Getting Started with Hybrid Mode for Java Development

This tutorial will show you how to develop and debug a sample Java application using Okteto Hybrid Mode.

Prerequisites

Install the latest version of the Okteto CLI and configure it to access Okteto. Follow our installation guide if you haven't done it yet.

Step 1: Deploy the Sample App

Get a local version of the Sample App by executing the following commands:

git clone https://github.com/okteto/microservices-demo
cd microservices-demo

Checkout the branch with the Hybrid Mode configuration:

git checkout hybrid

At the root of the directory, you'll find the okteto.yml file. This file describes how to deploy the Sample App.

deploy:
  - helm upgrade --install postgresql postgresql/postgresql-11.6.2.tgz -f postgresql/values.yml
  - helm upgrade --install kafka kafka/kafka-17.1.0.tgz -f kafka/values.yml
  - helm upgrade --install vote vote/chart --set image=${OKTETO_BUILD_VOTE_IMAGE}
  - helm upgrade --install result result/chart --set image=${OKTETO_BUILD_RESULT_IMAGE}
  - helm upgrade --install worker worker/chart --set image=${OKTETO_BUILD_WORKER_IMAGE}

The Sample App consists of the following services:

• A front-end web app in Java which lets you vote between Tacos and Burritos
• A Kafka queue which collects new votes
• A Golang worker which consumes votes from Kafka and stores them in PostgresQL
• A PostgresQL database
• A Node.js webapp which shows the results of the voting in real time

Deploy the Sample App by executing:

okteto deploy

 i  Using cindy @ okteto.example.com as context
 i  Running 'helm upgrade --install postgresql postgresql/postgresql-11.6.2.tgz -f postgresql/values.yml'
...
 i  Running 'helm upgrade --install kafka kafka/kafka-17.1.0.tgz -f kafka/values.yml'
...
 i  Running 'helm upgrade --install vote vote/chart --set image=${OKTETO_BUILD_VOTE_IMAGE}'
...
 i  Running 'helm upgrade --install result result/chart --set image=${OKTETO_BUILD_RESULT_IMAGE}'
...
 i  Running 'helm upgrade --install worker worker/chart --set image=${OKTETO_BUILD_WORKER_IMAGE}'
...
 ✓  Development environment 'microservices-demo' successfully deployed
 i  Endpoints available:
  - https://vote-cindy.okteto.example.dev
  - https://result-cindy.okteto.example.dev

Step 2: Activate your Development Container

The dev section defines how to activate a Development Container for the Sample App:

dev:
  vote:
    mode: hybrid
    command: bash # mvn spring-boot:run
    workdir: vote
    reverse:
      - 8080:8080
    forward:
      9092:kafka:9092

The vote key matches the name of the hello world Deployment. The definition of the rest of fields are:

• mode: to configure Hybrid development mode
• command: the command to start the java service locally
• workdir: the working dir of the command
• reverse: to expose the local port 8080 in the Development Container port 8080 using a reverse tunnel
• forward: to expose the kafka port 9092 on localhost to access kafka fron your local machine

Next, execute the following command to activate your Development Container:

okteto up vote

 i  Using cindy @ okteto.example.com as context
 i  Development environment 'microservices-demo' already deployed.
 ✓  Reverse tunnel configured
    Context:   okteto.example.com
    Namespace: cindy
    Name:      vote
    Forward:   9092 -> kafka:9092
    Reverse:   8080 <- 8080

bash-3.2$

You can run mvn spring-boot:run to start the vote service locally. Your local maven process will be still available from its okteto endpoint because the local port 8080 is accessible via a reverse tunnel to the cluster.

The vote needs to connect to Kafka. You can change the code of the vote service to connect to kafka on localhost, or add the following entries to your /etc/hosts file:

127.0.0.1 kafka
127.0.0.1 kafka-0.kafka-headless.<<your-namespace>>.svc.cluster.local