Cross-MTA Dependency & Destinations

[Steven_UM]

Hi,

I have 2 MTA applications ( in the same org and space ) - one hosting a number of API/ODATA services and another hosting a number of UI5 apps.

Within the UI5 apps I want to define model destinations which reference the API services from the other MTA.

Hence I followed the principle of 'Cross-MTA Dependency' using 'Resource Type “mta-provided”' as explained in the SAP help.

Now in essence this works fine but I am having an issue to pass along the 'url' of the service into the destination.

As per normal destination definition - a url needs to be provided:

So I am guessing that the URL parameter is not 'transferred' between the MTA's as I am getting the error during deployment:

Failed to resolve reference for provided property: 22058223-a79f-45aa-8407-5304bfeb2989-ta8xo1ynf0zp1qba-<xxxx>#services-api#url

If I include the API services within the same MTA then this works fine.

If I 'hard-code' the urls in the consumer mta.yaml then my applications work fine as well.

I have the following definitions in the mta.yaml files:

Provider

modules:
  - name: bc-services-core-api
    type: nodejs
    path: services_api
    provides:
      - name: bc-services-api
        public: true
        properties:
          url: '${default-url}'

Consumer

modules:
  - name: app
    type: html5
    path: app
    requires:
      - name: bc-services-api
        group: destinations
        properties:
          name: services-api
          url: '~{url}'
          forwardAuthToken: true

resources:
  - name: bc-services-api
    type: mta-provided
    parameters:
      mta-id: BC_<XXXX>
      mta-provides-dependency: bc-services-api
      mta-version: '>=0.0.1'

In the SAP help there is small topic about properties which talks about 'cross-reference' of properties and putting a 'requires' under the resources ... but whatever I try I am not able to save the MTA.YAML file then ...

Anyone any suggestions on how to resolve this ? Or am I missing or declared something wrong in the yaml file ?

Also note I am trying this currently out on an HANA Express SPS3 system ( latest patches ) but this needs to run in the cloudfoundry platform eventually ( hopefully there are no differences ).

Thanks,

Steven

[former_member459737]

Hi Steven,

I hope you coped with the XSA as well.
If you have other issues related to MTA deployment, please tell.

Best Regards,
Boyan

[abdel_dadouche]

Thanks for sharing this question, it helped me a lot to find that it was possible. I used it in HANA 1.0 SPS12 with XSA!

[former_member621818]

Hi abdelhalim.dadouche,

Could you please let me know how you integrate with UI5 with the APIs?

Do you set the route in xs-app.json?

Regards,

Tri

[abdel_dadouche]

Hi trimle ,

Yes exactly that, I used the xs-app.json and implemented pattern that would match my external url.

My use case was fairly simple: I need to "host" the SAPUI5 libraries locally on a HANA 1.0 SPS 12 instance while using developing with XSA with the constraint that the server and client have no internet access.

[Dimitar]

Hi Sven,

Your code snippets seem to be properly modeled for the task. Have you double-checked if the 'mta-provided' parameter values are correct? This can be easily done, as at least on cf, when deploying the provider MTA in the progress messages similar rows are printed:

> Publishing publicly provided dependency "<mta-id>:<dependency name>"...

The <mta-id> value and <dependency name> value should be used for the mta-id and mta-provides-dependency parameters of the mta-provided resource.

By the way, there is another way to consume such cross-mta provided configurations - via a 'configuration' resource, which has certain benefits over 'mta-provided'. Below should be a working modelling for your case. Once you get this tested, remember to add additional filters to the configuration resources (e.g. org/space of dependency origin) to prevent side effects in production - e.g. of deployments of other mtas in different spaces .

resources:
- name: bc-services-api
  type: configuration
  parameters:
    provider-nid: mta
    provider-id: <your-mta-ID>:bc-services-api
modules:
  - name: app
    ...
    requires:
      - name: bc-services-api
        properties:
          url: '~{url}'

Please reply if the resolution is still failing.

Dimitar

[Steven_UM]

Thanks Dimitar ... works like a charm - well at least in the cloud.

Didn't try it yet on HANA XSA - what I did notice there though is that by doing 'xs mtas' that my MTA was not listed there .... bit weird but maybe as I directly choose the 'run option' it is not actually registering as being 'deployed' ?