DevTools

QTap Dev Tools is a browser-based interface for debugging production API calls. It uses the same familiar visual approach as Chrome DevTools, but for a completely different use case: troubleshooting server-side HTTP/S traffic in real-time.

When you need to see exactly what your application is sending to third-party APIs, or why an integration is failing, Dev Tools gives you instant visibility without deploying code changes.

Air-Gapped Ready: DevTools runs entirely on localhost - no external services required. All data stays on your infrastructure, making it ideal for regulated environments and data sovereignty requirements.

---

How to Enable

DevTools is built into the Qtap binary. You simply need to turn it on during startup using a flag or environment variable.

Method	Syntax	Best For
CLI Flag	--enable-dev-tools	Binary usage, Quick demos
Env Var	ENABLE_DEV_TOOLS=true	Docker, Kubernetes, Helm

Once enabled, the interface is accessible at: http://localhost:10001/devtools

---

Deployment Options

1. Quick Start (Temporary)

The fastest way to inspect traffic immediately. This downloads Qtap to /tmp and starts capturing.

# Download and run with DevTools enabled
curl -s https://get.qpoint.io/demo | sudo sh -s -- --enable-dev-tools

2. Production Binary

For persistent installation on a VM or bare metal server.

# 1. Install Qtap
curl -s https://get.qpoint.io/install | sudo sh

# 2. Run with DevTools enabled
sudo qtap --enable-dev-tools

3. Docker

Run Qtap as a privileged container to capture host traffic.

docker run -d --name qtap \
  --user 0:0 --privileged \
  --cap-add CAP_BPF --cap-add CAP_SYS_ADMIN \
  --pid=host --network=host \
  -v /sys:/sys \
  -v /var/run/docker.sock:/var/run/docker.sock \
  -e TINI_SUBREAPER=1 \
  -e ENABLE_DEV_TOOLS=true \
  --ulimit=memlock=-1 \
  us-docker.pkg.dev/qpoint-edge/public/qtap:v0 \
  --log-level=warn

4. Kubernetes / Helm

Add the environment variable to your Pod spec or Helm values.

# In your Pod spec or Helm values
env:
  - name: ENABLE_DEV_TOOLS
    value: "true"

See Kubernetes Installation for full manifest details.

---

Core Use Cases

DevTools is designed for moments when you need to see "ground truth" data immediately.

1. API Integration Debugging

The Problem: A third-party API is returning errors, but your logs don't show the full request context.

DevTools Insight:

• See the exact Authorization header sent (e.g., Did we send Bearer when they expected Basic?).

• Read the full error response body which often contains specific error codes hidden by application logic.

• View request timing to pinpoint latency.

2. Production Incident Response

The Problem: A critical sync process is failing in production, and you can't wait for a deployment cycle to add debug logging.

DevTools Insight:

• SSH into the box, start Qtap, and watch the failure occur in real-time.

• Identify issues like 404 Not Found (endpoint changed) or DNS resolution failures instantly.

• Result: Diagnose the issue in minutes without touching application code.

3. Third-Party Service Changes

The Problem: An integration that worked yesterday is broken today. Did the provider change their API?

DevTools Insight:

• Compare your application's requests (unchanged) against the provider's responses.

• Spot new requirements, such as a missing X-API-Version header or a change in the required payload structure.

4. Webhook Debugging

The Problem: You aren't receiving webhooks from a provider. Is the network blocking them, or is your app rejecting them?

DevTools Insight:

• Verify if the webhook actually reaches the network interface.

• Inspect the signature headers and payload format to ensure they match your validation logic.

---

Remote Access (SSH Tunnel)

Since DevTools listens on localhost for security, use an SSH tunnel to access it on a remote server from your local device.

# 1. Create tunnel (run on your laptop)
ssh -L 10001:localhost:10001 -N user@production-server

# 2. Open browser locally
open http://localhost:10001/devtools

---

Note: You can use DevTools (for real-time viewing) and S3 Storage (for permanent archiving) simultaneously by configuring both in your Qtap settings.