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jsonrange

USAGE

jsonrange [OPTIONS] [DOT_PATH_EXPRESSION] 

SYSNOPSIS

jsonrange returns returns a range of values based on the JSON structure being read and options applied. Without options the JSON structure is read from standard input and writes a list of keys to standard out. Keys are either attribute names or for arrays the index position (counting form zero). If a DOT_PATH_EXPRESSION is included on the command line then that is used to generate the results. Using options to can choose to read the JSON data structure from a file, write the output to a file as well as display values instead of keys. a list of “keys” of an index or map in JSON.

Using options it can also return a list of values. The JSON object is read from standard in and the resulting list is normally written to standard out. There are options to read or write to files. Additional parameters are assumed to be a dot path notation select the parts of the JSON data structure you want from the range.

DOT_PATH_EXPRESSION is a dot path stale expression indicating what you want range over. E.g.

The path can be chained together

OPTIONS

	-d	set delimiter for range output
	-delimiter	set delimiter for range output
	-h	display help
	-i	read JSON from file
	-input	read JSON from file
	-l	display license
	-last	return the index of the last element in list (e.g. length - 1)
	-length	return the number of keys or values
	-limit	limit the number of items output
	-o	write to output file
	-output	write to output file
	-v	display version
	-values	return the values instead of the keys

EXAMPLES

Working with a map

    echo '{"name": "Doe, Jane", "email":"jane.doe@example.org", "age": 42}' \
       | jsonrange

This would yield

    name
    email
    age

Using the -values option on a map

    echo '{"name": "Doe, Jane", "email":"jane.doe@example.org", "age": 42}' \
      | jsonrange -values

This would yield

    "Doe, Jane"
    "jane.doe@example.org"
    42

Working with an array

    echo '["one", 2, {"label":"three","value":3}]' | jsonrange

would yield

    0
    1
    2

Using the -values option on the same array

    echo '["one", 2, {"label":"three","value":3}]' | jsonrange -values

would yield

    one
    2
    {"label":"three","value":3}

Checking the length of a map or array or number of keys in map

    echo '["one","two","three"]' | jsonrange -length

would yield

    3

Check for the index value of last element

    echo '["one","two","three"]' | jsonrange -last

would yield

    2

Limitting the number of items returned

    echo '[1,2,3,4,5]' | jsonrange -limit 2

would yield

    1
    2