Understanding API Security in Frontend Development: My Experience and Insights

As a React frontend intern, I recently encountered a situation where my manager and senior DevOps engineer emphasized the importance of concealing API endpoints and keys within the frontend code. They expressed concern that these details should not be accessible via the browser’s developer tools, such as Network and Sources tabs.

The Challenge: Frontend Transparency and Security Concerns

In brief, their goal was to ensure that sensitive API URLs and keys—notably session identifiers—are not visible or easily accessible to end-users. Specifically, they requested:

• API endpoints should not appear in the browser’s Sources tab.
• API keys should be hidden or encrypted within requests.
• Session ID information should not be exposed in network traffic.

I want to clarify the data flow involved:

• My frontend makes web requests to a backend server.
• The backend responds with data, including fields like data and session_id.
• The DevOps team’s concerns involve:
• Preventing session IDs from being stored or visible in the network.
• Hiding or encrypting API URLs and keys used in requests.

Is Hiding API Keys Truly Feasible?

After researching and consulting various developer forums like Reddit and Stack Overflow, I found a consistent answer: it’s fundamentally impossible to completely hide API keys or endpoints within client-side code. Anything sent to the browser—whether in JavaScript, source code, or network requests—is ultimately accessible to users.

Obfuscation techniques can make it less straightforward to locate keys, but they do not provide real security. API keys used solely for identification (not authorization) are often embedded in frontend code, knowing they can be exposed, since protection at this layer is limited.

Key Clarifications and Best Practices

• Separation of Concerns:
  Instead of trying to hide API endpoints or keys in frontend code, the recommended approach is to handle sensitive operations on the server side. Implement a backend proxy or middleware that interacts with the real API, so the frontend communicates with your server, not directly with third-party services.

• Session Management:
  Session IDs should be managed securely. Attributes like HttpOnly cookies are set server-side to prevent access from JavaScript, adding a layer of protection.

• Reducing Exposure of Sensitive Data:
  Only include public or non-sensitive data in your frontend code. If certain keys are essential for client-side use, acknowledge that they may be visible