit: 103, default_limit: 34
end

import MyApp.Query
query_opts = %{
      "$select" => %{
        "$fields" => ["name", "location", "rating"],
        "fat_rooms" => ["beds", "capacity"]
      },
      "$order" => %{"id" => "$desc"},
      "$where" => %{"rating" => 4},
      "$group" => ["total_staff", "rating"],
      "$include" => %{
        "fat_doctors" => %{
          "$include" => ["fat_patients"],
          "$where" => %{"name" => "ham"},
          "$order" => %{"id" => "$desc"},
          "$join" => "$right"
        }
      },
      "$right_join" => %{
        "fat_rooms" => %{
          "$on_field" => "id",
          "$on_table_field" => "hospital_id",
          "$select" => ["beds", "capacity", "level"],
          "$where" => %{"incharge" => "John"},
          "$order" => %{"level" => "$asc"}
        }
      }
    }
iex> build(FatEcto.FatHospital, query_opts)
iex> #Ecto.Query<from f0 in FatEcto.FatHospital, right_join: f1 in "fat_rooms",
     on: f0.id == f1.hospital_id, right_join: f2 in assoc(f0, :fat_doctors),
     where: f0.rating == ^4 and ^true, where: f1.incharge == ^"John" and ^true,
     group_by: [f0.total_staff], group_by: [f0.rating], order_by: [asc: f1.level],
     order_by: [desc: f0.id],
     select: merge(map(f0, [:name, :location, :rating, :id, {:fat_rooms, [:beds, :capacity]}]),
     %{^:fat_rooms => map(f1, [:beds, :capacity, :level])}),
     preload: [fat_doctors: #Ecto.Query<from f0 in FatEcto.FatDoctor,
     left_join: f1 in assoc(f0, :fat_patients),
     where: f0.name == ^"ham" and ^true, order_by: [desc: f0.id],
     limit: ^10, offset: ^0, preload: [:fat_patients]>]>

Options:

These are the options supported

see Docs for more details.