feat(cli): add start-worker command

packages/cli/src/commands/start-worker.ts

@@ -0,0 +1,49 @@
+import { readFileSync } from 'fs';
+import { Command, Flags } from '@oclif/core';
+import * as dotenv from 'dotenv';
+
+export default class StartWorker extends Command {
+  static description = 'Run automatisch worker';
+
+  static flags = {
+    env: Flags.string({
+      multiple: true,
+      char: 'e',
+    }),
+    'env-file': Flags.string(),
+  }
+
+  async prepareEnvVars(): Promise<void> {
+    const { flags } = await this.parse(StartWorker);
+
+    if (flags['env-file']) {
+      const envFile = readFileSync(flags['env-file'], 'utf8');
+      const envConfig = dotenv.parse(envFile);
+
+      for (const key in envConfig) {
+        const value = envConfig[key];
+        process.env[key] = value;
+      }
+    }
+
+    if (flags.env) {
+      for (const env of flags.env) {
+        const [key, value] = env.split('=');
+        process.env[key] = value;
+      }
+    }
+
+    // must serve until more customization is introduced
+    delete process.env.SERVE_WEB_APP_SEPARATELY;
+  }
+
+  async runWorker(): Promise<void> {
+    await import('@automatisch/backend/worker');
+  }
+
+  async run(): Promise<void> {
+    await this.prepareEnvVars();
+
+    await this.runWorker();
+  }
+}