qr-code-service

   

A k8s ready http service for QR code generation

Endpoints

• /encode Generate and return qr-code png
• /delete Delete all files
• /files List available files
• /metrics Prometheus metrics endpoint
• /healthy Health check: Readiness
• /healthz Health check: Liveness

Usage

Run service

$ ./qr_service --help
usage: qr_service [-h] [--listen-address LISTEN_ADDRESS]
                  [--listen-port LISTEN_PORT] [--disable-delete-files]
                  [--disable-list-files] [--debug]

optional arguments:
  -h, --help            show this help message and exit
  --listen-address LISTEN_ADDRESS
                        The address to listen on
  --listen-port LISTEN_PORT
                        The port to listen on
  --disable-delete-files
                        Disable file deletion
  --disable-list-files  Disable file listing
  --debug               Show debug output

Run container

$ podman run
[output]

Create QR-Code

A GET request to the /encode endpoint with optional url, size and margin parameters to encode the given URL immediately returns a png encoded image file

$ export LISTEN_ADDRESS=localhost; \
  export LISTEN_PORT=44123; \
  export URL=https://[::1]; \
  export SIZE=20; \
  curl -O http://${LISTEN_ADDRESS}:${LISTEN_PORT}/encode?url={${URL}&size=${SIZE}

Generated files land in the static/ directory and can also be fetched from there.
The directory does not get emptied automatically.
A request to /delete removes all png files in this location, if enabled

List generated files on server

A call to the /files endpoint returns JSON containing all present png files at the static location

$ export LISTEN_ADDRESS=localhost; \
  export LISTEN_PORT=44123; \
  curl http://${LISTEN_ADDRESS}:${LISTEN_PORT}/files

Clean-up files on server

A call to the /delete endpoint deletes all present png files at the static location

$ export LISTEN_ADDRESS=localhost; \
  export LISTEN_PORT=44123; \
  curl http://${LISTEN_ADDRESS}:${LISTEN_PORT}/delete

Metrics

A /metrics endpoint for Prometheus exists

$ export LISTEN_ADDRESS=localhost; \
  export LISTEN_PORT=44123; \
  curl http://${LISTEN_ADDRESS}:${LISTEN_PORT}/metrics

Run tests

bash_unit is used to run the tests

$ make test
./tests/install_bash_unit.sh
bash_unit test framework exists
./bash_unit
./bash_unit tests/test_qr_code_service.sh
Running tests in tests/test_qr_code_service.sh
Starting qr-code-service
Running test_qr_delete... SUCCESS ✓
Running test_qr_encode... SUCCESS ✓
Running test_qr_healthy... SUCCESS ✓
Running test_qr_healthz... SUCCESS ✓
Running test_qr_list... SUCCESS ✓
Running test_qr_service_running... SUCCESS ✓
Stopping qr-code-service (84054)

References

Wikipedia: QR code
libqrencode