Frequently Asked Questions
Use the Infobip API and Node.js SDK along with Express.js to create an API endpoint that accepts recipient phone numbers and a message, sending it as a bulk SMS broadcast via Infobip's platform. This setup handles the backend logic for sending notifications, alerts, and other mass communications.
The Infobip API and its official Node.js SDK enable efficient sending of SMS messages, WhatsApp messages, and other communications. It integrates smoothly with a Node.js and Express server, streamlining the messaging logic.
Express.js simplifies building a RESTful API endpoint to handle incoming broadcast requests. Its minimal design and widespread adoption make it an ideal framework for managing requests and responses in Node.js SMS applications.
Obtain your API key and base URL from the Infobip dashboard. For local development, store these in a .env file and load them using dotenv. Never commit the .env file. In production, use platform-specific environment variable settings.
Install express, @infobip-api/sdk, and dotenv for core functionality. Nodemon is recommended for development to restart the server automatically on code changes. Optionally, use Prisma and SQLite for a database, and express-rate-limit for rate limiting.
Create folders for routes, controllers, services, and config. Implement controllers to manage requests, services to handle Infobip interactions, and routers to define endpoints. Centralize Infobip configuration, error handling, and API initialization logic in separate files.
The /api/broadcast endpoint accepts POST requests containing an array of recipient phone numbers and the message text. The controller then utilizes the Infobip Service to send the message to all provided numbers via SMS using the Infobip API.
Implement validation in the controller to catch invalid input. The Infobip Service should handle API errors and provide specific messages for detailed logging. Use a global error handler in Express for unhandled errors and avoid leaking sensitive data in production.
Use the express-rate-limit middleware in your Express app to protect the /api/broadcast endpoint from excessive requests. Configure the limits based on your Infobip account limits and expected traffic patterns. Return informative error messages to clients exceeding the rate limit.
Add a GET route, typically at /health, that returns a 200 OK status with a JSON payload like { status: 'UP' }. This allows monitoring systems to quickly check the server's availability. You can also include a timestamp.
Log essential data (e.g., bulkId) for monitoring. Consider using dedicated logging libraries like Winston or Pino for structured logging, log levels, and various output options (files, external services). Avoid logging sensitive details like the full API response body or API key.
Prisma and a database like SQLite (or others like Postgres) offer a persistent record of each broadcast request, including recipient details, message content, timestamps, and Infobip response data (bulkId, individual message statuses). This is essential for auditing and tracking message deliveries.
Use libraries like async-retry or p-retry with exponential backoff and jitter for transient errors like 429 (Too Many Requests). Be cautious with retries for actions like SMS sending; consider idempotency or rely on Infobip's delivery reports for status updates instead of client-side retries.
Test with invalid input, bad phone numbers, or a temporarily wrong API key to see error handling. If possible, use tools like Postman to simulate network issues or trigger Infobip-specific errors to evaluate the robustness of your error logging and response handling.
Customize the "from" parameter in the Infobip API request when you want to display an alphanumeric sender ID (your brand name) instead of a phone number. Check Infobip's regulations for your country, as these IDs are subject to specific restrictions and require prior approval in many regions.
How to Send Bulk SMS with Node.js, Express, and Infobip API
Learn how to build a production-ready bulk SMS broadcast system using Node.js and Express.js with the Infobip API. This comprehensive tutorial covers everything from initial project setup to deploying a scalable SMS messaging service with error handling, database integration, and security best practices.
This guide provides a step-by-step walkthrough for implementing bulk SMS messaging functionality. By the end, you'll have a fully functional Express API endpoint capable of sending SMS messages to multiple recipients simultaneously using Infobip's Node.js SDK.
What You'll Build: Node.js Bulk SMS Service Overview
This guide provides a comprehensive, step-by-step walkthrough for building a production-ready Node.js application using the Express framework to send bulk broadcast SMS messages via the Infobip API. We will cover project setup, core implementation, API design, error handling, security, deployment, and verification.
By the end of this guide, you will have a functional Express API endpoint capable of receiving a list of phone numbers and a message, then efficiently dispatching that message to all recipients using Infobip's robust communication platform.
Project Overview and Goals
What We're Building:
We are creating a backend service built with Node.js and Express. This service will expose a single API endpoint (
/api/broadcast) that accepts a POST request containing:The service will then use the Infobip Node.js SDK to send the specified message to all phone numbers in the list via SMS.
Problem Solved:
This addresses the common need for applications to send notifications, alerts, marketing messages, or other communications to multiple users simultaneously via SMS, leveraging a reliable third-party provider like Infobip for delivery.
Technologies Used:
@infobip-api/sdk): Infobip provides communication APIs (SMS, WhatsApp, etc.). We use their official Node.js SDK for cleaner integration compared to manual HTTP requests..envfile intoprocess.env, essential for managing sensitive credentials securely during local development.System Architecture:
Prerequisites:
@infobip-api/sdkrequires Node.js 14 minimum. Check your version withnode -v.1. Node.js Project Setup and Dependencies
Let's initialize our Node.js project and install the necessary dependencies.
Create Project Directory: Open your terminal and create a new directory for the project, then navigate into it.
Initialize Node.js Project: This creates a
package.jsonfile to manage project details and dependencies.(The
-yflag accepts default settings; you can omit it to customize project details).Install Dependencies: We need Express for the web server, the Infobip SDK for SMS sending, and
dotenvfor environment variable management.Install Development Dependencies (Optional but Recommended):
nodemonautomatically restarts the server on file changes, speeding up development.Create Project Structure: Organize the code logically.
