Home/ Projects/ Backend/Caching Proxy Server from Scratch

Step-by-step guideAdvancedBackend Estimated: Weekend Est. 8h total

Progress:

Caching Proxy Server from Scratch

Custom caching proxy server returning cached responses for identical endpoints requests.

Tech Stack:Node.jsExpressRedisAxios

Roadmap Steps

Key Features

Concepts

Tech Stacks

Common Pitfalls

Prequisites

Interactive Project Checklist

Tick off requirements as you build to track real-time completion.

Completed

Step-by-Step Development Roadmap

Follow this chronological guide to build the project from scratch.

0 / 4 Steps Completed

Step 1

Redis Proxy Router foundations

3 key tasks

Intercept requests and connect backend cache client.

Key Implementation Tasks

Initialize Express server routing wildcards (/*)
Configure connection client to local Redis instance
Integrate axios request client to forward queries to origin

Step 2

Caching Middleware Implementation

3 key tasks

Step 3

Admin Utilities & Cache Clears

3 key tasks

Step 4

Header Filtering & Deploy

3 key tasks

Common Challenges & Debugging Solutions

Real issues students hit during development and how to troubleshoot them fast.

State Management

Inconsistent Cache invalidations

Issue: Serving stale data from cache after origin database updates.

Fix Solution:Enforce cache-control expiration parameters (setEx) and expose cache clearing webhooks.

State Management

Large Response Buffer Memory Leaks

Issue: Caching large binary payloads or multi-megabyte JSONs runs out of memory or blocks node main event loop.

Fix Solution:Check Content-Length header first. If payload exceeds 5MB, bypass Redis cache entirely and pipe streams directly from origin to client.

API Errors

Forwarding Request Hop Headers Collapse

Issue: Forwarding the raw request headers from proxy directly causes the target origin to respond with compression mismatches or connection shutdowns.

Fix Solution:Filter out connection-specific HTTP/1.1 headers before forwarding, allowing axios or http client to assign new footprints.

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Home/ Projects/ Backend/Caching Proxy Server from Scratch

Step-by-step guideAdvancedBackend Estimated: Weekend Est. 8h total

Progress:

Caching Proxy Server from Scratch

Custom caching proxy server returning cached responses for identical endpoints requests.

Tech Stack:Node.jsExpressRedisAxios

Roadmap Steps

Key Features

Concepts

Tech Stacks

Common Pitfalls

Prequisites

Interactive Project Checklist

Tick off requirements as you build to track real-time completion.

Completed

Step-by-Step Development Roadmap

Follow this chronological guide to build the project from scratch.

0 / 4 Steps Completed

Step 1

Redis Proxy Router foundations

3 key tasks

Intercept requests and connect backend cache client.

Key Implementation Tasks

Initialize Express server routing wildcards (/*)
Configure connection client to local Redis instance
Integrate axios request client to forward queries to origin

Step 2

Caching Middleware Implementation

3 key tasks

Step 3

Admin Utilities & Cache Clears

3 key tasks

Step 4

Header Filtering & Deploy

3 key tasks

Common Challenges & Debugging Solutions

Real issues students hit during development and how to troubleshoot them fast.

State Management

Inconsistent Cache invalidations

Issue: Serving stale data from cache after origin database updates.

Fix Solution:Enforce cache-control expiration parameters (setEx) and expose cache clearing webhooks.

State Management

Large Response Buffer Memory Leaks

Issue: Caching large binary payloads or multi-megabyte JSONs runs out of memory or blocks node main event loop.

Fix Solution:Check Content-Length header first. If payload exceeds 5MB, bypass Redis cache entirely and pipe streams directly from origin to client.

API Errors

Forwarding Request Hop Headers Collapse

Issue: Forwarding the raw request headers from proxy directly causes the target origin to respond with compression mismatches or connection shutdowns.

Fix Solution:Filter out connection-specific HTTP/1.1 headers before forwarding, allowing axios or http client to assign new footprints.

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