After some headache and trying I found a quite easy way to solve swish-payments through cloud functions:
Using request-js instead of the built in libraries, I only need to build the options object to use in the request.post() method as following:
const swishOptions = {
url: 'LINK TO SWISH SERVER',
json: true,
pfx: fs.readFileSync('cert.p12'),
passphrase: 'swish',
body: swishRequestBody
}
The cert.p12-file should be placed in the same folder as index.js and will be uploaded together with the functions.
rq.post(swishOptions, (err, res) => {
if (err){
console.log('payment creation error: ' + JSON.stringify(err))
reject(err)
}
if (res){
console.log('Payment-token: ' + res.headers.paymentrequesttoken)
}
});
The body-object should contain all fields specified in the Swish API, use console.log() to read the error-messages from the Swish-server.