Building Microservices in Go YouTube

Code repository for my Building Microservices YouTube series https://www.youtube.com/playlist?list=PLmD8u-IFdreyh6EUfevBcbiuCKzFk0EW_

Week by week Building Microservices builds on the previous weeks code teaching you how to build a multi-tier microservice system. The code structure for the course is one of a mono repo. To make it simple to follow along, each episode has its own branch showing progress to date.

Services

Product API ./product-api

RESTful Go based JSON API built using the Gorilla framework. The API allows CRUD based operations on a product list.

Frontend website ./frontend

ReactJS website for presenting the Product API information.

Currency ./currency

gRPC service supporting simple Unaray and Bidirectional streaming methods.

Product Images ./product-images

Go based image service supporting Gzipped content, multi-part forms and a RESTful approach for uploading and downloading images.

Series Content

Over the weeks we will look at the following topics, teaching you everything you need to know regarding building microservices with the go programming language:

• Introduction to microservices
• RESTFul microservices
• gRPC microservices
• Packaging applications with Docker
• Testing microservice
• Continuous Delivery
• Observability
• Using Kubernetes
• Debugging
• Security
• Asynchronous microservices
• Caching
• Microservice reliability using a Service Mesh

Episode 1 - Building a simple microservice

https://youtu.be/VzBGi_n65iU

Branch: episode_1

In this episode I show you how to build the simplest service you can using the standard packages in the Go programming language.

Episode 2 - Building a simple microservice, continued

https://youtu.be/hodOppKJm5Y

Branch: episode_2

In this episode we learn more about the standard library and look at how we can refactor last episodes example into a reusable microservice pattern.

Episode 3 - RESTFul microservices

https://youtu.be/eBeqtmrvVpg

Branch: episode_3

In this episode we start to learn about RESTFul services and reading and writing data using the JSON format.

Episode 4 - RESTful microservices

https://youtu.be/UZbHLVsjpF0

Branch episode_4

We continue to look at how you can implement RESTFul services with the Standard API

Episode 5 - Gorilla toolkit

https://youtu.be/DD3JlT_u0DM

Branch episode_5

In this epsode we refactor our Standard library RESTful service and start to implement the Gorill toolkit for routing.

Episode 6 - JSON Validation

https://youtu.be/gE8_-8KoOLc

Branch episode_6

In this episode we will look at the Go Validator package and how it can be used to validate JSON.

Episode 7 - Documenting APIs with Swagger

https://youtu.be/07XhTqE-j8k

Branch episode_7

This epsiode shows you how you can document the API we have been building over the last couple of weeks. As a bonus we will also look at how we can embed ReDoc to build a nice documentation API direct into our service.

Episode 8 - Auto-generating HTTP client code from Swagger documentation

https://youtu.be/Zn4joNjqBFc

Branch episode_8

In this episode we look at how we can use the Swagger API documentation we created in the last episode and generate a Go client SDK. As it turns out I had a little bug in my code hope you all find the process of debugging this and finding root cause useful too.

Episode 9 - CORS (Cross-Origin Resource Sharing)

https://youtu.be/RlYoy_RiYPw

Branch episode_9

In this episode we are going to take a look at CORS (Cross-Origin Resource Sharing). CORS is a security feature built into web browsers which restricts upstream requests to sites on different domains. We look at a typical example of a React website on one domain calling a back end API, see the impact of CORS and how to solve it.

Episode 10 - Serving and uploading files

https://youtu.be/ctmhYJpGsgU

Branch episode_10

In this episode you will learn how to upload and serve files using the Go standard library.

Episode 11 - Handling multi-part form uploads

https://youtu.be/_7-IhHMptNo

Branch episode_11

In this episode you will learn how to handle multi-part form uploads. Mult-part forms used to be common place as they are the basic way that browsers would upload data to a server. This pattern has fallen out of fashion as most moder data transfer to the server is done using XHR requests. There might still be a case when you need to know this though.

Episode 12 - Using Gzip compression for HTTP responses

https://youtu.be/GtSg1H7SU5Y

Branch episode_12

In this episode we walk through how to wrap a http.ResponseWriter to enable Gzip compression for HTTP responses.

HTTP Headers Accept-Encoding: https://developer.mozilla.org/en-US/d...

HTTP ResponseWriter: https://golang.org/pkg/net/http/#Resp...

Episode 13 - Introduction to gRPC and Protocol Buffers

gRPC is a high performance framework for client server applications. It is designed to be cross platform and is an awesome alternative to RESTful services.

In this episode we take a quick look at gRPC and Protocol Buffers, and how you can use them to build a simple API. This is the first video in a series of content where we dig into gRPC services.

gRPC Framework: https://grpc.io/

Protocol Buffers v3 Language Guide: https://developers.google.com/protocol-buffers/docs/proto3

Protocol Buffers v3 Encoding format: https://developers.google.com/protocol-buffers/docs/encoding

https://youtu.be/pMgty_RYIOc

Branch episode_13

Episode 14 - gRPC Client Connections

In this episode we take a quick look at how you can connect to gRPC services in Go.

Protocol Buffers Enum Specification: https://developers.google.com/protocol-buffers/docs/reference/proto3-spec#enum_definition

gRPC Creating gRPC Clients: https://grpc.io/docs/tutorials/basic/go/#client

https://youtu.be/oTBcd5J0VYU

Branch episode_14

Episode 15 - Refactoring Part 1/3

This video is part 1 of 3 where we start to clean up the code base a little before continuing to develop our gRPC service. Refactoring is a natural part of software development, it is difficult to get things right first time all the time. Rather than spend too much time on the perfect solution I like to go with the flow and clean up at a later date.

As part of our refactoring we look at the encoding/xml and how it is very similar in use to encoding/json.

Encoding/XML: https://golang.org/pkg/encoding/xml/

https://youtu.be/Vl88R9acq-Y

Branch episode_15_1

Episode 15 - Refactoring Part 2/3

In this episode I continue to refactor the code base so far. These videos are really just intended to ensure that you are not completely confused when looking at the source code changes between episode 14 and episode 16.

Source Code: https://github.com/nicholasjackson/building-microservices-youtube/tree/episode_15_2

Encoding/XML: https://golang.org/pkg/encoding/xml/

https://youtu.be/QBl8LZ0Rems

Branch episode_15_2

Episode 15 - Refactoring Part 3/3

In this episode I finalize the refactoring for the code base.

https://youtu.be/ARvOyAsuFog

Branch episode_15_2

Episode 16 - gRPC Bi-directional streaming, part 1/2

In this video we start to look at gRPC bi-directional streaming

gRPC streaming allows you to independently receive streamed messages from the client and send a response to it. This episode looks at the basics of streaming API by adding an update to our currency service.

Server-side streaming: https://grpc.io/docs/languages/go/basics/#server-side-streaming-rpc

Client-side streaming: https://grpc.io/docs/languages/go/basics/#client-side-streaming-rpc

https://youtu.be/4ohwkWVgEZM

Branch episode_16

Episode 17 - gRPC Bi-directional streaming, part 2/2

In this video we continue to look at gRPC bi-directional streaming.

You will see how to take the simple example in the first part and how it can be implemented into the Products API to support independent client and server streams. The simple example allows a client in the Product API to subscribe for currency rate changes in the Currency service. Whenever a rate changes the currency service broadcasts this change to all interested subscribers.

Server-side streaming: https://grpc.io/docs/languages/go/basics/#server-side-streaming-rpc

Client-side streaming: https://grpc.io/docs/languages/go/basics/#client-side-streaming-rpc

https://youtu.be/MT5tXSKa-KY

Branch episode_17