Rocket.Chat/app/apps/server/bridges/environmental.ts

import { EnvironmentalVariableBridge } from '@rocket.chat/apps-engine/server/bridges/EnvironmentalVariableBridge';

import { AppServerOrchestrator } from '../orchestrator';

export class AppEnvironmentalVariableBridge extends EnvironmentalVariableBridge {
	allowed: Array<string>;

	// eslint-disable-next-line no-empty-function
	constructor(private readonly orch: AppServerOrchestrator) {
		super();
		this.allowed = ['NODE_ENV', 'ROOT_URL', 'INSTANCE_IP'];
	}

	protected async getValueByName(envVarName: string, appId: string): Promise<string | undefined> {
		this.orch.debugLog(`The App ${ appId } is getting the environmental variable value ${ envVarName }.`);

		if (!await this.isReadable(envVarName, appId)) {
			throw new Error(`The environmental variable "${ envVarName }" is not readable.`);
		}

		return process.env[envVarName];
	}

	protected async isReadable(envVarName: string, appId: string): Promise<boolean> {
		this.orch.debugLog(`The App ${ appId } is checking if the environmental variable is readable ${ envVarName }.`);

		return this.allowed.includes(envVarName.toUpperCase());
	}

	protected async isSet(envVarName: string, appId: string): Promise<boolean> {
		this.orch.debugLog(`The App ${ appId } is checking if the environmental variable is set ${ envVarName }.`);

		if (!await this.isReadable(envVarName, appId)) {
			throw new Error(`The environmental variable "${ envVarName }" is not readable.`);
		}

		return typeof process.env[envVarName] !== 'undefined';
	}
}