Event Sourcing + CQRS using Go Workshop

BACKGROUND

Imagine that you are working for a large news publisher called FairFlax Media, not to be mistaken with Fairfax Media, inspired by flax flower : )

You are breaking our huge monolith system into micro services and moving everything to Kuberentes... You like domain driven desing and we do not allow more than one app to connect to a database. Each DB can be owned by only one application. As time goes by, you notice that many services need common data. You need to make sure that the data is consistent across all services and the query performance is reasonable.

This is when things get interesting...

PREREQUISITES

This requires Go 1.6 or later
Requires that GOPATH is set
Install dep for managing dependencies - https://github.com/golang/dep#installation

On Mac OSX using brew...
```
$ brew install dep
$ brew upgrade dep
```
On other platforms you can use the install.sh script:
```
$ curl https://raw.githubusercontent.com/golang/dep/master/install.sh | sh
```

Add ensure the PATH contains $GOPATH/bin

$ go help gopath
$ export PATH=$PATH:$GOPATH/bin

QUICK INSTALL (I haven't tried it)

$ go get -u github.com/pavelnikolov/eventsourcing-go/demo-articles
$ go get -u github.com/pavelnikolov/eventsourcing-go/demo-graph
$ go get -u github.com/pavelnikolov/eventsourcing-go/demo-sitemap
$ go get -u github.com/pavelnikolov/eventsourcing-go/demo-rss

CLONE THE REPOSITORUY

Either (I haven't tried it):

$ go get github.com/pavelnikolov/eventsourcing-go/...

Or:

$ mkdir -p $GOPATH/github.com/pavelnikolov
$ cd $GOPATH/github.com/pavelnikolov
$ git clone github.com/pavelnikolov/eventsourcing-go

Then install the dependencies:

$ dep ensure

TRY IT!

Run the articles API
```
$ demo-articles &
```
Run the GraphQL gateway API
```
$ demo-graph
```
Run the RSS generator
```
$ demo-rss
```
Run the Sitemap generator
```
$ demo-sitemap
```

Navigate to the apps in your browser:

GraphiQL UI - http://localhost:4001/
Latest news RSS feed - http://localhost:4002/feed
Latest business news RSS feed - http://localhost:4002/feed/business
Latest political news RSS feed - http://localhost:4002/feed/politics
(Naive and useless) Sitemap - http://localhost:4003/sitemap

OPTIONAL - Rebuilding the generated code

Install protobuf compiler

Install the protoc Go plugin

$ go get -u github.com/golang/protobuf/protoc-gen-go

Rebuild the generated Go code

$ go generate github.com/pavelnikolov/eventsourcing-go/...

Or run protoc command (with the grpc plugin)

$ protoc -I publishing/ publishing/publishing.proto --go_out=plugins=grpc:publishing

OPTIONAL - Rebuild and run the apps

go install ./cmd/demo-articles && demo-articles
go install ./cmd/demo-graph && demo-graph
go install ./cmd/demo-rss && demo-rss
go install ./cmd/demo-sitemap && demo-sitemap

sebcante / eventsourcing-go