Gain insights into building scalable backend applications with Elixir, OTP, and Phoenix. Learn about persistent connections via Phoenix Channels, and explore distinct, decoupled application layers.

Functional Web Development with  Elixir, OTP and Phoenix by The Pragmatic Programmer_ .png

elixir_islands_test.tar.gz

elixir-app

pheonix-app

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island-interface

phoenix-app-compiled

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phoenix-app-form

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Elixir and OTP provide exceptional tools to build rock-solid backend applications that scale. In this course, you’ll build a web application in a radically different way, with a backend that holds application state. You’ll use persistent Phoenix Channel connections instead of HTTP’s request-response, and create the full application in distinct, decoupled layers.

In Part 1, you’ll start by building the business logic as a separate application, without Phoenix. You’ll model the application domain with Elixir functions and simple data structures.

In Part 2, you’ll add in the GenServer Behaviour to make managing in-memory state a breeze. 

In Part 3, you’ll build a web interface with Phoenix where you’ll use Phoenix Channels to establish persistent connections between the stateful server and a stateful front-end client.

Needless to say, you’re going to love this way of building web apps!

Functional Web Development with Elixir, OTP and Phoenix

Development, testing, and deployment becomes easy


A focused service is easier to code and maintain

Implementation can be changed when needed without affecting the rest of the application

Each service can be deployed as per its own resource requirements

Which of the following is NOT an advantage of microservices?

Which of the following is NOT an advantage of microservices?

Elixir GenServer Behaviour provides isolation from the rest of the application.

Elixir GenServer Behaviour provides isolation from the rest of the application.

Testing applications that use GenServer requires writing mock code.

Testing applications that use GenServer requires writing mock code.

Using GenServer makes application deployment complex.

Using GenServer makes application deployment complex.

Applications using GenServer require writing lots of plumbing code to implement fault tolerance.

Applications using GenServer require writing lots of plumbing code to implement fault tolerance.

Which of the following statements includes GenServer in our application?

Which of the following statements includes GenServer in our application?

In a GenServer implementation, which of the following actually returns the response to the calling party?

In a GenServer implementation, which of the following actually returns the response to the calling party?

Which of the following is triggered by a call to `GenServer.call/3`?

Which of the following is triggered by a call to <code>GenServer.call/3</code>?

The `handle_call` callback accepts messages sent directly from other processes?

The <code>handle_call</code> callback accepts messages sent directly from other processes?

In `handle_call(:demo_call, _from, state)`, which argument represents the calling process ID?

In <code>handle_call(:demo_call, _from, state)</code>, which argument represents the calling process ID?

```elixir
def handle_cast( {:my_cast, new_state}, state ) do {:ok} end
```

```elixir
def handle_cast( {:my_cast, new_state}, state ) do {:ok, Map.put(new_state)} end

```

```elixir
def handle_cast( {:my_cast, new_state}, state ) do {:ok, Map.put(state, :test, new_state)} end
```

```elixir
def handle_cast( {:my_cast, new_state}, state ) do {:noreply, Map.put(state, :test, new_state)} end
```

Which of the following is a correct cast implementation?

Which of the following is a correct cast implementation?

Let's test our understanding of the concepts covered so far.

Introduction

Mapping Our Route

Model Data and Behavior

Working of State Machines

Add OTP for Concurrency and Fault Tolerance

Process Supervision for Recovery

Generate a New Web Interface with Phoenix

Create Persistent Connections with Phoenix Channels

Appendix

Quiz