hazelcast-api

Microservice that exposes an API to manage information in Hazelcast Maps

Features

• Write information in a Hazelcast map
• Read information from a Hazelcast map based on a key

Change Log

See CHANGELOG.md

Configuration

Property	Default value	Description
MICRONAUT_SERVER_PORT	6969	The port on the API is listening
MICRONAUT_SERVER_MAX_REQUEST_SIZE	1024	Max size, in bytes, allowed for an incoming request
HAZELCAST_NETWORK_ADDRESSES	localhost:5701	The DNS and port of the Hazelcast cluster
HAZELCAST_CLIENT_NAME	hazelcastApi	The name representing this microservice the list of clients from Hazelcast connections
HAZELCAST_CLIENT_CLUSTERNAME	dev	The name of the Hazelcast cluster to connect
MICRONAUT_METRICS_ENABLED	true	Enable or disable the Micronaut metrics endpoint

API Endpoints

Endpoint	Method	Produces	Consumes	Body	Description
/v1/map	PUT	application/json	application/json	{"key":"foo", "value":"myvalue", "map-name":"mymap"}	Write a key/value on a specific Hazelcast Map
/v1/map	POST	application/json	application/json	{"key":"foo", "map-name":"mymap"}	Get the value from a key on a specific Hazelcast Map

Examples

Write simple key/value in Map named "mymap2"

curl -X PUT http://localhost:6969/v1/map --header "Content-Type: application/json" -d '{"key":"foo","value":"myvalue2", "map-name":"mymap2"}'

Write a complex key/value in Map named "mymap2"

curl -X PUT http://localhost:6969/v1/map --header "Content-Type: application/json" -d '{"key":"foo","value":"{\"internal_key\": \"internal_value\"}", "map-name":"mymap2"}'

Get a value from a key in Map named "mymap2"

curl -X POST http://localhost:6969/v1/map --header "Content-Type: application/json" -d '{"key":"complexkey", "map-name": "mymap2"}'

Docker

Docker image is available on marcosflobo/hazelcast-api

Run simple hazelcast-api container

docker run -it --rm --name my-hazelcast-api -p 6969:6969 marcosflobo/hazelcast-api:1.0.0

Run hazelcast-api container with concrete configuration for Hazelcast cluster

docker run -it --rm --name my-hazelcast-api -p 6969:6969 --env HAZELCAST_NETWORK_ADDRESSES=hazelcast:5701 --env HAZELCAST_CLIENT_NAME=hazelcast-api-docker --env HAZELCAST_CLIENT_CLUSTERNAME=dev --env MICRONAUT_SERVER_PORT=6969 marcosflobo/hazelcast-api:1.0.0 

Development

During development, it's very important test and test fast, not only the application but also how it will work when it's deployed in production. For that, it's important to test via Docker container and, for doing so, we can use a docker-compose file.

The docker-compose.yml file will run:

• Container with the last assembled version of this hazelcast-api app
• Container with Prometheus service, to scrape the metrics exposed by the app
• Container with Grafana service, to visualize the metrics scraped by Prometheus from the app

Run docker-compose

$ ./gradlew clean assemble && docker-compose up --build

• Prometheus is available on http://localhost:9090. Perform some tests on the app API (see chapter above) and wait 30s to query for some metric such as http_server_requests_seconds_count
• Grafana is available on http://localhost:3000
• Hazelcast server is deployed on port 5701
• Hazelcast Management Center is available on http://localhost:8080
• And the hazelcast-api microservice is available on http://localhost:6969

To stop the docker-compose, just type Ctrl+c. To remove the containers created, run docker-compose down.

Metrics

Endpoint	Description
/metrics	Metrics information in JSON format
/prometheus	Metrics information in Prometheus format
/health	Status health of the service in JSON format

Micronaut

• Version 2.1.2. More info at Micronaut 2.1.2
• Official documentation

Feature cache-hazelcast documentation

• Micronaut Hazelcast Cache documentation
• https://hazelcast.org/

Feature management documentation

• Micronaut Micronaut Management documentation

Feature http-client documentation

• Micronaut Micronaut HTTP Client documentation