A HTTP microservice that provides a checksum to POSTed data. POST data to it, and it will send you back a checksum.

If you have wanted to experiment with building a microservice in Rust, this might be useful as an example.

Run the executable:

$ ROCKET_ENV=prod microservice-checksum
🔧 Configured for production.
    => address: 0.0.0.0
    => port: 8000
    => log: critical
    => workers: 24
    => secret key: generated
    => limits: forms = 32KiB
    => keep-alive: 5s
    => tls: disabled
Warning: environment is 'production', but no `secret_key` is configured
🚀 Rocket has launched from http://0.0.0.0:8000

microservice-checksum supports 3 endpoints: /crc16, /crc32, /crc64. From a new console window, you can POST data with curl via the -d option.

$ curl localhost:8000/crc32 -d 'hello?'
1619653635

$ curl localhost:8000/crc64 -d 'yes!'
6344572155291762688

$ curl localhost:8000/crc16 -d 'that was easy'
15643

(CRC16 comes last because it's the least likely to be used. Sorry CRC16.)

Each endpoint supports using custom polynomials if you wish to be specific:

CRC16

/crc16?polynomial=usb (default)

/crc16?polynomial=x25

/crc16?polynomial=n where n [0, 65,535] inclusive

CRC32

/crc16?polynomial=ieee (default)

/crc16?polynomial=castagnoli

/crc16?polynomial=koopman

/crc16?polynomial=n where n [0, 4,294,967,295] inclusive

CRC64

/crc64?polynomial=ecma (default)

/crc64?polynomial=iso

/crc64?polynomial=n where n [0, 18,446,744,073,709,551,615] inclusive

Your client should expect a response within 3ms. Usually it's closer to 1.

Install Rust, git (just in case) and GCC (Rust needs its linker)

sudo apt install build-essential git
curl -fsSL https://sh.rustup.rs | sh

Install microservice-checksum:

cargo install --git https://github.com/timClicks/microservice-checksum

Install the pre-requisites

sudo apt install musl-tools 
rustup target add x86_64-unknown-linux-musl

Build the binary:

git clone https://github.com/timClicks/microservice-checksum
cd microservice-checksum
cargo build --release --target x86_64-unknown-linux-musl

Verify:

target/x86_64-unknown-linux-musl/release/microservice-checksum

I did none of the hard work for this. Please thank the maintainers of the rocket and crc crates.