Section: User Contributed Perl Documentation (1p)
Updated: 2011-11-07
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json_xs - JSON::XS commandline utility  


   json_xs [-v] [-f inputformat] [-t outputformat]



json_xs converts between some input and output formats (one of them is JSON).

The default input format is "json" and the default output format is "json-pretty".  


Be slightly more verbose.
-f fromformat
Read a file in the given format from STDIN.

"fromformat" can be one of:

json - a json text encoded, either utf-8, utf16-be/le, utf32-be/le
storable - a Storable frozen value
storable-file - a Storable file (Storable has two incompatible formats)
bencode - use Convert::Bencode, if available (used by torrent files, among others)
clzf - Compress::LZF format (requires that module to be installed)
eval - evaluate the given code as (non-utf-8) Perl, basically the reverse of "-t dump"
yaml - YAML (avoid at all costs, requires the YAML module :)
string - do not attempt to decode te file data
none - nothing is read, creates an "undef" scalar - mainly useful with "-e"
-t toformat
Write the file in the given format to STDOUT.

"toformat" can be one of:

json, json-utf-8 - json, utf-8 encoded
json-pretty - as above, but pretty-printed
json-utf-16le, json-utf-16be - little endian/big endian utf-16
json-utf-32le, json-utf-32be - little endian/big endian utf-32
storable - a Storable frozen value in network format
storable-file - a Storable file in network format (Storable has two incompatible formats)
bencode - use Convert::Bencode, if available (used by torrent files, among others)
clzf - Compress::LZF format
yaml - YAML
dump - Data::Dump
dumper - Data::Dumper
string - writes the data out as if it were a string
none - nothing gets written, mainly useful together with "-e"
Note that Data::Dumper doesn't handle self-referential data structures correctly - use ``dump'' instead.
-e code
Evaluate perl code after reading the data and before writing it out again - can be used to filter, create or extract data. The data that has been written is in $_, and whatever is in there is written out afterwards.


   json_xs -t none <isitreally.json

``JSON Lint'' - tries to parse the file isitreally.json as JSON - if it is valid JSON, the command outputs nothing, otherwise it will print an error message and exit with non-zero exit status.

   <src.json json_xs >pretty.json

Prettify the JSON file src.json to dst.json.

   json_xs -f storable-file <file

Read the serialised Storable file file and print a human-readable JSON version of it to STDOUT.

   json_xs -f storable-file -t yaml <file

Same as above, but write YAML instead (not using JSON at all :)

   json_xs -f none -e '$_ = [1, 2, 3]'

Dump the perl array as UTF-8 encoded JSON text.

   <torrentfile json_xs -f bencode -e '$_ = join "\n", map @$_, @{$_->{"announce-list"}}' -t string

Print the tracker list inside a torrent file.

   lwp-request http://cpantesters.perl.org/show/JSON-XS.json | json_xs

Fetch the cpan-testers result summary "JSON::XS" and pretty-print it.  


Copyright (C) 2008 Marc Lehmann <json@schmorp.de>