Building and Testing

Now that we have the code, we can test the handler:

Go

Install dependencies:

cd go-services
go mod tidy

Build and run the service:

go run ./cmd/counting-backend

Python

Install dependencies:

cd py-services
. ./venv/bin/activate

Run the service:

python3 -m counting_backend

ExpressJS

Install dependencies:

cd js-services/counting-backend
yarn install

Run the service:

yarn dev

If everything is ok you will see service logs:

{"level":"info","@timestamp":"2022-11-13T01:09:13.220317049Z","caller":"app/mify_app.go:72","msg":"Starting...","service_name":"counting-backend","hostname":"your-hostname"}
{"level":"info","@timestamp":"2022-11-13T01:09:13.220364807Z","caller":"app/server.go:37","msg":"starting api server","service_name":"counting-backend","hostname":"your-hostname","endpoint":":33767"}
{"level":"info","@timestamp":"2022-11-13T01:09:13.220425122Z","caller":"app/server.go:37","msg":"starting maintenance server","service_name":"counting-backend","hostname":"your-hostname","endpoint":":39275"}

You can get the port number from starting api server log message, we have 33767 in this example. Use curl or Postman to test your handler:

$ curl 'http://localhost:33767/counter/next'
{"number":0}
$ curl 'http://localhost:33767/counter/next'
{"number":1}

It works!