Learn to implement microservices across a range of common tech stacks.

Scalability & System Design for Developers

In this module, we’ll look at some fundamental concepts for implementing microservices. Within each concept, learn about the different technologies used to implement it. The technologies include front-end integration with Edge Side Includes (ESI), asynchronous microservices with Kafka and REST feeds, synchronous microservices with the Netflix stack, and Consul, Docker, Kubernetes, Cloud Foundry. Each technology is described and then demonstrated with real code.

Microservice Architecture: Practical Implementation

## Introduction

Zuul is the **routing solution** that is part of the Netflix stack. 

Zuul is responsible for forwarding external calls to the correct microservice.


## Zuul vs. reverse proxy

The routing could also be provided by a Reverse Proxy. 

> A **Reverse Proxy** is a web server that is configured to forward incoming calls to other servers.



# Introduction

Zuul is the **routing solution** that is part of the Netflix stack. 

Zuul is responsible for forwarding external calls to the correct microservice.


# Zuul vs. reverse proxy

The routing could also be provided by a Reverse Proxy. 

> A **Reverse Proxy** is a web server that is configured to forward incoming calls to other servers.



Zuul has a feature that a reverse proxy is lacking, **dynamic
filters**:
-  Depending on the properties of the HTTP request or external
configurations, Zuul can **forward certain calls to specific servers** or
execute logic for logging, for example.
- A developer can write **custom
code** for the routing decision.
-  The code can even be dynamically
loaded as Groovy code at runtime.

In this way, Zuul ensures **maximum
flexibility**.

- Zuul filters can also be used to implement central functionalities
such as **logging of all requests**.
- A Zuul filter can implement the
login, send information about the current user with the HTTP requests,
and thereby implement **authentication**. 

Zuul can **take over typical
functionalities of an API gateway** (see
[Benefits & Challenges](https://www.educative.io/courses/microservice-architecture-practical-implementation/benefits-challenges)).


In this lesson, we'll discuss routing with Zuul.

Self-contained Systems

Concept: Frontend Integration

Recipe: Links and Client-side Integration

Recipe: Server-side Integration using Edge Side Includes (ESI)

Concept: Asynchronous Microservices

Recipe: Messaging and Kafka

Recipe: Asynchronous Communication with Atom and REST

Concept: Synchronous Microservices

Recipe: REST with the Netflix Stack

Recipe: REST with Consul and Apache httpd

Concept: Microservices Platforms

Recipe: Docker Containers with Kubernetes

Recipe: PaaS with Cloud Foundry

Router: Zuul

Introduction #

Zuul vs. reverse proxy #