quickstarts/service_invocation/go/http

Service Invocation

In this quickstart, you'll create a checkout service and an order-processor service to demonstrate how to use the service invocation API. The checkout service uses Dapr's HTTP proxying capability to invoke a method on the order processing service.

Check out the documentation about service invocation for more details.

This quickstart includes one checkout service: Go client service checkout

And one order processor service: Go order-processor service order-processor

Run all apps with multi-app run template file:

This section shows how to run both applications at once using multi-app run template files with dapr run -f .. This enables to you test the interactions between multiple applications.

1. Open a new terminal window and run the multi app run template:

dapr run -f .

The terminal console output should look similar to this:

== APP - checkout-http == Published data: {"orderId":1}
== APP - order-processor == Subscriber received: {"orderId":1}
== APP - checkout-http == Published data: {"orderId":2}
== APP - order-processor == Subscriber received: {"orderId":2}
== APP - checkout-http == Published data: {"orderId":3}
== APP - order-processor == Subscriber received: {"orderId":3}
== APP - checkout-http == Published data: {"orderId":4}
== APP - order-processor == Subscriber received: {"orderId":4}
== APP - checkout-http == Published data: {"orderId":5}
== APP - order-processor == Subscriber received: {"orderId":5}
== APP - checkout-http == Published data: {"orderId":6}
== APP - order-processor == Subscriber received: {"orderId":6}
== APP - checkout-http == Published data: {"orderId":7}
== APP - order-processor == Subscriber received: {"orderId":7}
== APP - checkout-http == Published data: {"orderId":8}
== APP - order-processor == Subscriber received: {"orderId":8}
== APP - checkout-http == Published data: {"orderId":9}
== APP - order-processor == Subscriber received: {"orderId":9}
== APP - checkout-http == Published data: {"orderId":10}
== APP - order-processor == Subscriber received: {"orderId":10}

3. Stop and clean up application processes

dapr stop -f .

Run a single app at a time with Dapr (Optional)

An alternative to running all or multiple applications at once is to run single apps one-at-a-time using multiple dapr run .. -- go run . commands. This next section covers how to do this.

Run Go order-processor with Dapr

1. Run the order-processor app with Dapr in the order-processor folder:

cd ./order-processor
dapr run \
  --app-port 6006 \
  --app-id order-processor \
  --app-protocol http \
  --dapr-http-port 3501 \
  -- go run .

Run Go checkout with Dapr

1. Open a new terminal window and navigate to checkout directory, then run the Go checkout app with Dapr:

cd ./checkout
dapr run \
  --app-id checkout \
  --dapr-http-port 3500 \
  -- go run .

Stop the apps and clean up

dapr stop --app-id checkout
dapr stop --app-id order-processor