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Tag: multitenancy

CAP

[CAP] Get subdomain in a multitenant scenario

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Until recently, I was always decoded the JWT to get the subdomain of a subscribed tenant like this:

const jwt = retrieveJwt(req)
const subdomain = decodeJwt(jwt).ext_attr.zdn

I now noticed that you can also use the original request object and the getSubdomain function of the authInfo object. It’s provided by @sap/xssec and is only available when using XSUAA, means not with mocked authentication. This way you can get the subdomain in a single line:

const subdomain = req.http.req.authInfo.getSubdomain()

And there are some more helpful functions, that are documented here:

CAP

[CAP] Dynamically set destination in package.json for an external connection

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  "cds": {
    "requires": {
      "sfsf": {
        "kind": "odata-v2",
        "credentials": {
          "destination": "<set during runtime>",
          "path": "/odata/v2",
          "requestTimeout": 18000000
        }
      }
    }
  },

  /*
   * Handover query to some external SF OData Service to fecth the requested data
   */  
  srv.on("READ", Whatever, async req => {

        const sf_api_def = cds.env.requires['sfsf'] //defined in package.json

        sf_api_def.credentials.destination = "myDestinationName" //set your Destination name, could come from a customizing table

        const sfsfSrv = await cds.connect.to(sf_api_def)

        return await sfsfSrv.run(req.query)
    })

CAP

[CAP] Use Destinations from Subscriber Account

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While working on this topic, there are currently two chapters in the CAP docs regarding this topic:

And some SCN posts: here, here and here

But all this didn’t help me to complete the task. Got the solution which finally worked for me from this SAP Sample Susaas (two snippets: here and here).

server.js

const cds = require("@sap/cds")

cds.on('served', async () => {
    const { 'cds.xt.SaasProvisioningService': provisioning } = cds.services
    // Add provisioning logic only if multitenancy is there..
    if (provisioning) {
        let tenantProvisioning = require('./provisioning')
        provisioning.prepend(tenantProvisioning)
    } else {
        console.log(">>> There is no service, therefore does not serve multitenancy!")
    }
})

module.exports = cds.server

provisioning.js

const xsenv = require('@sap/xsenv')
xsenv.loadEnv()

module.exports = (service) => {

    service.on('dependencies', async (req, next) => {
        let dependencies = await next()
        const services = xsenv.getServices({
            registry: { tag: 'SaaS' },
            destination: { tag: 'destination' }
        })
        dependencies.push({ xsappname: services.destination.xsappname }) //adds the subscriber destination as dependency
        console.log(">>> SaaS Dependencies:", JSON.stringify(dependencies))
        return dependencies
    })

}

It injects the destination dependency by manually reading it using xsenv package and returning it in a dependencies callback handler.