The project exposes a REST controller with a single endpoint that accepts an URL to an mp4 file as a parameter - sent as the value of the X-VIDEO-URL header - then reads the file at that location and returns the json representation of the file contents as a series nested atoms.
The project ships with two implementations for an mp4 file parser: standard and reactive.
standard implementation reads the file contents as a continuous stream of bytes which is processes on the fly to extract the atoms.
reactive implementation uses Netty to read the file, partition it's contents in variable sized frames - one per each root atom - which is then returned and processed as a Flux of objects. Each frame has the length indicated by the corresponding atom's length metadata; the frames are processed using a custom ByteToMessageDecoder implementation at AtomFrameDecoder.
The implementation does not validate the file structure, if the indicated file is not a valid mp4 file then the service will error or return inconsistent data.
The project requires Maven and JRE 17 to run.
On Unix systems to start the application simply run the following command (Maven needs to be installed on the system):
mvn spring-boot:runOn Windows systems the wrapper supplied with the app can be used:
./mvnw spring-boot:runBy default the app runs in standard mode; to run it in reactive mode change the value of the mp4.analyzer.read.strategy parameter to reactive as such:
mvn spring-boot:run -Dspring-boot.run.arguments=--mp4.analyzer.read.strategy=reactiveThe app ships with some unit and integration tests for the standard and reactive implementations; the following command will run the test suite:
mvn clean testTo manually make a request using curl start the application and then run the following command:
curl -H "X-VIDEO-URL: http://example.com/test.mp4" http://localhost:8080For any other HTTP/Rest client just set the X-VIDEO-URL header value to the URL of the file to be analyzed.