Failed to fetch instance destinations. (Timed out after 10000ms)

Description of erroneous behaviour

We have a Node.js CAP application edom-retailer-core. In MDIClient.js, we are making a request via destination connecting to MdiDestination.

// package.json
"MdiDestination": {
   "kind": "rest",
   "credentials": {
      "destination": "mdi-dest",
      "requestTimeout": 1000000

The API in the destination retrieves 2000 items at a time and if it has more data, it will provide a deltaToken that we use to make the same call but with the deltaToken to retrieve the next 2000 items. We repeat this till all the items are retrieved. Currently our API has 19000+ items.

// MDIClient.js
const MDIDest = await cds.connect.to('MdiDestination');
const logRequest = new cds.Request();
const baseQuery = `GET /log/sap.odm.businesspartner.BusinessPartner`;

let moreData = true;
while (moreData) {
   if (deltaToken !== false) {
     logRequest.query = `${baseQuery}?since=${deltaToken}`;
   }
   const response = await MDIDest.tx(logRequest).run(logRequest.query);

   ...

   if (!response.hasMoreEvents) {
      moreData = false;
   }
}

The request is successful for the first 6-9 iterations but throws an error afterwards:

Error: Timed out after 10000ms
    at buildError (/mnt/c/Users/C5315270/Desktop/projects/edom-retailer-core/node_modules/opossum/lib/circuit.js:710:17)
    at Timeout.<anonymous> (/mnt/c/Users/C5315270/Desktop/projects/edom-retailer-core/node_modules/opossum/lib/circuit.js:511:29)
    at listOnTimeout (internal/timers.js:554:17)
    at processTimers (internal/timers.js:497:7) {
  cause: ErrorWithCause: Failed to fetch instance destinations.
      at new ErrorWithCause (/mnt/c/Users/C5315270/Desktop/projects/edom-retailer-core/node_modules/@sap-cloud-sdk/util/dist/error-with-cause.js:31:16)
      at /mnt/c/Users/C5315270/Desktop/projects/edom-retailer-core/node_modules/@sap-cloud-sdk/core/dist/connectivity/scp-cf/destination/destination-service.js:116:27
      at runNextTicks (internal/process/task_queues.js:62:5)
      at listOnTimeout (internal/timers.js:523:9)
      at processTimers (internal/timers.js:497:7)
      at async Promise.all (index 0)

I attached the console log and console error below. log.txt error.txt

Detailed steps to reproduce

For example (→ replace by appropriate ones for your case):

1. git clone https://github.wdf.sap.corp/c4u/edom-retailer-core.git
2. git checkout feat/25-mdiclient-outbound
3. npm install
4. cds deploy
5. cds run
6. In Postman, make a GET request to http://localhost:4004/api/alpha/mdiclient/MDIClient

Details about your project

edom-retailer	https://github.wdf.sap.corp/c4u/c4u-cn-edom-retailer
CAP Java Runtime	version
OData Version	version
@sap/cds-compiler	2.1.6
@sap/cds-dk	4.0.7

Used Versions:

• node version via node -v: v12.22.1
• npm version via npm -v: 6.14.12
• SAP Cloud SDK version you used as dependency
  • “@sap-cloud-sdk/core”: “^1.41.0”,

[LaxOn]

I’m able to connect to the consumer subaccount by providing a userJwt. Thank you! await cloudSDK.getDestination('mdi-dest',{ useCache: true, isolationStrategy: "Tenant", userJwt:jwt})

[marikaner]

Hey @LaxOn,

btw, you can enable the SDK caching if you transform this line: const dest = await cloudSDK.getDestination('mdi-dest'); to this: const dest = await cloudSDK.getDestination('mdi-dest', { useCache: true });