Question Re: Programmatically trigger draft events in CAP in Technology Q&A

Programmatically trigger draft events in CAP

Steven-Mason — Wed, 23 Oct 2024 18:31:29 GMT

We have a use case in CAP where we are programmatically triggering draft events (create, prepare, activate, discard). We were able to do this for the "create" draft event via the following code:

const { draftEntity } = service.entities const payload = {} await service.send({query:INSERT.into(draftEntity).entries(payload), event: 'NEW'})

Unfortunately we have not been able to figure out how to trigger the prepare, activate, and discard events. We have tried the following and various iterations with no success:

const { draftEntity } = service.entities //draftEntityID is the passed in ID for the draft entity we want to activate await service.send({ event: 'draftActivate', entity: draftEntity, data: {}, params: [{ID: draftEntityID, IsActiveEntity: false}]})

Being able to do this is very important to our overall design. Any suggestions on how to accomplish this would be greatly appreciated!

For reference, here are the CAP relevant versions we are at while trying this:

-js/asyncapi: 1.0.2 @cap-js/db-service: 1.14.0 @cap-js/hana: 1.3.2 @cap-js/openapi: 1.0.6 @sap/cds: 8.3.1 @sap/cds-compiler: 5.3.2 @sap/cds-dk: 8.3.0 @sap/cds-dk (global): 8.2.2 @sap/cds-fiori: 1.2.3 @sap/cds-foss: 5.0.0 @sap/cds-mtxs: 2.2.0 @sap/eslint-plugin-cds: 3.1.0 Node.js: v18.20.3

Re: Programmatically trigger draft events in CAP

catano — Tue, 29 Oct 2024 14:04:05 GMT

Hi,

Do you think these events you describe could be replaced by plain CRUD requests?
For example activate with a READ draft and a CREATE non-draft call, or discard with a DELETE draft call?
The reason I ask is because if using a * event listener to see what is running under the hood as a result of draft create, update and create from draft, these are pretty much what is happening.
Is there a reason why you can't use these?

Peter

Re: Programmatically trigger draft events in CAP

catano — Tue, 29 Oct 2024 14:06:49 GMT

I tried to craft a request to call draftPrepare for example - what is called by the framework by default - but I cannot make it work: even if I have the same query, method, params and everything I still cannot pass Symbol(draftParams) = { IsActiveEntity: false } down the stream.

Re: Programmatically trigger draft events in CAP

Steven-Mason — Wed, 30 Oct 2024 20:27:52 GMT

Thanks Peter,

I have tried sending the "standard" events coming through the system based. For example, I have used "SAVE" instead of draftActivate. Example of this being:

const { draftEntity } = service.entities //draftEntityID is the passed in ID for the draft entity we want to activate await service.send({ event: 'SAVE', entity: draftEntity, data: {}, params: [{ID: draftEntityID, IsActiveEntity: false}]})

While the framework does not reject this, it does not successfully trigger the draftActivate behavior observed from calls to the OData service.

Anyone else have any ideas on what I am doing wrong and how I could do this programmatically?

Re: Programmatically trigger draft events in CAP

catano — Thu, 31 Oct 2024 06:04:53 GMT

If creating a non-draft entity instance of the draft, then what I tried to suggest is do the following steps:

Taking the ID of the draft entity:

read draft entity data by ID
create non-draft entity with draft data
update draft data to reflect state after creating non-draft from draft, either delete draft or do any necessary status change of draft

This is just an idea, I don't know if it is feasible or not without knowing the complete scenario of yours.

Re: Programmatically trigger draft events in CAP

catano — Thu, 31 Oct 2024 06:11:51 GMT

I just played around with the stuff, but still have no idea. I could craft the HTTP request to call the draft actions but cannot call them programatically, even when try to fully copy the request made by the framework itself..

http://localhost:4004/odata/v4/service/Entity(ID=c2b16e23-d129-4134-9558-1512c75ceb62,IsActiveEntity=false)/Service.draftPrepare http://localhost:4004/odata/v4/service/Entity(ID=c2b16e23-d129-4134-9558-1512c75ceb62,IsActiveEntity=false)/Service.draftActivate

I would assume that the following should work:

srv.send('GET', `Entity(ID=${id},IsActiveEntity=false)/Service.draftPrepare`);

but I'm a bit confused because I cannot even make it work a basic query like:

srv.send('GET', 'Entity');

I'm still getting error message:

[cds] - Error: The request has no query and cannot be served generically. at module.exports (/Users/petermanuel.catano/projects/sap-btp-cloud-full-stack-challange/node_modules/@sap/cds/libx/_runtime/common/error/index.js:5:48) at ApplicationService.<anonymous> (/Users/petermanuel.catano/projects/sap-btp-cloud-full-stack-challange/node_modules/@sap/cds/libx/_runtime/common/generic/crud.js:17:13) at next (/Users/petermanuel.catano/projects/sap-btp-cloud-full-stack-challange/node_modules/@sap/cds/lib/srv/srv-dispatch.js:69:36) at ApplicationService.handle (/Users/petermanuel.catano/projects/sap-btp-cloud-full-stack-challange/node_modules/@sap/cds/lib/srv/srv-dispatch.js:73:6) at async ApplicationService.handle (/Users/petermanuel.catano/projects/sap-btp-cloud-full-stack-challange/node_modules/@sap/cds/libx/_runtime/common/Service.js:84:16) at async ApplicationService.<anonymous> (/Users/petermanuel.catano/projects/sap-btp-cloud-full-stack-challange/srv/service.js:124:18) at async next (/Users/petermanuel.catano/projects/sap-btp-cloud-full-stack-challange/node_modules/@sap/cds/lib/srv/srv-dispatch.js:69:17) at async ApplicationService.handle (/Users/petermanuel.catano/projects/sap-btp-cloud-full-stack-challange/node_modules/@sap/cds/lib/srv/srv-dispatch.js:67:10) at async ApplicationService.handle (/Users/petermanuel.catano/projects/sap-btp-cloud-full-stack-challange/node_modules/@sap/cds/libx/_runtime/common/Service.js:84:16) {