Shortugo

Shortugo is a high-performance URL shortening service written in Go. It provides an API for generating short links, managing user-specific URLs, and interacting with a persistent database.

🚀 Features

• URL shortening (plain text, JSON, batch)
• Retrieve all user URLs
• Delete user URLs
• Expand shortened URLs to original
• Health check endpoint for database connectivity

📋 Endpoints

Method	Path	Description
POST	/	Shorten URL (plain text)
POST	/api/shorten	Shorten URL (JSON)
POST	/api/shorten/batch	Batch URL shortening
GET	/api/user/urls	Retrieve user's URLs
DELETE	/api/user/urls	Delete user's URLs
GET	/{id}	Expand shortened URL
GET	/ping	Check database connectivity

⚙️ Middleware

• RealIP — extracts the real client IP
• Recoverer — handles panics and returns 500 errors
• LogMiddleware — logs requests and responses
• GzipMiddleware — compresses responses using gzip

❌ The RequestID middleware was removed as part of performance optimization.

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⚡ Optimizations

The following changes were made to improve performance:

• 🔥 Removed RequestID middleware
• ⚙️ Replaced json.Marshal with json.NewEncoder(&buf) to reduce memory allocations
• ⚙ Replaced fmt.Sprintf with string concatenation using + to reduce CPU usage.
• 🔧 Modified GzipMiddleware to use a sync.Pool for gzip.Reader, improving performance and reducing GC pressure.

var gzipReaderPool = sync.Pool{
	New: func() any {
		return new(gzip.Reader)
	},
}

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📈 Profiling

📊 Heap Profiling

go tool pprof -top -diff_base=./profile/list_user_urls_heap_base.pprof ./profile/list_user_urls_heap_result.pprof

Result Summary:

File: wgo_20250406124054_1464
Build ID: 6137533df8ba87f1f2ecb5a5bfe7865bc8fd4cbf
Type: inuse_space
Time: 2025-04-06 12:30:00 +05
Duration: 90.04s, Total samples = 111.84MB 
Showing nodes accounting for 12.24MB, 10.94% of 111.84MB total
      flat  flat%   sum%        cum   cum%
  -22.47MB 20.09% 20.09%    ...

🧠 CPU Profiling

go tool pprof -top -diff_base=./profile/list_user_urls_profile_base.pprof ./profile/list_user_urls_profile_result.pprof

Result Summary:

File: wgo_20250406124054_1464
Build ID: 87d19bc98f8b5040a8724bf0462b6d91e5a17db5
Type: cpu
Time: 2025-04-06 12:21:18 +05
Duration: 60.35s, Total samples = 230.69s (382.26%)
Showing nodes accounting for 0.68s, 0.29% of 230.69s total
Dropped 13 nodes (cum <= 1.15s)
      flat  flat%   sum%        cum   cum%
     4.01s  1.74%  1.74%     12.95s  5.61%  runtime.concatstrings
    -3.89s  1.69%  0.052%   -16.02s  6.94%  fmt.(*pp).doPrintf
     3.80s  1.65%  1.70%      4.05s  1.76%  encoding/json.appendString[go.shape.string]
     3.54s  1.53%  3.23%      3.54s  1.53%  internal/runtime/syscall.Syscall6
     3.18s  1.38%  4.61%      3.18s  1.38%  runtime.memclrNoHeapPointers
    -2.37s  1.03%  3.58%    -10.48s  4.54%  fmt.(*pp).printArg
    -2.11s  0.91%  2.67%     -8.29s  3.59%  runtime.mallocgcSmallScanNoHeader
     2.01s  0.87%  3.54%      2.01s  0.87%  runtime.memmove
    -1.80s  0.78%  2.76%     -1.80s  0.78%  runtime.nextFreeFast (inline)
    -1.73s  0.75%  2.01%     -4....

These improvements led to significant reductions in memory usage and CPU time, especially around fmt and encoding/json operations.

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🧪 Usage

Use curl, Postman, or integrate with your frontend/backend services to shorten and manage URLs using the API above.

📄 License

MIT