sap-cf-mailer VError: No service matches destination - sap-cloud-foundry

Question

I have a SAP CAP Nodejs application and I'm trying to send emails from the CAP application using sap-cf-mailer package.
I've created a destination service in the BTP as mentioned in the sample and when I'm trying to deploy the application to BTP it failed.
When I run the application locally using cds watch, it gives following error
VError: No service matches destination
This is my mta.yaml
## Generated mta.yaml based on template version 0.4.0
## appName = CapTest
## language=nodejs; multitenant=false
## approuter=
_schema-version: '3.1'
ID: CapTest
version: 1.0.0
description: "A simple CAP project."
parameters:
enable-parallel-deployments: true
build-parameters:
before-all:
- builder: custom
commands:
- npm install --production
- npx -p #sap/cds-dk cds build --production
modules:
# --------------------- SERVER MODULE ------------------------
- name: CapTest-srv
# ------------------------------------------------------------
type: nodejs
path: gen/srv
parameters:
buildpack: nodejs_buildpack
requires:
# Resources extracted from CAP configuration
- name: CapTest-db
- name: captest-destination-srv
provides:
- name: srv-api # required by consumers of CAP services (e.g. approuter)
properties:
srv-url: ${default-url}
# -------------------- SIDECAR MODULE ------------------------
- name: CapTest-db-deployer
# ------------------------------------------------------------
type: hdb
path: gen/db
parameters:
buildpack: nodejs_buildpack
requires:
# 'hana' and 'xsuaa' resources extracted from CAP configuration
- name: CapTest-db
resources:
# services extracted from CAP configuration
# 'service-plan' can be configured via 'cds.requires.<name>.vcap.plan'
# ------------------------------------------------------------
- name: CapTest-db
# ------------------------------------------------------------
type: com.sap.xs.hdi-container
parameters:
service: hana # or 'hanatrial' on trial landscapes
service-plan: hdi-shared
properties:
hdi-service-name: ${service-name}
- name: captest-destination-srv
type: org.cloudfoundry.existing-service
This is the js file of the CDS service
const cds = require('#sap/cds')
const SapCfMailer = require('sap-cf-mailer').default;
const transporter = new SapCfMailer("MAILTRAP");
module.exports = cds.service.impl(function () {
this.on('sendmail', sendmail);
});
async function sendmail(req) {
try {
const result = await transporter.sendMail({
to: 'someoneimportant#sap.com',
subject: `This is the mail subject`,
text: `body of the email`
});
return JSON.stringify(result);
}
catch{
}
};
I'm following below samples for this
Send an email from a nodejs app
Integrate email to CAP application

Answer 1

Did you create your default-.. json files? They are required to connect to remote services on your BTP tenant. You can find more info about this on SAP blogs like this one:
https://blogs.sap.com/2020/04/03/sap-application-router/
You could also use the sap-cf-localenv command:
https://github.com/jowavp/sap-cf-localenv
This tool is experimental,a s far as I know, this only works for the CF CLI V6. Higher version are fetching the service keys in another format, which leads to the command to fail.
Kind regards,
Thomas