Re: printf-like output for gnunet-search

[madmurphy]

Okay, after thinking about it I did not like that the --verbose argument was ignored when a format was specified. But since, as it turns out, the --verbose argument was just a way to print all the metadata, I have added an argument for formatting the metadata too. So now we are even. In the meanwhile I have also renamed the new arguments and the format specifiers.

Again, the help page will explain the new situation:

$ gnunet-search --help

gnunet-search [OPTIONS] KEYWORD
Search GNUnet for files that were published on GNUnet
Arguments mandatory for long options are also mandatory for short options.
  -a, --anonymity=LEVEL      set the desired LEVEL of receiver-anonymity
  -c, --config=FILENAME      use configuration file FILENAME
  -F, --dir-printf=FORMAT    write the search results for directories
                               according to FORMAT, where %f is the
                               directory's name, %u is the directory's URI, %m
                               is the directory's mime type (always equal to
                               `application/gnunet-directory`), %n is the
                               search result number and %a is the complete
                               list of all the printable metadata available,
                               in which each field is displayed according to
                               the --prop-printf argument; if missing defaults
                               to the --printf argument; if the latter is
                               missing too defaults to `#%n:\ngnunet-download
                               -o "%f" -R %u\n\n`
  -f, --printf=FORMAT        write the search results according to FORMAT,
                               where %f is the file's name, %u is the file's
                               URI, %m is the file's mime type, %n is the
                               search result number and %a is the complete
                               list of all the printable metadata available,
                               in which each field is displayed according to
                               the --prop-printf argument; if missing defaults
                               to `#%n:\ngnunet-download -o "%f" %u\n\n`
  -h, --help                 print this help
  -L, --log=LOGLEVEL         configure logging to use LOGLEVEL
  -l, --logfile=FILENAME     configure logging to write logs to FILENAME
  -N, --results=VALUE        automatically terminate search after VALUE
                               results are found
  -n, --no-network           only search the local peer (no P2P network
                               search)
  -o, --output=PREFIX        write search results to file starting with PREFIX
  -p, --prop-printf=FORMAT   when the %a format specifier appears in --printf
                               or --dir-printf, list each property according
                               to FORMAT, where %p is the property's content,
                               %l is the property's length in bytes, %t is the
                               property type, %i is the property type's unique
                               identifier and %w is the name of the plugin
                               that provided the information; if missing
                               defaults to `\t%t: %p\n`
  -t, --timeout=DELAY        automatically terminate search after DELAY
  -V, --verbose              be verbose
  -v, --version              print the version number
Report bugs to gnunet-developers@gnu.org.
Home page: http://www.gnu.org/s/gnunet/
General help using GNU software: http://www.gnu.org/gethelp/

Now, besides the obvious question “Do you like the idea?”, I would like also to ask a few other questions too:

1. What do you think about the fact that I have named the new arguments --printf, --dir-printf and --prop-printf? Do you think that alternative names would be better?
2. What do you think about the fact that the format specifiers for --printf and --dir-printf use these letters? Do you think that other letters would be more obvious?
   
   • %f – the file's name
   • %u – the file's URI
   • %m – the file's mime type
   • %n – the search result number
   • %a – the complete list of all the printable metadata available
3. What do you think about the fact that the format specifiers for --prop-printf use these other letters?
   
   • %p – the property's content
   • %l – the property's length in bytes
   • %t – the property type
   • %i – the property type's unique identifier
   • %w – where the information came from
4. Do you think that the help page is clear enough?
5. Do you like the idea?

I really hope that my proposal does not sound intrusive and actually you like this idea as much as I do. Providing printf-like arguments gives infinite possibilities for shell scripting.

Once again, please find attached a patch, or alternatively the single file that I have edited.

P.S. Since it is a standalone program, if you want to play with this patched version without having to recompile the entire GNUnet, you can just launch:

unzip gnunet-search.rev2.zip
ln -s /usr/include/gnunet/gnunet_fs_service.h gnunet_fs_service.h 
ln -s /usr/include/gnunet/platform.h platform.h
gcc -lgnunetutil -lgnunetfs -I/usr/include/gnunet -o 'gnunet-search-test' gnunet-search.c
./gnunet-search-test -f '%n. %f\n' 'commons'

(if you follow these steps the program will be compiled without libextractor and the %t specifier in --prop-printf will not be available.)

--madmurphy

On Fri, Feb 4, 2022 at 6:21 PM madmurphy <madmurphy333@gmail.com> wrote:

Hi GNUnet folks!

I have edited the gnunet-search utility to accept a --format and a --dir-format parameters and produce a printf-like output. It was pretty easy to do, I only had to edit gnunet/src/fs/gnunet-search.c. The new text printed by gnunet-search --help can explain the two new arguments in detail:

$ gnunet-search --help

gnunet-search [OPTIONS] KEYWORD
Search GNUnet for files that were published on GNUnet
Arguments mandatory for long options are also mandatory for short options.
  -a, --anonymity=LEVEL      set the desired LEVEL of receiver-anonymity
  -c, --config=FILENAME      use configuration file FILENAME
  -F, --dir-format=DIRFORMAT write search results for directories according to
                               DIRFORMAT, where %n is the result number, %f is
                               the file's name and %u is the file's URI; if
                               missing defaults to FORMAT; if the latter is
                               missing too defaults to '#%n:\ngnunet-download
                               -o "%f" -R %u\n\n'
  -f, --format=FORMAT        write search results according to FORMAT, where
                               %n is the result number, %f is the file's name
                               and %u is the file's URI; if missing defaults
                               to '#%n:\ngnunet-download -o "%f" %u\n\n')
  -h, --help                 print this help
  -L, --log=LOGLEVEL         configure logging to use LOGLEVEL
  -l, --logfile=FILENAME     configure logging to write logs to FILENAME
  -N, --results=VALUE        automatically terminate search after VALUE
                               results are found
  -n, --no-network           only search the local peer (no P2P network
                               search)
  -o, --output=PREFIX        write search results to file starting with PREFIX
  -t, --timeout=DELAY        automatically terminate search after DELAY
  -V, --verbose              be verbose
  -v, --version              print the version number
Report bugs to gnunet-developers@gnu.org.
Home page: http://www.gnu.org/s/gnunet/
General help using GNU software: http://www.gnu.org/gethelp/

Basically with this new patch launching

gnunet-search commons

and launching

gnunet-search --format='#%n:\ngnunet-download -o "%f" %u\n\n' \
	--dir-format='#%n:\ngnunet-download -o "%f" -R %u\n\n' \
	commons

are equivalent.

What do you think? I hope you like the idea.

I have done my best to stick to the coding style of the rest of the program. But a good code review is more than welcomed.

Please find attached a patch, or alternatively the single file I have edited.

--madmurphy

gnunet-search.patch2.zip
Description: Zip archive

gnunet-search.rev2.zip
Description: Zip archive