Download metadata only

[r-gcc-65061]

Could there be an option to only download the metadata obtained with the --write* flag? Currently it only does so if the image downloaded successfully, and the --dump-json option dumps all the information from JSON without following the name and format configurations.

[r-gcc-65061]

As an addendum, my apologies, would it be possible to implement it in such a way that would allow the "--option skip-false" flag's passing to apply for downloading metadata files also, since if the file already exists or is indicated as downloaded, the metadata downloading or the postprocessor seems to be skipped too.

[mikf]

There is now a --no-download flag as well as a download option that allows you to disable file downloads while everything else works as normal. Some post-processor modules might raise an exception when running them without having downloaded a file, but --write-metadata definitely works.

And yes, you need to pass -o skip=false if you want to run post-processors for previously downloaded files. The "does the file already exist?" check still happens.