Quickstart

Get Mercury Composable running with a working example app in under 5 minutes.

Prerequisites

  • Java 21 or higher — verify with java --version
  • Maven 3.9.7 or higher — verify with mvn --version
  • Git — verify with git --version

1. Clone and build

git clone https://github.com/Accenture/mercury-composable.git
cd mercury-composable
mvn clean install

The first build downloads all dependencies and may take a few minutes.

2. Run the example app

cd examples/composable-example
java -jar target/composable-example-4.3.69.jar

Look for these lines in the startup output to confirm the app is running:

CompileFlows - Loaded create-profile
CompileFlows - Loaded delete-profile
CompileFlows - Loaded get-profile
CompileFlows - Event scripts deployed: 3
AppStarter - Reactive HTTP server running on port-8100

3. Try it out

The example app is a simple profile management API. Run these commands in a new terminal while the app is running.

Create a profile

curl -s -X POST http://127.0.0.1:8100/api/profile \
  -H "Content-Type: application/json" \
  -H "Accept: application/json" \
  -d '{"id": 100, "name": "Hello World", "address": "100 World Blvd", "telephone": "123-456-7890"}' | jq .

jq is optional — omit | jq . if you don't have it installed.

You should see a 201 Created response:

{
  "profile": {
    "address": "***",
    "name": "Hello World",
    "telephone": "***",
    "id": 100
  },
  "type": "CREATE",
  "secure": ["address", "telephone"]
}

Retrieve the profile

curl -s http://127.0.0.1:8100/api/profile/100 | jq .

You should see a 200 OK response:

{
  "address": "100 World Blvd",
  "name": "Hello World",
  "telephone": "123-456-7890",
  "id": 100
}

Delete the profile

curl -s -X DELETE http://127.0.0.1:8100/api/profile/100 | jq .

You should see a 200 OK response:

{
  "id": 100,
  "deleted": true
}

What just happened?

The app loaded three event flow configurations (create-profile, delete-profile, get-profile) from the flows/ directory. Each HTTP request was routed through its matching event flow, which orchestrated one or more self-contained Java functions. Notice that address and telephone appear as *** in the create response — the flow runs them through an encryption step before storing the profile. The GET request decrypts them back. Every function is stateless; the flow's state machine tracks intermediate results between steps. Explore the flow files at examples/composable-example/src/main/resources/flows/.

Next steps