What is json?
The 'json' npm package provides a simple command-line tool for working with JSON data. It allows users to easily manipulate JSON objects, extract specific fields, and format JSON data in a readable way.
What are json's main functionalities?
Extracting specific fields
This feature allows you to extract specific fields from a JSON file. In this example, it extracts the 'name' field from 'data.json'.
json -f data.json name
Pretty-printing JSON
This feature formats JSON data in a readable way with indentation. The '-i' flag is used to pretty-print the JSON content of 'data.json'.
json -i data.json
Updating JSON data
This feature allows you to update JSON data directly from the command line. The '-I' flag is used to modify the file in place, and the '-e' flag is used to execute the provided JavaScript expression to update the 'name' field.
json -I -f data.json -e 'this.name="newName"'
Other packages similar to json
jq
jq is a lightweight and flexible command-line JSON processor. It allows for complex filtering, transformation, and extraction of JSON data. Compared to 'json', jq offers more advanced querying capabilities and a more powerful syntax for manipulating JSON data.
jsonfile
jsonfile is a simple module for reading and writing JSON files. It provides a straightforward API for interacting with JSON files in a Node.js environment. While 'jsonfile' focuses on file operations, 'json' provides command-line utilities for JSON manipulation.
json2csv
json2csv is a tool for converting JSON data to CSV format. It is useful for exporting JSON data into a more tabular format that can be used in spreadsheets and databases. Unlike 'json', which focuses on JSON manipulation, json2csv specializes in data format conversion.
json
is a fast CLI tool for working with JSON. It is a single-file node.js
script with no external deps (other than
node.js itself). A quick taste:
$ echo '{"foo":"bar"}' | json
{
"foo": "bar"
}
$ echo '{"foo":"bar"}' | json foo
bar
$ echo '{"age":10}' | json -E 'this.age++'
{
"age": 11
}
$ echo '{"latency":32,"req":"POST /widgets"},
{"latency":10,"req":"GET /ping"}
' | json -gaC 'this.latency > 10' req
POST /widgets
Features:
- pretty-printing JSON
- natural syntax (like JS code) for extracting particular values
- get details on JSON syntax errors (handy for config files)
- filter input JSON (see
-E
and -C
options) - fast stream processing
- JSON validation
- in-place file editing
See http://trentm.com/json for full docs and examples as a man page.
Follow @trentmick
for updates to json.
Installation
-
Get node.
-
npm install -g json
Note: This used to be called 'jsontool' in the npm registry, but as of
version 8.0.0 it has taken over the 'json' name. See npm Package
Name below.
OR manually:
-
Get the 'json' script and put it on your PATH somewhere (it is a single file
with no external dependencies). For example:
cd ~/bin
curl -L https://github.com/trentm/json/raw/master/lib/json.js > json
chmod 755 json
You should now have "json" on your PATH:
$ json --version
json 9.0.0
WARNING for Ubuntu/Debian users: There is a current bug in Debian stable
such that "apt-get install nodejs" installed a nodejs
binary instead of a
node
binary. You'll either need to create a symlink for node
, change the
json
command's shebang line to "#!/usr/bin/env nodejs" or use
chrislea's PPA as
discussed on issue #56.
Test suite
make test
You can also limit (somewhat) which tests are run with the TEST_ONLY
envvar,
e.g.:
cd test && TEST_ONLY=executable nodeunit test.js
I test against node 0.4 (less so now), 0.6, 0.8, and 0.10.
License
MIT (see the fine LICENSE.txt file).
Module Usage
Since v1.3.1 you can use "json" as a node.js module:
var json = require('json');
However, so far the module API isn't that useful and the CLI is the primary
focus.
npm Package Name
Once upon a time, json
was a different thing (see zpoley's json-command
here), and this module was
called jsontool
in npm. As of version 8.0.0 of this module, npm install json
means this tool.
If you see documentation referring to jsontool
, it is most likely
referring to this module.
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