A high-performance REST API service written in Rust that provides city and state information for US postal codes (ZIP codes). The service loads postal code data from a CSV file into memory and serves requests using a thread pool for optimal performance.
- Fast in-memory ZIP code lookups
- RESTful GET endpoint
- Thread pool for concurrent request handling
- Response caching headers
- Optimized for high throughput
- Worker count based on CPU cores
- Rust (latest stable version)
- CSV file with postal code data (
ZIP_Locale_Detail.csv)
- Clone the repository:
git clone <repository-url>
cd postal-service- Build the project:
cargo build- Run the project:
cargo run --release- Test the project:
cargo test- Run the project:
cargo run --releaseThe service will:
- Load the ZIP code database into memory
- Print the number of loaded ZIP codes
- Start the HTTP server on
http://127.0.0.1:8080
GET /location/{postal_code}
Response
{
"city": "ADJUNTAS",
"state": "PR"
}
The service is optimized for performance with:
- Pre-allocated HashMap for ZIP code data
- Thread pool for request handling
- Response caching (24-hour cache headers)
- Keep-alive connections
- Worker optimization based on CPU cores
The service expects a CSV file (ZIP_Locale_Detail.csv) with the following columns:
- Column 4: DELIVERY ZIPCODE
- Column 7: PHYSICAL CITY
- Column 8: PHYSICAL STATE
You can download the XLS of this file from the USPS website: https://postalpro.usps.com/ZIP_Locale_Detail and then convert it to CSV using Excel.