Split up JSON data into multiple files based on shared characteristics.
npm install groupby-cli
Split up JSON data into multiple files based on shared characteristics. Groupby is a command-line utility but can also be used from node.js.
``shell`
groupby staff.json 'staff/{department}.json'
In the example above, the resulting output will one file for each department,
each file containing an array of staff member objects for that department.
`shell`
npm install groupby-cli -g
Groupby expects an input JSON file that contains an array of similarly-structured
objects, and will group those objects when they have matching values for whatever
keys you specify as placeholders in the output pattern.
For example, staff/{department}.json will group objects together into department
the same file if their key matches.
Grouping on multiple keys is supported too:
`shell`
groupby staff.json 'staff/{department}/{country}/{role}.json'
The only requirement for groups is that values can be turned into a string
(and thus into a filename to which we can write the resulting JSON.) Values
will be slugified for use in filenames
but will be left as-is in the JSON.
In some cases, your output pattern uniquely identifies each
individual object, e.g.
`shell`
groupby staff.json 'staff/{username}.json'
To save just the objects without wrapping each of them in an array, use the
--unique flag. In --unique mode, Groupby will throw an error if your
output pattern does unexpectedly lead to groups that contain more than one item.
`javascript
// basic usage
var groupby = require('groupby-cli');
var groups = groupby.group(list, facets);
// usage that is more advanced, and more
// similar to the command-line
var keyPattern = 'staff/{departments}';
var staffByDepartment = groupby.group(staff, keyPattern);
var sales = staffByDepartment['staff/sales'];
`
groupby.group takes an options object as a third argument:
* underscore to underscore the slugified keys
* false by defaulttrue
* when using the command-line interface, this is always set to
* catch
* (default) to throw an error when encountering an uncategorizable object (this happens when not all objects contain a value for the specified facets)true
* : don't throw such errors and just get rid of any uncategorizable objects"destination"
* : create a group with all uncategorizable objects at the specified key
Groupby comes with a permissive ISC license.
The countries.json` dataset included among the examples comes with an
Open Database License.
For the latest version, see @mledoze's countries repository
on GitHub.