Configure
.gitignore: Prevent committing sensitive files and unnecessary directories.Set up
.envFile: Store sensitive credentials here for local development only. Never commit this file to version control. See Deployment section for production handling.xxxxx.api.infobip.com.Add
startanddevScripts topackage.json: These scripts make running the application easier. Openpackage.jsonand ensure thescriptssection looks like this:2. Implementing Core SMS Functionality with Infobip SDK
We'll encapsulate the Infobip interaction logic within a dedicated service module.
Configure Infobip Client: Create a reusable Infobip client instance.
dotenv.config()loads variables from.env(useful locally). We add checks to ensure critical variables are present.AuthType.ApiKeyexplicitly tells the SDK how to authenticate.Create the Infobip Service: This service will contain the function to send bulk SMS messages.
recipients,messageText). We map the simple array of numbers to thedestinationsarray format expected by the SDK ([{ to: 'number1' }, { to: 'number2' }]). The core logic is theinfobipClient.channels.sms.sendcall. We structure the payload with onemessagesobject containing multipledestinationsfor efficient broadcast. Error handling logs detailed information from the API response if available. A comment advises on more concise production logging.3. Building the Express API Endpoint for Bulk SMS
Now, let's create the Express endpoint that will use our
infobipService.Create the Controller: Handles incoming requests, validates input, calls the service, and sends the response.
infobipService.Create the Route: Defines the API endpoint path and connects it to the controller.
POST) and path (/api/broadcast) to the specific controller function. Keeps routing definitions clean and separate.Set up the Main Server File: Integrates all parts: loads environment variables, configures Express middleware, mounts the router, and starts the server.
express.json()is crucial for parsing the request body. Rate limiting and Helmet (commented out) are vital security measures. Basic logging helps track requests. Mounting the routes under/apinamespaces the API. A health check is standard practice. A global error handler provides a fallback for unexpected issues.4. Configuring Infobip API Integration
This section reinforces the Infobip-specific configuration steps.
Obtaining Credentials:
xyz123.api.infobip.com). This is unique to your account or region.Secure Storage (
.envfor Local Dev):INFOBIP_API_KEYandINFOBIP_BASE_URLin the.envfile at the project root for local development only..env(and variants like.env.local) is listed in your.gitignorefile to prevent accidental commits. Do not deploy.envfiles to production. Use platform environment variables instead (see Section 12).Loading Credentials:
dotenv.config()call at the top ofsrc/config/infobipClient.js(and potentiallysrc/server.jsif needed early) loads these variables intoprocess.envwhen running locally. In deployed environments,process.envwill be populated by the platform.SDK Initialization (
src/config/infobipClient.js):Infobipclass is instantiated with thebaseUrl,apiKey, andauthType: AuthType.ApiKey. This configures the shared client instance used byinfobipService.js.Environment Variables Explained:
INFOBIP_API_KEY: (String) Your secret key for authenticating requests with the Infobip API. Format: Typically a long alphanumeric string. Obtain from Infobip dashboard. Treat as highly sensitive.INFOBIP_BASE_URL: (String) The specific domain assigned to your Infobip account for API requests. Format:subdomain.api.infobip.com. Obtain from Infobip dashboard.PORT: (Number) The network port your Express server will listen on. Format: Integer (e.g., 3000, 8080). Set according to your environment needs or platform requirements.NODE_ENV: (String) Typically set toproductionin deployed environments,developmentlocally. Used by Express and other libraries to optimize behavior (e.g., caching, error details).5. Error Handling and Logging Best Practices
Production systems need robust error handling and logging.
Consistent Error Strategy:
400 Bad Requestwith clear JSON messages indicating the specific input issue (as shown inbroadcastController.js).infobipService.jscatches errors from the SDK. It logs the detailed error (often including Infobip's specific error message) and throws a new, more general error. The controller catches this and returns500 Internal Server Error(or potentially other 4xx/5xx codes if more specific error types were identified and mapped).server.jscatches anything missed (e.g., errors in middleware, unhandled promise rejections if not using modern Node/Express error handling), logs it, and returns a generic500error message to avoid leaking implementation details.Logging:
console.logfor request tracing and info, andconsole.errorfor errors. Suitable for development, but limited in production.WinstonorPino. They provide:error,warn,info,debug) to control verbosity and filter logs.Retry Mechanisms:
429 Too Many Requests,5xxserver errors).async-retryorp-retry. Implement exponential backoff (wait progressively longer between attempts: 1s, 2s, 4s...) with jitter (randomness) to avoid thundering herd issues. Limit the number of retries.2xxacceptance and monitoring via Delivery Reports (Section 10) might be safer and simpler than complex client-side retry logic.Testing Error Scenarios:
recipientsormessage.INFOBIP_API_KEYin environment variables to trigger authentication errors.curl(see Section 13) to manually trigger these conditions.6. Database Integration with Prisma ORM (Optional)
While not essential for the core broadcast function, logging results to a database provides auditability and tracking. We'll use Prisma ORM with SQLite for this example.
Install Prisma:
Initialize Prisma:
prisma/schema.prismaand updates.envwithDATABASE_URL=""file:./dev.db"". Ensuredev.dbis in.gitignore.Define Schema (
prisma/schema.prisma): Model the broadcast jobs and their individual message results.BroadcastJob(1) -> (*)MessageResult. Added indexes for common query fields. AddedonDelete: Cascadeso deleting a job removes its results.Apply Migrations: Create the database file (
dev.db) and apply the schema changes.prisma/migrationsand updates the database.Create Prisma Client Instance: A reusable client instance.
Update Controller to Log Data: Modify
handleBroadcastRequestto interact with the database.BroadcastJobrecord before calling Infobip, updates it with thebulkIdand individual message statuses on success, or updates it with an error status on failure. This provides a persistent record of each attempt and its outcome. Includes basic error handling for the database update itself.