Refactor the app to use Express server and Jest for tests

src/server.ts

@@ -0,0 +1,49 @@
+import log from './services/log'
+import {testWebBrowserInstallation} from "./services/sessions";
+
+const app = require("./app");
+const version: string = require('../package.json').version
+const serverPort: number = Number(process.env.PORT) || 8191
+const serverHost: string = process.env.HOST || '0.0.0.0'
+
+function validateEnvironmentVariables() {
+  // ip and port variables are validated by nodejs
+  if (process.env.LOG_LEVEL && ['error', 'warn', 'info', 'verbose', 'debug'].indexOf(process.env.LOG_LEVEL) == -1) {
+    log.error(`The environment variable 'LOG_LEVEL' is wrong. Check the documentation.`);
+    process.exit(1);
+  }
+  if (process.env.LOG_HTML && ['true', 'false'].indexOf(process.env.LOG_HTML) == -1) {
+    log.error(`The environment variable 'LOG_HTML' is wrong. Check the documentation.`);
+    process.exit(1);
+  }
+  if (process.env.HEADLESS && ['true', 'false'].indexOf(process.env.HEADLESS) == -1) {
+    log.error(`The environment variable 'HEADLESS' is wrong. Check the documentation.`);
+    process.exit(1);
+  }
+  // todo: fix resolvers
+  // try {
+  //   getCaptchaSolver();
+  // } catch (e) {
+  //   log.error(`The environment variable 'CAPTCHA_SOLVER' is wrong. ${e.message}`);
+  //   process.exit(1);
+  // }
+}
+
+// Init
+log.info(`FlareSolverr ${version}`);
+log.debug('Debug log enabled');
+
+process.on('SIGTERM', () => {
+  // Capture signal on Docker Stop #158
+  log.info("Process interrupted")
+  process.exit(0)
+})
+
+validateEnvironmentVariables();
+
+testWebBrowserInstallation().then(() => {
+  // Start server
+  app.listen(serverPort, serverHost, () => {
+    log.info(`FlareSolverr v${version} listening on http://${serverHost}:${serverPort}`);
+  })
+})