# EctoPGMQ
[](https://hex.pm/packages/ecto_pgmq)
An opinionated [PGMQ](https://github.com/pgmq/pgmq) client for Elixir.
## Installation
This package can be installed by adding `:ecto_pgmq` to your list of
dependencies in `mix.exs`:
```elixir
defp deps do
[
# Should already be present if you're using Ecto
{:ecto_sql, "~> 3.11"},
{:postgrex, ">= 0.0.0"},
# Required to use the EctoPGMQ.Producer module
{:broadway, "~> 1.0"},
{:ecto_pgmq, "~> 1.0"}
]
end
```
## Documentation
For additional documentation, see
[HexDocs](https://hexdocs.pm/ecto_pgmq/readme.html).
## Usage
`EctoPGMQ` is designed to be used seamlessly with your application repo. Some
common operations are showcased below but the full feature-space can be found in
the [Documentation](#documentation).
### Installing the PGMQ Extension
The most common way to install the PGMQ extension is in a database migration. We
can create a database migration with the following command:
```bash
mix ecto.gen.migration create_pgmq
```
We can then implement the migration accordingly:
```elixir
defmodule MyApp.Repo.Migrations.CreatePgmq do
use Ecto.Migration
alias EctoPGMQ.Migrations
def change, do: Migrations.create_extension()
end
```
For more information about installing PGMQ, see
[PGMQ Installation](`m:EctoPGMQ#pgmq-installation`).
### Creating a Queue
The most common way to create a queue is in a database migration. We can create
a database migration with the following command:
```bash
mix ecto.gen.migration create_my_queue
```
We can then implement the migration accordingly:
```elixir
defmodule MyApp.Repo.Migrations.CreateMyQueue do
use Ecto.Migration
alias EctoPGMQ.Migrations
def change, do: Migrations.create_queue("my_queue")
end
```
### Sending Messages
Messages can be sent to a queue with the following function:
```elixir
EctoPGMQ.send_messages(MyApp.Repo, "my_queue", [%{"foo" => 1}, %{"bar" => 2}])
```
### Reading Messages
Messages can be read from a queue with the following function:
```elixir
messages = EctoPGMQ.read_messages(MyApp.Repo, "my_queue", 300, 2)
```
Alternatively, messages can also be consumed in a `Broadway` pipeline with the
`EctoPGMQ.Producer` module.
### Dropping a Queue
The most common way to drop a queue is in a database migration. We can create a
database migration with the following command:
```bash
mix ecto.gen.migration drop_my_queue
```
We can then implement the migration accordingly:
```elixir
defmodule MyApp.Repo.Migrations.DropMyQueue do
use Ecto.Migration
alias EctoPGMQ.Migrations
def change, do: Migrations.drop_queue("my_queue")
end
```
