[Bug] Unhandled JSON.parse() in MongoDB config can crash application on startup

[smirk-dev]

Problem Statement

The MongoDB configuration file (apps/meteor/packages/rocketchat-mongo-config/server/index.js) contains an unprotected JSON.parse() call that will crash the entire application on startup if the MONGO_OPTIONS environment variable contains invalid JSON.

Current Behavior

Location: apps/meteor/packages/rocketchat-mongo-config/server/index.js:30

const mongoOptionStr = process.env.MONGO_OPTIONS;
if (typeof mongoOptionStr !== 'undefined') {
    const mongoOptions = JSON.parse(mongoOptionStr);  // ❌ No error handling
    Object.assign(mongoConnectionOptions, mongoOptions);
}

What happens:

• If MONGO_OPTIONS is set to invalid JSON (e.g., MONGO_OPTIONS='{"invalid": json}'), the application crashes immediately on startup
• No graceful error message is shown
• The application cannot start until the environment variable is fixed
• This affects production deployments where env vars might be misconfigured

Expected Behavior

The JSON parsing should be wrapped in a try-catch block with:

1. ✅ Graceful error handling
2. ✅ Clear error message indicating the invalid JSON
3. ✅ Fallback to safe defaults or graceful shutdown with helpful diagnostics

Proposed Solution

const mongoOptionStr = process.env.MONGO_OPTIONS;
if (typeof mongoOptionStr !== 'undefined') {
    try {
        const mongoOptions = JSON.parse(mongoOptionStr);
        Object.assign(mongoConnectionOptions, mongoOptions);
    } catch (error) {
        console.error('Failed to parse MONGO_OPTIONS environment variable:', error.message);
        console.error('MONGO_OPTIONS value:', mongoOptionStr);
        console.error('Please ensure MONGO_OPTIONS contains valid JSON');
        throw new Error(`Invalid MONGO_OPTIONS: ${error.message}`);
    }
}

Impact Assessment

Severity: High

• 💥 Application crash - Complete failure to start
• 🔧 Critical path - MongoDB configuration runs early in startup sequence
• 🚨 Production risk - Misconfigured env vars can take down entire deployment
• 🐛 Poor debuggability - Generic JSON parsing error without context

Affected deployments:

• Docker containers with misconfigured environment variables
• Kubernetes deployments during configuration updates
• CI/CD pipelines with templating errors
• Manual deployments with typos in env vars

Steps to Reproduce

1. Set invalid JSON in MONGO_OPTIONS environment variable:

   export MONGO_OPTIONS='{"invalid": json}'

2. Start Rocket.Chat application

3. Observe crash:

   SyntaxError: Unexpected token j in JSON at position 12
       at JSON.parse (<anonymous>)
       at packages/rocketchat-mongo-config/server/index.js:30
   

Environment

• Affected versions: All versions (checked develop branch)
• Component: MongoDB configuration (Meteor package)
• Deployment: All deployment methods (Docker, bare metal, Kubernetes)

Additional Context

This is part of the early startup sequence, so there's no opportunity for the application to recover or provide user-friendly diagnostics. The error surfaces as a cryptic stack trace rather than a clear configuration error message.

Related Files

• apps/meteor/packages/rocketchat-mongo-config/server/index.js (main issue)

Acceptance Criteria

• JSON.parse() wrapped in try-catch block
• Clear error message when MONGO_OPTIONS is invalid JSON
• Error message includes the invalid value for debugging
• Application fails fast with actionable error message
• Tests added for invalid JSON handling
• Documentation updated if needed

Priority

High - This affects application availability and can cause production outages during deployment/configuration changes.

[shash-hq]

Hello! I've analyzed this issue regarding the JSON.parse crash on startup. Given its critical impact on service start reliability, I am looking forward to fixing this issue.

[smirk-dev]

@shash-hq i have already created a pull request for this issue, and it is in the process of getting merged, you can look at the associated pull request to see how i have solved the issue