index.js

const FormData = require('form-data');
const core = require('@actions/core');
const fs = require('fs');

const host = 'dev.larawatch.com';
const protocol = 'https:';
const path = '/api/uploadphpstan';
const filePath = core.getInput('filePath');
const data = core.getInput('data');

console.info('endpoint', host + path);

try {
    fs.existsSync(filePath);
    console.info('File found', filePath);
} catch (e) {
    return core.setFailed('ERROR: file not found: ' + filePath);
}

const form = new FormData();
form.append('file', fs.createReadStream(filePath));
form.append('data', data);

form.getLength(function (err, l) {
    console.info('Sending file, size:', l + 'b');
});

form.submit({ host, protocol, path }, function (err, res) {
    if (err) {
        console.error(err);
        return core.setFailed('Request failed');
    }

    console.info('Response', res.statusCode, res.statusMessage);

    if (res.statusCode >= 400 && res.statusCode < 600) {
        core.setFailed('Request failed');
    }
});