Hybrid method 1: Automatic Wasm pull

Diagram: Example of Client communicating via hybrid runner with automatic wasm retrieval

To configure nodegen-server for automatic Wasm module retrieval, you need to set the following environment variables.

Environment variable	Description
USE_SAAS	false This must always be set as false. The setting of true is for Coherent deployments on our SaaS environments. The default value is true.
SERVICE_ENDPOINTS__EXCELENGINE_SERVICEURL	The base URL of your Spark SaaS account https://excel.{environment}.coherent.global.
SAAS_SERVICE_AUTH_TYPE	syntheticKey or OAuth2
SAAS_SERVICE_SYNTHETIC_KEY	If SAAS_SERVICE_AUTH_TYPE is syntheticKey then this value has to be configured. API key created from Authorization - API keys. The API key groups must contain User groups that are also assigned to Permissions - Features permissions Spark.GetNodegenZip.json and Spark.Resolver.json or assigned to Spark.AllEncompassingProxy.json.
SAAS_SERVICE_OAUTH_ISSUER_BASE_URL	If SAAS_SERVICE_AUTH_TYPE is OAuth2 then this value has to be configured. https://keycloak.{environment}.coherent.global
SAAS_SERVICE_OAUTH_CLIENT_ID	If SAAS_SERVICE_AUTH_TYPE is OAuth2 then this value has to be configured. This can be setup with Client Credentials.
SAAS_SERVICE_OAUTH_CLIENT_SECRET	If SAAS_SERVICE_AUTH_TYPE is OAuth2 then this value has to be configured. This can be setup with Client Credentials.
CLEANUP_INTERVAL	The interval in milliseconds before cleaning up any downloaded Wasm modules. The default value is 43200000 milliseconds (12 hours).

1. Ensure that the Docker engine/daemon is up and running.

2. pull the nodegen-server Docker image using the following command:

   docker pull ghcr.io/coherent-partners/nodegen-server

3. run the service and create a container called wasm-server.

   1. Define the parameters that will be used for authorization to the Spark servers. In this example we are using a syntheticKey for authorization.

   docker run --name wasm-server -p 3000:3000 -d -it \
     -e USE_SAAS=false \
     -e SAAS_SERVICE_AUTH_TYPE=syntheticKey \
     -e SERVICE_ENDPOINTS__EXCELENGINE_SERVICEURL=https://excel.myenvironment.coherent.global \
     -e SAAS_SERVICE_SYNTHETIC_KEY=22f68e51-b04b-4a46-b0aa-a629a8a3fca8 \
     -e CLEANUP_INTERVAL=43200000 \
     ghcr.io/coherent-partners/nodegen-server

4. Test the service using the healthcheck endpoint. You should receive the message {"msg":"ok"}.

   curl 'http://localhost:3000/healthcheck'

5. Execute a request similar to that in the API Tester.

   • Note the change in the URI to localhost:3000 and make sure to update mytenant in the URI to your tenant name.

   • See Execute API (v3) for more information on the request_data and request_meta structure and options.

     • Also see the Hybrid Runner API reference for alternative endpoints available from the runner.

   curl --location --request POST 'http://localhost:3000/mytenant/api/v3/execute' \
   --header 'Content-Type: application/json' \
   --data '{
       "request_data": {
           "inputs": { "A": 1 , "B": 2 }
       },
       "request_meta": {
           "version_id": "c16d9b89-92c4-430f-a30e-9b04805fcb78",
           "call_purpose": "Online",
           "source_system": "Hybrid Runner"
       }
   }'

6. nodegen-server will first perform a lookup and verify whether the Spark service was already downloaded and cached locally.

   • If the service is not found locally, nodegen-server will use the provided Spark credentials to download the Wasm module from the SaaS platform and cache it until the CLEANUP_INTERVAL is reached.

   • If the service is found locally, nodegen-server will execute the Wasm module by loading it into memory, running the encapsulated logic, and returning the results back to the end-user.

7. It is good practice to stop and remove containers when you are finished.

   # stop the container
   docker stop wasm-server
   
   # remove the container
   docker rm wasm-server