Incomplete Response Body in handleUpstreamResponse

[stanleydv12]

Incomplete Response Body in handleUpstreamResponse

Description

The server intermittently returns incomplete or empty response bodies, particularly with responses larger than 4KB.

Steps to Reproduce

1. Start the server:

   docker compose up --build

2. Make requests to an endpoint that returns >4KB:

   curl -v http://localhost:8080/get

3. Repeat multiple times

Expected Behavior

Consistently returns complete response body for every request.

Actual Behavior

• Sometimes returns complete response
• Sometimes returns partial/empty response
• No errors logged

Environment

• OS: Linux Docker
• Go Version: go1.23.2
• Commit: c6a947a

Root Cause

handleUpstreamResponse in internal/server/server.go uses a fixed 4KB buffer and doesn't handle:

• Responses larger than buffer size
• Chunked transfer encoding
• Partial reads/writes

Proposed Fix

1. Implement dynamic buffering for large responses
2. Add chunked transfer encoding support
3. Handle partial reads/writes
4. Improve error logging

Severity

High - Affects response reliability

Reproduction Rate

Intermittent (happens sometimes, not always)