exiftool2json

README

programmfabrik - exiftool2json

Process the output of exiftool -listx command converting that to a valid JSON document.

Building it

Just invoke go build .

Running it

The app will perform some self-diagnose tests to verify if the required tool is available exiftool, if not, a message will be printed and the application will abort without any further action.

After that it will try to setup a webserver at 0.0.0.0:8080, you can change the parameters using command line flags. Use -h for more details

Closing it

The app will run until it receives a SIGTERM (Ctrl+C in any UNIX)

Working on it

If you have make and modd installed, use make watch to recompile the app every time a .go file is changed. Otherwise, just call go build from time.

Future improvements

Currently, there is no limit to how many instances of exiftool are running at any given moment, thus, the service should be executed behind a proxy to add some form of rate-limit.

• Alternatively, one could implement a semaphore in exif.Tool#WalkTags using buffered channels. The size of the channel would indicate the max number of instances that should be executed at any given moment.

• It might be possible to improve the parsing code so that xml.Decoder#DecodeElement could be used. But care must be taken to avoid using xml.Decoder#Token at the root level. Otherwise, the whole XML will be processed (as that method provides guarantees regarding which tags are closed)

• exif.Tool#WalkTags doesn't use channels. This is a design decision, otherwise callers would need to deal with the added concurrency. By relying on a blocking API, callers have the choice to use it either sync or async.

• Allocation could be reduced in the JSON encoding block by implementing MarshalJSON for some types, but this might make the code less readable.