Add migration plugin-name to hdiconfig

[Nils-Schiwek]

add plugin-name to .hdiconfig for migration

Without this, the migration will not work and deployment will show the following error:
Error: "src/.hdiconfig": Configuration does not define a build plugin for file suffix "hdbmigrationtable"

For me it was hard to find this information and I think it is missing in the documentation.

[renejeglinsky]

Thanks @Nils-Schiwek for opening this PR. I assigned a reviewer and will keep you posted.

[LotharBender]

@Nils-Schiwek - just found out that cds build is adding the required .hdbmigrationtable plugin entry to the wrong .hdiconfig file. Instead of adding the entry to the .hdiconfig file generated in the db/src/gen folder, the entry must be added to the .hdiconfig file located at db/src.
On the other hand, the existing one should already contain the .hdbmigrationtable entry - do you have an idea why this isn't the case?

Note: cds add hana --for production will create a .hdiconfig file in the db/src folder for you containing all known plugin entries.

@renejeglinsky - I think we should mention this command instead of describing how to manually add this entry to the .hdiconfig file or even better a combination of both.

[renejeglinsky]

Thanks @LotharBender ! In this guide we already mention cds add hana: https://cap.cloud.sap/docs/guides/databases-hana#configure-hana

Should we add a hint at the Schema Evolution?

[LotharBender]

Thanks @LotharBender ! In this guide we already mention cds add hana: https://cap.cloud.sap/docs/guides/databases-hana#configure-hana

Should we add a hint at the Schema Evolution?

@renejeglinsky - I think this would be a good idea. To be honest, I was struggling, why Capire suggests to add hana for the [hybrid] profile instead of the [production] profile - this might totally confuse users, at least myself ;-)

[Nils-Schiwek]

On the other hand, the existing one should already contain the .hdbmigrationtable entry - do you have an idea why this isn't the case?

In our project, we did not yet have a migration, also no @cds.persistence.journal. It was a bit fiddly to build it in at this stage of the project. We are still on v7.9.5 so, that might also have some influence. I was impended by error messages on jenkins as my build was failing due to missing .hdiconfig entry for migration and it was hard to find that information. So I would like to improve doc with the information to keep in mind, that the .hdiconfig needs that information to run migrations.

[renejeglinsky]

In our project, we did not yet have a migration, also no @cds.persistence.journal. It was a bit fiddly to build it in at this stage of the project. We are still on v7.9.5 so, that might also have some influence. I was impended by error messages on jenkins as my build was failing due to missing .hdiconfig entry for migration and it was hard to find that information. So I would like to improve doc with the information to keep in mind, that the .hdiconfig needs that information to run migrations.

Maybe we could add that as troubleshooting information in our troubleshooting section. Could you provide an error message we could attach this information to?

[Nils-Schiwek]

In our project, we did not yet have a migration, also no @cds.persistence.journal. It was a bit fiddly to build it in at this stage of the project. We are still on v7.9.5 so, that might also have some influence. I was impended by error messages on jenkins as my build was failing due to missing .hdiconfig entry for migration and it was hard to find that information. So I would like to improve doc with the information to keep in mind, that the .hdiconfig needs that information to run migrations.

Maybe we could add that as troubleshooting information in our troubleshooting section. Could you provide an error message we could attach this information to?

Yes, the logs from btp look like this:

Error: "src/secretEntity.hdbmigrationtable": could not create a compile unit for the file [8211714] (STDERR, APP/TASK/deploy)#

Error: "src/.hdiconfig": Configuration does not define a build plugin for file suffix "hdbmigrationtable" [8210015] (STDERR, APP/TASK/deploy)#

Error: Adding "src/secretEntity.hdbmigrationtable" for deploy... failed [8211700] (STDERR, APP/TASK/deploy)#

[renejeglinsky]

Hi @Nils-Schiwek ,
I'm still struggling to understand what happened. Have you ever executed cds add hana in your project?
I mean even if my project is new, if I add hana, then I get an db/src/.hdiconfig file with hdbmigrationtable in it. And I think this has also been the case for cds7. So does it really play a role that your project hasn't had a migration yet?
To understand it helps to write a proper troubleshooting information, so thanks for taking the time to engage with us.
Best,
René