slides

Prerequisite

have access to a npm repo to deploy artifacts, for example by running Nexus locally (assume that latest version has been installed and configured at $HOME/app/nexus-3.25.0-03 )

cd $HOME/app/nexus-3.25.0-03/bin
./nexus start

maven's settings.xml and ~/.npmrc should be configured to allow uploading artifacts to the repositories and 'npms' repository created in nexus (for npm packages)

k8s up and running, via minikube or Docker Desktop

Docker daemon available for image creation ( default with Docker Desktop, )

Generate Client and Server sides from Interface Definition

Well Defined Contract between server and client. It is quite tolerant of changes as long as rules of evolution are followed
https://blog.envoyproxy.io/evolving-a-protocol-buffer-canonical-api-e1b2c2ca0dec

Note: every change should update version number, no snapshots! Note: to avoid version number change we can remove artifacts from repo: http://localhost:8081/#browse/browse

cd interface
./build-stubs.sh

that generates server side implementation stubs and client, plus versioned documentation in html and markdown formats. HTML documentation is publisheable and markdown is convenient for embedding into npm module

Run Postgres DB

Easy to run in K8s (for example local docker or other mini k8s)

cd k8s
./render-postgres-chart.sh
kubectl apply -f target/pg-k8s-descriptor.yaml

that gives us Postgres running in k8s and exposed on port 30303. Let us now create a database there and call it 'geography' ( or any other name but more adjustments will be necessary)

Create Database and DB schema

 cd geography-service
 ./create-db.sh  
 ./run-db-migration.sh 

Lets (re)-Generate DAO layer

 cd geography-service
 ./run-dao-gen.sh

Run Service

cd geography-service    
source set-db-env.sh    
mvn  spring-boot:run

Run Proxy

compile or download Envoy or grpcwebproxy binaries for your machine https://www.envoyproxy.io/ or https://github.com/improbable-eng/grpc-web/tree/master/go/grpcwebproxy

then run ./run-grpcweb-proxy.sh or ./run-envoy-proxy-grpc-auth.sh in proxy subdirectory

cd proxy
./run-envoy-proxy-grpc-auth.sh

Run Clients

WEB SPA

it is a standard Angular 8 application

Before we run client we need to set up secrets, if you have given access to the secrets you can simply run

git-secret reveal

if not, then please copy geography-client/src/environments/environment-template.ts into geography-client/src/environments/environmen.ts and place there a valid google API key that allows working with Maps API

cd geography-client
npm install
ng s

now we can access application at http://localhost:4200 log in with Auth0 and start managing areas: lets create one or two

Application

after login we can copy Bearer token on browser's network tab and paste it into file
geography-grpc-client/config/jwt.txt

cd geography-grpc-client
mvn test